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THE MAGAZINE OF MR • AUTUMN 2009
No more hiding.
Visualize liver stiffness like never before with
the first commercially available MR Elastography
page 18
Find out what’s really on their minds –
MR in psychiatry
page 44
Raising the bar in pelvic imaging
page 11
The information contained in this document is current as of publication of the magazine.
TA B L E O F
GE Healthcare News: GE Expands
into Extremity-Specific MRI Systems
page 6
CONTENTS
Clinical Value: Changing Patient
Management With MR Elastography
page 18
Clinical Value: MRI Helps Save
a Doctor’s Life
page 24
Clinical Value
GE Healthcare News
Welcome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Ascites Imaging Made Easy at 3.0T . . . . . . . . . . . . . . . . . . . . . . 10
Calendar of Events . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Raising the Bar in Body Imaging With 32-Channel Array. . 11
GE Expands into Extremity-Specific MRI Systems,
Grows Product Line. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Contrast-Enhanced 3.0T MR Imaging of the Liver . . . . . . . . 16
MR Leadership Announcement . . . . . . . . . . . . . . . . . . . . . . . . . . 6
healthymagination MR Products Announced . . . . . . . . . . . . . 7
ISMRM Results in “Four Firsts” . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Changing Patient Management With MR Elastography . . . 18
MRI Helps Save a Doctor’s Life . . . . . . . . . . . . . . . . . . . . . . . . . . 24
3D MR Free-Breathing Coronary Artery Imaging Adds
Value for Assessing Congenital Heart Disease . . . . . . . . . . . 26
Renal Artery MRA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
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Publications Team:
GE Contributors:
Tom Verghese
MR Global GM & Chief Marketing
Officer
Jordanna Carstensen
Services Marketing
Communications Leader, Americas
Chris Fitzpatrick
MR Global Marketing Programs
Manager
Joanna Jobson
MR Global Marketing Program
Manager
Katherine Patterson
Global Marketing Communications
Manager, MR
Stuart Clarkson
3.0T MR Marketing Manager,
Americas
Tracey Fox
Regulatory Affairs Manager
Steve Lawson
Clinical Marketing Specialist, MR
Mary Beth Massat
Editorial Consultant
Jason Deeken
MR Global Marketing Programs
Manager
Maggie Fung
Applications Development
Manager, Cardiac MR
S. Gay Luebchow
Cardiovascular Imaging Specialist
Jenifer McGill
Editorial Consultant
Meg Weichelt
Senior Graphic Designer
2
SignaPULSE • Autumn 2009
Lloyd Estkowski
Advanced Program Marketing
Manager, Body MR
Vicki Hanson
1.5T MR Marketing Manager,
Americas
Katie McMillan
Applications Development
Manager, Neuro MR
The information contained in this document is current as of publication of the magazine.
TA B L E O F
Clinical Value: Game On: Radiologists
are Gearing up
page 36
Technical Innovation: Saving Future
Memories
page 60
CONTENTS
Beyond the Scan: Making a Difference
Through healthymagination
page 75
Technical Innovation
Inhance Inflow IR Allows Robust, Contrast-Free
Imaging of the Renal Arteries . . . . . . . . . . . . . . . . . . . . . . . . . . . 33
Game On: With the XXI Olympic/Paralympic Winter
Games Around the Corner, Radiologists are Gearing up . . 36
Easy Steps for Ankle Imaging . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
DWI Demonstrates Strong Clinical Utility for Bone
and Soft Tumor Diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Collaboration: The Science of Working Together . . . . . . . . . 56
Saving Future Memories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
Hold the Contrast, See the Flow:
3D NCE-MRA of the Peripheral Vasculature . . . . . . . . . . . . . . 64
The First Wide-Bore MR System From
GE Healthcare Is Here . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Unlocking the Mysteries of the Mind . . . . . . . . . . . . . . . . . . . . . 44
Special Considerations When Using Functional MRI
as a Presurgical Mapping Tool . . . . . . . . . . . . . . . . . . . . . . . . . . 47
Discovery MR750 3.0T Elevates Clinical Utility
of High-Resolution Imaging of the Cranial Nerves . . . . . . . 50
Easy-to-use MR Fusion Software Helps Raise
Diagnostic Confidence. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Beyond the Scan
Maintain High-Quality Imaging, Control Service Costs
With AssurePoint Services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
Turning up the Heat on Patient Safety,
Turning it Down to Prevent Burning. . . . . . . . . . . . . . . . . . . . . . 72
MR: Making a Difference
Through healthymagination . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Shoji Nakagami
MR Marketing Manager, Japan
Daniel J. (Joe) Schaefer
Principal Safety Engineer, MR
Vinod Palathinkara
Global Marketing Programs
Manager
Laurent Stefani
AW Product Manager, Europe
Barbara Pirgousis
MRI Sales Specialist,
Australia/New Zealand
Sabina Prato
MR Advanced Applications Specialist
Silvain Vernet
MR Marketing Communications
Specialist, Europe
Rebecca Zimmer
Legal Counsel
© 2009 General Electric Company, doing business as GE Healthcare. All rights reserved. The copyright,
trademarks, trade names and other intellectual property rights subsisting in or used in connection
with and related to this publication are, the property of GE Healthcare unless otherwise specified.
Reproduction in any form is forbidden without prior written permission from GE Healthcare.
LIMITATION OF LIABILITY: The information in this magazine is intended as a general presentation of
the content included herein. While every effort is made by the publishers and editorial board to see
that no inaccurate or misleading data, opinion or statements occur, GE cannot accept responsibility
for the completeness, currency or accuracy of the information supplied or for any opinion expressed.
Nothing in this magazine should be used to diagnose or treat any disease or condition. Readers are
advised to consult a healthcare professional with any questions. Products mentioned in the magazine
may be subject to government regulation and may not be available in all locations. Nothing in this
magazine constitutes an offer to sell any product or service.
A GE Healthcare MR publication • Autumn 2009
3
The information contained in this document is current as of publication of the magazine.
G E H E A LT H C A R E N E W S
WELCOME
Welcome
Quality counts. That’s the theme for the 2009 Radiological
Society of North America (RSNA) Annual Meeting. While
quality has always been at the forefront of all of our efforts
in healthcare, it hits home even harder for us this year. Never
before have we seen a more challenging environment in
healthcare – and never before have we been tasked to be
as proactive, as innovative, and smart about the decisions
we make.
I like a good challenge. Challenge brings innovation. It’s
not good enough to be complacent and satisfied with the
status quo when the environment is tough. The easy thing
to do in this environment would be to “cut things out” and
make compromises – compromises that affect your clinical
capability. We won’t do that.
Put simply, we’ve been inspired. Never before have we seen
such determination and collaboration from folks all around
the world – all working together to find a better way to bring
to light products that make sense. You’ve been telling us you
want simple solutions that make sense.
We were listening. And over the last 18 months, we in the
MR business at GE Healthcare have been busy.
What’s new? Just about everything in our entire portfolio. We
started showing the fruits of our labor at the 2008 ISMRM
Annual Meeting, where we introduced the Discovery™ MR750
3.0T. It’s an entirely new design that was developed with our
customers for sites that are looking to push the boundaries
of MR imaging but maintain simplicity and ease of use. We
then brought the same cutting-edge capabilities to the most
widely used field strength of 1.5T – the Discovery MR450.
Some have asked us why we didn’t put a 70-cm system
on our roster earlier. Well, there’s a method to our madness.
The meticulous innovations on the new Discovery enabled
us to move carefully and overcome the 40% loss of efficiency
that results in moving to 70 centimeters. The end result?
The Optima MR450w. The system that achieves this and
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SignaPULSE • Autumn 2009
has embarrassingly good image quality. It’s the difference
between a wide-bore system that’s done right vs. a wide-bore
system with compromise.
At this year’s RSNA, we’re going to continue to show you
even more new innovations – all of which underscore the
importance of how quality counts. They include MR-Touch
and we’re also going to be showcasing the ONI MSK Extreme
1.5T – the highest field strength extremity scanner, not to
mention new 32-channel coils for torso, brain, and cardiac
and extending our robust non-contrast enhanced applications
to the 3.0T line.
During 2009 we also launched leading applications like
IDEAL, Inhance, Cube and SWAN and at RSNA we will be
previewing applications that we will launch in 2010 to
continue to improve the performance of our HDxt and
Discovery platforms.
I’m not doing justice to these new innovations by simply
listing them. You truly have to see them to believe. And
there’s more to come. And more to come after that. I offer
you the personal invitation to stop by the MR booth at RSNA
or come to our headquarters in Wisconsin and see our
products in action. I have never been more confident than
right now regarding the performance and non-compromising
nature of our technology.
The climate is changing – but our promise to you will not.
Quality counts. We will make no compromises in our quest
to build solutions that meet the needs of you, our customers.
And we will continue to help you adapt to the challenges
facing the healthcare industry. Our promise is to give you
MR technology that’s done right.
James E. Davis
Vice President and General Manager,
Global MR Business, GE Healthcare
The information contained in this document is current as of publication of the magazine.
CALENDAR OF EVENTS
G E H E A LT H C A R E N E W S
GE looks forward to seeing you at the following events in 2010.
Date
Conference
Site
City/State
Country
Web Address
Jan. 16 – 17
Society of Breast Imaging
The Fairmont Dallas
Dallas, TX
USA
www.sbi-online.org
Jan. 21 – 24
Society for Cardiovascular
Magnetic Resonance (SCMR)
Sheraton Downtown
Phoenix
Phoenix, AZ
USA
www.scmr.org
Jan. 25 – 28
Arab Health
Dubai International
Exhibition Center
Dubai
United
Arab
Emirates
www.arabhealthonline.com
Feb. 14 – 19
Snowmass 2010: New
Advances in MR & CT
Snowmass
Conference Center
Snowmass Village, CO
USA
www.educationalsymposia.com
Feb. 15 – 19
Harvard Medical School MRI
2010: Clinical Updates and
Practical Applications
The Westin
Resort and Spa
Los Cabos
Mexico
http://cme.hms.harvard.edu/index.asp
Feb. 21 – 24
The Breast Course
Hilton Tapatio
Cliffs Resort
Scottsdale, AZ
USA
www.thebreastpractices.com
Feb. 24 – 26
American Society of
Functional Neuroradiology
(ASFNR)
Encore at Wynn
Las Vegas
Las Vegas, NV
USA
www.asfnr.org
March 4 – 8
European Congress
of Radiology 2010 (ECR)
Austria Center
Vienna
Vienna
Austria
www.myesr.org
March 9 – 13
American Academy of
Orthopaedic Surgeons (AAOS)
Morial Convention
Center
New Orleans, LA
USA
www.aaos.org
March 14 – 16
American College of
Cardiology (ACC) 59th Annual
Scientific Sessions
World Congress
Center
Atlanta, GA
USA
www.acc.org
April 8 – 11
The 69th Annual Meeting of
Japan Radiological Society
Pacifico Yokohama
Yokohama,
Kanagawa
Japan
www.secretariat.ne.jp/jrs69/
english/invitation_eng.html
April 12 – 14
27th Annual MRI of the
Head & Spine 2010: National
Symposium
Wynn Las Vegas
Las Vegas, NV
USA
www.educationalsymposia.com
April 12 – 16
27th Annual Magnetic
Resonance Imaging 2010:
National Symposium
Wynn Las Vegas
Las Vegas, NV
USA
www.educationalsymposia.com
April 13 – 17
Society of Pediatric
Radiology (SPR)
Boston Park Plaza
Hotel & Towers
Boston, MA
USA
www.pedrad.org
April 29 – May 2
40th São Paulo Radiological
Meeting – JPR 2010
Transamerica
Expo Center
São Paulo, SP
Brazil
Not available at time of printing
May 1 – 5
American Association
of Neurological Surgeons
Pennsylvania
Convention Center
Philadelphia, PA
USA
www.aans.org
May 1 – 7
International Society of
Magnetic Resonance in Medicine
(ISMRM) – 18th Scientific
Meeting and Exhibition
Stockholm
International Fairs
Stockholm
Sweden
www.ismrm.org
A GE Healthcare MR publication • Autumn 2009
5
The information contained in this document is current as of publication of the magazine.
G E H E A LT H C A R E N E W S
ANNOUNCEMENTS
GE Expands into Extremity-Specific MRI Systems,
Grows Product Line
Scanners designed for premium, patient-friendly extremity imaging
GE Healthcare purchased certain assets of ONI Medical System’s
unique specialty MRI technology platform, which expands
the company’s MRI capabilities and offers healthcare
professionals a broader range of patient-friendly MRI
offerings with uncompromised clinical performance.
Two new systems are now part of the GE MR portfolio.
The MSK Extreme 1.0T and the MSK Extreme 1.5T feature
a smaller footprint and quieter operation (relative to wholebody designs), premium image quality and an improved
patient experience. Both systems are designed specifically
to image the extremities – only the joint being imaged is
inside the scanner. The smaller footprint results in more
siting flexibility and the premium image quality provides
radiologists with clinical capabilities that are comparable,
and in some cases superior, to whole-body MR systems.
“One of the cornerstones of GE’s healthymagination vision
is to develop and invest in technologies that increase quality,
improve access, and decrease costs. In line with this vision, the
addition of ONI’s products enhances our magnetic resonance
business. It gives us an opportunity to explore technologies
that will increase access for claustrophobic patients, products
with a smaller footprint and premium image quality, and
specialty systems that provide advanced, cost-effective
MR imaging,” says Jim Davis, vice president and general
manager of GE Healthcare’s global MR business.
The current installed base of these two products is more than
175 units worldwide, including some of the top academic
hospitals. The systems have a combination of features –
high image quality, fast scan times, robust pulse sequences,
and a small footprint. Even patients with extreme cases
of claustrophobia are able to sit comfortably for their MRI
scan, with no compromises in image quality compared to
whole-body scanners. The systems can be placed alongside
whole-body MRI units in hospitals and imaging centers as
a market differentiator or a more optimal way to reduce
patient backlogs. „
MR Leadership Announcement
Tom Verghese, PhD, has recently joined the GE Healthcare team as the GM and chief marketing
officer for the MR business. Formerly the director for emerging markets for General Electric, Verghese
has an extensive track record in a variety of business leadership and global roles and brings deep
strategic and marketing knowledge to the MR business.
“We couldn’t be more thrilled to have Tom join the MR team here at GE Healthcare,” says Jim Davis,
vice president and general manager of the Global MR Business for GE Healthcare. “Tom’s experience
and passion are an excellent addition to the business and we are looking forward to his contribution.”
Verghese holds a PhD and BA in Chemical Engineering from the University of Cambridge, as well
as an Executive MBA from the Kellogg School of Management, Northwestern University. „
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
ANNOUNCEMENTS
G E H E A LT H C A R E N E W S
healthymagination MR Products Announced
GE’s healthymagination represents the company’s
commitment to deliver product and services that allow
physicians to deliver better care to more people at a lower
cost. Announced in spring of 2009, healthymagination has
been launched to address an industry challenged by rising
costs, inequality of access and persistent quality issues.
The aim of the initiative is to innovate smarter
processes and technologies that help physicians
and hospitals throughout the world provide
a higher level of healthcare to more people –
and save costs in the process.
While all GE Healthcare products and services
are in the spirit of healthymagination, only those
products that pass a rigorous third-party assessment
will carry the title of healthymagination verified.
Simply put, they must provide third-party evidence of
reducing cost, increasing access and heightening quality
for healthcare providers and patients.
GE is pleased to announce that two MR products have passed
the rigorous third-party assessment to be healthymagination
verified – MR-Touch (see page 18) and MR-guided Focused
Ultrasound (MRgFUS).
MRgFUS for uterine fibroids consists of a thermal ablation
device integrated with an MR imaging system, which allows
for the targeted destruction of fibroids. Uterine fibroids are
smooth muscle tissue growths of the uterus that affect at
least 25-35% of women over the age of 35. Of these, around
50% are considered clinically significant. Hysterectomy is
the most common treatment. It is estimated that uterine
fibroids account for 30-70% of all hysterectomies carried
out in the United States. However, hysterectomy is a highly
invasive procedure which entails significant adverse effects
and longer recovery times than alternative treatment options.
With MRgFUS, MR imaging defines the target and controls
and monitors the ablation, while a transducer controls
and delivers the focused ultrasound beam. A set of
MR images is produced which identifies a target
volume of tissue to be treated. Therapy planning
software then calculates the type and number
of sonications (pulses of ultrasound energy used
to agitate particles, resulting in chemical or
physical change) required to treat the affected area.
During the treatment, a small bean-shaped volume
of focused ultrasound energy is directed into the target for
approximately 15 seconds and heats the tissue to between
60 and 90°C to induce the thermal coagulation that produces
tissue necrosis. MR images continue to be taken throughout
the process to determine the correct position of the focal
spot and monitor temperature. Currently, US guidelines of
the procedure are limited to women who have completed
child bearing. Other countries, however, have less restrictions
upon its use with women who are looking to maintain fertility.
healthymagination is about making a difference in the health
and welfare of human beings everywhere. Please see page 75
to learn more about healthymagination. „
The ExAblate 2000
Currently, the only FDA-cleared system for
MRgFUS is the ExAblate 2000 from InSightec,
Ltd. To identify the treatment volume,
the ExAblate 2000 uses conventional
diagnostic MR images taken at the
beginning of treatment. The physician
delineates the fibroids and defines safe
treatment pass-zones that will avoid
energy passage through sensitive tissue.
The physician selects an applicationspecific treatment protocol that determines
the main attributes of the planned
treatment. The system then computes
a treatment plan, composed of 20 to 100
sonication points that cover the specified
target. During treatment, the system’s
robotic system positions the transducer
below the target point and delivers the
planned energy.
A key feature of ExAblate 2000 is its
ability to provide real-time monitoring
of energy deposition. During energy
delivery, ExAblate 2000 directs the MR
to continuously acquire thermal images
that include the point being treated and
the surrounding anatomy. These images,
once processed, provide the essential
feedback of where the energy is delivered
and the temperature reached. This
quantitative feedback allows the
physician to monitor and adjust
treatment parameters.
The workstation displays thermal images
and computes and displays the treated
regions. Spots are treated in sequence.
The process of adjusting parameters and
sonicating under real-time MR imaging
continues until the planned volume of
treatment is fully treated. Viewing images
of the region immediately following
treatment enables the physician to
evaluate the treatment outcome.
According to sources at InSightec, over
5,000 women have been treated with
ExAblate 2000 with close to 92%
experiencing symptom relief.
A GE Healthcare MR publication • Autumn 2009
7
The information contained in this document is current as of publication of the magazine.
G E H E A LT H C A R E N E W S
USER GROUP
ISMRM Results in “Four Firsts”
1
The International Society for Magnetic Resonance in
Medicine’s (ISMRM’s) annual convention resulted in
“four firsts” for GE Healthcare – further underscoring the
company’s leadership position in magnetic resonance (MR).
First-time validation of 3-D MRI technique for assessing growth plate
A team from the Hospital for Special Surgery (HSS) in New York and GE Healthcare developed technology
that sheds insight into the anatomical nature of bar (a bridge of bone). Dr. Matthew Koff from HSS
presented the findings at ISMRM. As lead author, his paper was titled, “Correlation of MRI and
Histological Examination of Physeal Bars in a Rabbit Model.”
To summarize, near the end of the long bones, there’s a region of growing tissue called the growth
plate or physis. It influences the length and shape of the bone as we develop from children into adults.
Health problems are all too common when conditions such as trauma affect the growth plate in
children. A bridge of bone, or bar, forms across an open growth plate. The presence of bar may
result in limb-length discrepancies or angular deformities later in life.
For the first time, this research project validated indirect measurement of physeal bar area from
three-dimensional magnetic resonance imaging (MRI) with direct histological measurements.
“Growth plate fractures frequently result in partial growth arrest and deformity especially around the
knee. This imaging technology helps quantify the size of growth arrests, and provides more accurate
information for clinical decision-making regarding growth preservation strategies, such as physeal
bar resection,” says HSS Chief of Pediatric Orthopaedic Surgery, Dr. Roger Widmann.
2
8
The research is a compelling example of collaboration between investigators in academia and industry.
This physeal segmentation technology is hoped to allow an orthopedic surgeon to appreciate the
location and extent of bar and possibly develop predictive models for the amount of bar. Perhaps
one day, a surgeon will use the technology integrated into a navigational system to plan the best
surgical approach that will minimize damage to normal physis during treatment.
First 1.5T human system, first subject – Gold Medal Award
GE Healthcare’s John Schenck, MD, PhD, was awarded the Gold Medal – the ISMRM’s most prestigious
award given annually to only one or two pioneering individuals in the field of MR. Dr. Schenck helped
develop the first 1.5T Human System and was the first subject more than 30 years ago.
SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
USER GROUP
G E H E A LT H C A R E N E W S
for GE Healthcare
First-place musculoskeletal poster, first author
At ISMRM, awards were given to the top three posters in 12 categories, and GE Healthcare’s Michael
Carl (first author) won first place for musculoskeletal. The company’s Albert Chen was co-author on
the second place poster for spectroscopy and hyperpolarization.
3
First-time for more than 100 first-authored presentations
For the first time, GE Healthcare offered more than 100 first-authored presentations – 110, to be
exact – in all three categories (e-posters, posters and talks) at ISMRM. Overall, the company continued
to lead all vendors with 273 presentations, an increase of 52% over 2008, including more than
170 different GE authors and collaboration with 100 sites globally.
In addition to leading the industry with the most research presented, the company took it one step
further by inducting the third annual “GE Healthcare Thought Leaders.” The 2009 inductees were
selected based on their contributions to the MR industry and forward thinking. The topics, while
not commercially available, could be reality in years to come.
Following is this year’s class, which presented cutting-edge MR topics. Please see page 56
for information about the topics.
• Michael Lustig, PhD, Stanford University
• Krishna Nayak, PhD, University of Southern California
• Takayuki Masui, MD, Seirei Hamamatsu General Hospital, Hamamatsu, Japan
• Jeff Duyn, PhD, National Institutes of Health and Pratik Mukherjee, MD, PhD, University of California,
San Francisco
• John Kurhanewicz, PhD, University of California, San Francisco
• Martin Graves, MSc, Cambridge University Hospitals, Cambridge, UK
4
• Jingfei Ma, PhD, University of Texas MD, Anderson Cancer Center
• (Alexander) Sandy Dick, MD, Sunnybrook Health Sciences Centre, Toronto, Ontario
• Garry Gold, MD, Stanford University „
A GE Healthcare MR publication • Autumn 2009
9
The information contained in this document is current as of publication of the magazine.
BODY IMAGING
Ascites Imaging
Made Easy at 3.0T
CLINICAL VALUE
Dr. Lawrence N.
Tanenbaum, FACR
By Lawrence Tanenbaum, MD, FACR, Director of MRI and CT,
Mount Sinai School of Medicine
Lawrence N. Tanenbaum, MD, FACR, is Director of
MRI, CT and Outpatient/Advanced Development,
Mount Sinai School of Medicine (MSSM). The
school opened its doors in the fall of 1968 and
has since become one of the world’s foremost
centers for medical and scientific training.
Located in Manhattan, MSSM works in tandem
with The Mount Sinai Hospital to facilitate
the rapid transfer of research developments
to patient care and clinical insights back
to the laboratory for further investigation.
Historically, abdominal imaging at 3.0T has been a challenge due to a number
of issues including RF inhomogeneity/dielectric/wavelength effects (RFI) and
chemical shift. As a result, many abdominal magnetic resonance imaging
(MRI) studies that might have benefitted from the signal-to-noise ratio (SNR)
and resolution of 3.0T were instead triaged away to 1.5T. RFI issues were
particularly problematic when imaging patients with ascites (excess fluid
in the space between the tissue lining the peritoneal cavity).
With the introduction of the Discovery MR750 3.0T and a new 16-rung quadrature
birdcage RF coil, GE Healthcare has helped resolve these limitations of abdominal
MR imaging. The RF body coil design is based on a 16-rung quadrature hybrid
birdcage that is driven at four different ports with fixed delays between each
port, which virtually eliminates RF shading with improved resilience to different
body sizes and shapes.
The imaging results are consistent and impressive. In Figure 1, T2 weighted
imaging of the hips and abdomen are demonstrated.
The abdominal case shows coronal and axial images of a patient with ascites
due to cirrhosis. The hips are typically one of the most challenging exams to
perform at 3.0T as the structures of interest are superficial within the body.
Note the degenerative disease, and the impressive absence of shading
and the excellent image uniformity on both studies.
At 3.0T, we can now take advantage of the higher SNR and improved image
quality, which together help raise diagnostic confidence. „
Images courtesy of Mt. Sinai School of Medicine.
Discovery MR750 3.0T
1a
1b
Figures 1a and 1b. 3.0T body images of an abdominal case demonstrates spectacular images
of ascites (Figure 1a) and the hips (Figure 1b).
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The information contained in this document is current as of publication of the magazine.
Raising the Bar
in Body Imaging
With 32-Channel Array
In recent years, significant developments to magnetic
resonance (MR) scanner hardware and software emerged
such as boosting signal-to-noise ratio (SNR) with advanced
optical receiver technology, more powerful whole-body
gradients, robust fat-water separation techniques, and
increasing the number of RF (radio frequency) channels.
Yet to a certain degree coil technology has lagged. This
has changed with the introduction of the Discovery™
platform from GE Healthcare. With 32 receiver channels
and scalable reconstruction architecture, this new platform
raises the bar for the development of new phased
array coils capable of acquiring and reconstructing
data simultaneously from 32 elements, particularly
for body imaging.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
P E LV I C I M A G I N G
The Centre for Magnetic Resonance Investigations,
University of Hull (United Kingdom) was one of the first
facilities in the world to combine the Discovery MR750
platform with a 32-channel torso coil. According to
Professor Lindsay Turnbull, MD, scientific director, “We were
very excited to see how far we could push our Discovery MR750
body protocols with a 32-channel coil and, equally, understand
how this would impact our diagnostic confidence.”
Initial experience with the Discovery MR750 and 32-channel
torso coil was during a factory visit prior to procurement.
Martin Pickles, PhD, research radiographer, explains, “It was
clear from our visit that the 32-channel torso coil provides
greater SNR, and thereby the opportunity for greater spatial
resolution, but also adds versatility with a large Z-axis coverage
and the ability to run the coil in many configurations, such
as lower, upper, and full.”
For Professor Turnbull, while coil versatility remains important,
the more significant clinical advantage is the additional SNR.
Using the higher SNR to generate better image quality
also opens up possibilities for parallel imaging techniques
by enabling scan speeds at 12 times or greater acceleration
factors. The result is shorter total exam times and more
definitive patient reports.
Increasing spatial resolution or volumetric coverage can
lead to full or tighter field-of-views (FOVs), depending on
the application and prescription. A larger FOV translates to
fewer scans and patient repositioning, an easier scanning
process, and more consistent scans.
By combining the Discovery MR750’s reconstruction and
receiver architecture power with the high-density, 32-channel
torso coil, the additional SNR enables higher quality imaging
without the burden of additional time or challenge of a long
breath-hold for both routine and advanced abdominal and
pelvic imaging. „
Case 1. Prostate
Diagnosis:
A 49-year-old patient had rising PSA but a negative biopsy.
The patient was referred to exclude prostate cancer or to
provide target for biopsy.
Right anterior prostate tumor stage T2aNo.
The MR scan revealed a moderately enlarged prostate and
benign prostatic hyperplasia was noted throughout the
central gland. Hyperintense bilateral peripheral zones were
observed on T2w images. Water-only LAVA-Flex, multiphase,
3D volumes revealed a 19 millimeter oval shaped lesion with
an associated Type III signal intensity curve. This lesion was
located on the right anterior aspect of the prostate at the
junction of the middle and lower third of the gland. There
was no evidence of extracapsular extension, pelvic
lymphadenopathy, or focal boney abnormality.
Figure 1a. Positive enhance integral color map
overlaid onto axial high resolution T2w images.
12
“In this patient cohort, increasing spatial resolution by utilizing
the extra SNR significantly raises our diagnostic confidence.”
SignaPULSE • Autumn 2009
Management:
A repeat biopsy of the right anterior prostate revealed
carcinoma Gleason grade 8.
Protocol:
High spatial resolution axial T2w: FRFSE-XL, TR 5860,
TE 106.7/Ef, 31.2 kHz, ETL 17, FOV 20x20 cm, 3/0mm,
384x256, 4 NEX
LAVA-Flex multiphase volumes: 3D LAVA-Flex, flip 12o, TR 4.3,
TE 1.3 and 2.6, 166.7 kHz, FOV 34x30.6 cm,
4/0 mm, 24 locs, 320x192, 0.75 NEX
Figure 1b. Axial spatial high resolution T2w
images demonstrate hypointense T2w signal
intensity lesion.
Figure 1c. Coronal high spatial resolution T2w
image again reveals hypointense T2w signal
intensity lesion.
The information contained in this document is current as of publication of the magazine.
P E LV I C I M A G I N G
CLINICAL VALUE
Case 2. Ovarian mass
Diagnosis:
An 86-year-old patient presented with lower abdominal
pain and swelling. An ultrasound scan revealed a solid mass
originating from the right ovary. The patient was referred for
MRI to aid in the management decision – either debulking
surgery or non-surgical oncologic treatment.
Right ovarian malignancy with small peritoneal seedings
and omental thickening. The lesion within the endometrium
may represent metastatic spread or a synchronous
malignancy FIGO 3c.
The MR scan revealed an irregularly shaped 6.6 centimeter
right adnexal mass with solid and cystic components. The
lesion was predominately of low signal intensity with a number
of tiny cysts present. The lesion appeared unencapsulated
throughout and demonstrated a central vascular pedicle. A
hypointense fibroid arising from the anterior aspect of the
uterus was also noted, while a mixed signal intensity mass
expanded the endometrium. A number of tiny peritoneal
projections were observed, which were suspicious of small
deposits, and there was diffuse thickening of the omentum.
As a result of the MR exam, two treatment options were
offered - surgical debulking or chemotherapy/radiotherapy.
The patient elected to undergo surgery.
Management:
Protocol:
Sagittal T2w: FRFSE-XL, TR 2940, TE 112.0/Ef, 41.7 kHz,
ETL 19, FOV 24x24 cm, 4/1 mm, 512x320, 3 NEX
Axial T2w: FRFSE-XL, TR 3240, TE 115.0/Ef, 41.7 kHz, ETL 19,
FOV 24x24 cm, 4/1 mm, 512x448, 2 NEX
Axial DWI: SE/EPI, TR 3500, TE 67.5/FE, 250 kHz, FOV 38x38 cm,
6/0.6 mm, 160x160, 9 NEX, b=0 & 1200 s/mm2 applied in all
three orthogonal planes
Oblique T2w: FRFSE-XL, TR 3480, TE 110.9/Ef, 41.7 kHz,
ETL 19, FOV 24x24 cm, 3/0.3 mm, 512x320, 2 NEX
2a
2b
2c
Figures 2a, 2b, and 2c. Sagittal T2w images reveal a large irregular shaped solid right adnexal mass with free intraperitoneal fluid present.
Figure 2a. Magnified to demonstrate the tiny peritoneal projections and the expansion of the endometrium.
2d
2e
2f
2
Figures 2d and 2e. Axial T2w image, and Figure 2e. Axial b=1200s/mm diffusion image, both
reveal solid components of the ovarian mass and endometrial expansion.
Figure 2f. Oblique T2w perpendicular to long
axis of uterus, demonstrates the relationship
between the fibroid, endometrial expansion,
and ovarian mass.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
P E LV I C I M A G I N G
Case 3. Ovarian mass
Diagnosis:
A 30-year-old patient presented with a four-week history of
lower abdominal pain and swelling. An ultrasound scan revealed
a complex cyst with some irregular solid components
originating from the right ovary. The patient was referred
for MRI to aid in the management decision – either debulking
surgery or non-surgical oncologic treatment.
Malignancy arising from right ovary FIGO 1.
The MR scan revealed a 15x11x10 centimeter mass with
solid and cystic components. The solid components
demonstrated mixed signal intensities interspersed with
small cystic areas, some of which contained hemorrhagic
contents. Although some thickening of the omentum was
noted there was no obvious change in signal intensity.
Sagittal T2w: FRFSE-XL, TR 2940, TE 112.0/Ef, 41.7 kHz,
ETL 19, FOV 24x24 cm, 4/1 mm, 512x320, 3 NEX
Management:
Left salpingo-oophorectomy and omentectomy, pathology
immature teratoma FIGO 1a.
Protocol:
Axial T2w: FRFSE-XL, TR 3240, TE 115.0/Ef, 41.7 kHz, ETL 19,
FOV 24x24 cm, 4/1 mm, 512x448, 2 NEX
Axial DWI: SE/EPI, TR 3500, TE 67.5/FE, 250 kHz, FOV 38x38 cm,
6/0.6 mm, 160x160, 9 NEX, b=0 & 1200 s/mm2 applied in all
three orthogonal planes
3D T1w: 3D FSPGR, 15o Flip, TR 12, TE 2.11/Fr, 31.2 kHz,
FOV 30x22.5 cm, 1.4/-0.7 mm, 260 locs, 320x224, 1 NEX
3a
3b
Figures 3a and 3b. T2w images acquired in the sagittal and axial plane reveal a large pelvic mass
of mixed cystic and solid components.
3d
3e
3c
Figure 3c. b = 1200 s/mm2 diffusion image
reveals solid component.
3f
Figures 3d, 3e, and 3f. Reformatted axial, sagittal, and coronal images from a T1w 3D FSPGR fat saturated post contrast data set again demonstrate
the mixed nature of the pelvic mass.
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
P E LV I C I M A G I N G
CLINICAL VALUE
Case 4. Abdominal metastases
A 32-year-old patient with past history of right salpingo-oophorectomy in 2006
for granulosa cell tumor. A routine surveillance ultrasound scan revealed advanced
metastatic disease. The patient was referred to MRI for staging.
In addition to the disease present prior to consideration for debulking surgery, MRI
revealed extensive peritoneal involvement over the liver with additional disease
extending into the porta-hepatis. A well-defined 2.6 centimeter mass was noted
in segment 7 of the liver. This lesion demonstrated hyperintense signal intensity on
diffusion imaging but was unchanged since the patient’s initial scan and, therefore,
likely represented focal nodular hyperplasia. Omental thickening was noted
along with a pleural effusion.
Figure 4a. Respiratory trigger axial T2w fat
suppressed image demonstrates peritoneal disease
and focal nodular hyperplasia within segment 7.
Diagnosis:
FIGO 4.
Management:
The patient was referred to an oncologist for chemotherapy.
Protocol:
Respiratory triggered axial T2w: FRFSE-XL, TR 10435, TE 92.6/Ef, 31.2 kHz, ETL 12,
FOV 36x28.8 cm, 5/0 mm, 352x224, 2 NEX
Axial DWI: SE/EPI, TR 2000, TE 59.4/FE, 250 kHz, FOV 40x32 cm, 8/2 mm, 80x128,
4 NEX, b=0 & 1200s/mm2 applied in SI direction only
Figure 4b. Axial b 1200s/mm2 diffusion image
again reveals peritoneal disease and focal nodular
hyperplasia within segment 7. Note increased
contrast-to-noise ratio of lesions (arrows) in diffusion
image compared to T2w fat saturated image.
Case 5. Ovarian cysts
A 77-year-old patient on hemodialysis due to chronic kidney disease was
referred for ultrasound due to elevated liver enzymes. An incidental finding of
a left adnexal was reported; mass was believed to contain thick walled and solid
elements. The patient was referred for MRI to exclude malignancy.
Both ovaries were enlarged, the left greater than the right, and composed of multiple
cysts of varying sizes demonstrating hyperintense T2w signal. The intervening
septations were smooth and thin with no evidence of endocystic projections and
were of hypointense T2w signal. The capsule of both lesions appeared intact.
Diagnosis:
Figure 5a. Sagittal T2w image through left ovary
Probable bilateral ovarian cystadenofibromas.
Management:
A repeat examination at three months showed no change in appearance.
CA 125 was normal; the patient was discharged from follow up.
Protocol:
Sagittal T2w: FRFSE-XL, TR 2940, TE 112.0/Ef, 41.7 kHz, ETL 19, FOV 24x24 cm,
4/1mm, 512x320, 3 NEX
Oblique T2w: FRFSE-XL, TR 3480, TE 110.9/Ef, 41.7 kHz, ETL 19, FOV 24x24 cm,
3/0.3 mm, 512x320, 2 NEX
Figure 5b. Oblique T2w image through left ovary.
Both images reveal the internal architecture of the
multicystic ovary. Note, the patient had left
hip prosthesis.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
LIVER IMAGING
Contrast-Enhanced
3.0T MR Imaging of the Liver
By Tonsok Kim, MD, Assistant Professor, Department of Radiology, Osaka University Medical School of Medicine
A fat suppressed, T1-weighted 3D gradient echo (GRE)
sequence, such as LAVA-Flex (GE Healthcare), is used
for contrast-enhanced imaging. LAVA-Flex supplies high
speed and high resolution T1-weighted 3D GRE imaging
with a high signal-to-noise ratio (SNR) and high quality fat
suppression. Using a 3.0T MR system is advantageous for
contrast-enhanced imaging due to a higher SNR than 1.5T,
which enables faster scanning by using a larger reduction
factor for parallel imaging. Our protocol using GE Signa
HDxt 3.0T for contrast-enhanced imaging of the liver
is introduced.
At Osaka University, we conduct all contrast-enhanced
imaging of the liver on a GE Signa HDxt 3.0T MR system.
Following our protocol, we obtain dual-echo (in-phase
and out-of-phase) and fat suppressed T1-weighted
images before contrast enhancement. LAVA-Flex allows
us to simultaneously obtain water, fat, in-phase, and
out-of-phase T1-weighted 3D GRE images. With LAVA-Flex,
the fat suppressed T1-weighted images are extremely
good quality (Figure 1).
After administration of a liver-specific contrast agent, we
perform the LAVA-Flex sequence for dynamic multiphasic
16
SignaPULSE • Autumn 2009
(arterial, portal venous, and late phase) and hepatocyte
phase imaging in the axial plane (Figure 2). Arterial phase
imaging is performed just after confirming arrival of
contrast material at abdominal aorta by using the MR
SmartPrep bolus tracking program from GE Healthcare;
portal venous, late phase, and hepatocyte phase imagings
are performed one, three, and 20 min after the injection,
respectively. In the hepatocyte phase, coronal and sagittal
images are also obtained with LAVA-XV using ARC, a parallel
imaging technique that enables faster imaging in the coronal
and sagittal planes without misregistration artifact and with
a larger reduction factor than LAVA-Flex (Figure 2).
Use of a contrast agent does not affect image contrast
on T2-weighted images, therefore, these are obtained
using SSFSE (single shot fast spin echo) and respiratory
triggered fat suppressed FSE between late phase imaging
and hepatocyte phase imaging to shorten the examination
time. However, because contrast excreted in the bile causes
T2-shortening of the bile and deteriorates the depiction of
bile ducts using MRCP, this sequence should be obtained
before injecting the contrast agent. „
The information contained in this document is current as of publication of the magazine.
LIVER IMAGING
CLINICAL VALUE
Dr. Tonsok Kim
Figure 1a. Water
Tonsok Kim, MD, is associate professor of
Radiology and chief, Division of Abdominal
Radiology, at Osaka University Hospital. Dr. Kim
has gained much experience using 3.0T MRI
for abdominal imaging in clinical and research
studies since 2005, and he has completed several
comparison studies of 1.5T and 3.0T MR.
Figure 1b. Fat
About the institute
The Osaka University Hospital, established in
1931, is a national university hospital in the 2nd
largest prefecture in Japan. The hospital has
1,076 inpatient beds and serves approximately
2,440 outpatients each day. Osaka University
Hospital has used GE Healthcare MR scanners
since 1993 and currently operates a Signa HDxt
3.0T and Signa EXCITE HD 1.5T.
Figure 1c. In-phase
Figure 1d. Out-of-phase
Figures 1a to 1d. Images obtained with LAVA-Flex on a patient with early HCC confirmed
by histopathology (arrow), demonstrating intratumoral fat and hemorrhage. High signal
intensity of the lesion on the water image indicates intratumoral hemorrhage, while high
signal intensity on the fat image indicates intratumoral fat. Signal intensity loss on the
out-of-phase image compared to the in-phase image also suggests intratumoral fat.
Figures 2a to 2f. A patient case with chronic hepatitis
type B after surgery for rectal cancer. Arterial phase
image shows a hyperenhancing lesion (arrow) in the
anterior segment of the liver. Portal venous phase
image shows a lesion of hypoattenuation, but the
lesion is more prominent on the hepatocyte phase
image. The hypervascular lesion can be diagnosed
as HCC rather than metastasis from rectal cancer.
Histology confirmed the lesion was early HCC
after hepatic resection.
Figure 2a. Pre-contrast
LAVA-Flex axial image
Figure 2b. Arterial LAVA-Flex
axial image
Figure 2c. Portal venous
LAVA-Flex axial image
Figure 2f. Hepatocyte phase
fat suppressed LAVA-XV
coronal image
Figure 2d. Late phase
LAVA-Flex axial image
Figure 2e. Hepatocyte phase
LAVA-Flex axial image
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
LIVER IMAGING
Changing Patient Management
With MR Elastography
Chronic liver disease is a major problem worldwide and causes
tens of thousands of deaths each year in the United States.
An important diagnostic task in assessing patients with
suspected liver disease is to detect the presence of hepatic
fibrosis, which can often be treated if diagnosed early enough
before it progresses to irreversible cirrhosis. The current
practice for diagnosing liver fibrosis is needle biopsy. Liver
biopsy is, however, relatively expensive compared to
magnetic resonance imaging (MRI).1
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SignaPULSE • Autumn 2009
Hepatic fibrosis is known to increase the stiffness of the liver
tissue. Richard Ehman, MD, and colleagues at Mayo Clinic
(Rochester, MN), have developed a technique for noninvasively
measuring liver tissue stiffness – Magnetic Resonance
Elastography (MRE). This technology, licensed by Mayo
Clinic, is now being introduced by GE Healthcare. The
first commercial MRE application, called MR-Touch, is
innovative imaging technology that is available on
the Optima™ MR450w 1.5T system.
The information contained in this document is current as of publication of the magazine.
LIVER IMAGING
CLINICAL VALUE
Dr. Richard L. Ehman
MR-Touch employs low frequency sound waves in combination with MRI to probe
tissue stiffness. There are three steps to the process: generating acoustic waves
within the tissue of interest; imaging the micron level displacements of the tissue
that result from wave propagation using a special MRI technique with oscillating
motion-sensitizing gradients; and generating maps of the tissue stiffness, known as
“elastograms,” using a mathematical technique developed by Mayo Clinic physicians
and researchers.
MRE of the liver can be accomplished in an acquisition that lasts only 15 seconds
and is easily added to a standard MRI examination of the abdomen. A simple,
drumlike acoustic driver is placed in contact with the body. A flexible tube is
connected to a driver device outside the scan room that generates low-frequency
sound waves in the range of 40 to 90 Hz. The vibration should not cause
discomfort and has an amplitude that is typically less than 0.1 mm, which
falls well within established safety limits for vibration exposure.2
In a 2007 publication, the Mayo Clinic team reported hepatic fibrosis could be
detected with high sensitivity and specificity using the information provided by
MRE.3 The team’s findings indicate that MR elastography has a promising ability
to help discriminate between tissue stiffness consistent with mild, moderate,
and severe fibrosis.
Other research groups have reported similar results.4 These studies have also
compared the performance of MRE to a method for ultrasound-based measurement
of liver stiffness, called transient elastography.5 MRE had a higher rate of technical
success compared with ultrasound-based elastography and higher sensitivity and
specificity for identifying variations in tissue stiffness consistent with early stages
of hepatic fibrosis.4 Unlike ultrasound-based elastography, MRE can be performed
successfully in overweight patients and it depicts stiffness in a cross-sectional
image of the liver, so it is less likely to be affected by sampling error.6
Richard Ehman, MD, is professor of radiology at
the Mayo Clinic and serves as a member of the
Mayo Clinic Board of Governors.
He divides his time between clinical practice,
education, and research. His main clinical activity
is Magnetic Resonance Imaging. His research
program is focused on developing new imaging
technologies. Dr. Ehman has been Principal
Investigator of several NIH grants, holds more
than 30 US and foreign patents for his inventions,
and has authored more than 200 publications in
the scientific literature. He was awarded the Gold
Medal of the International Society for Magnetic
Resonance in Medicine in 1995 for his research
contributions, an honorary Doctor of Science
Degree by the University of Saskatchewan in
2000, and the Outstanding Researcher Award
of the Radiological Society of North America
in 2006.
Dr. Ehman has served as Chair of the Radiology
and Nuclear Medicine Study Section of the NIH,
and is currently a member of the Advisory
Council of the National Institute of Biomedical
Imaging and Bioengineering of the NIH. He is
an Associate Editor of Magnetic Resonance in
Medicine, and a member of the editorial boards
of several other journals. He served as President
of the International Society for Magnetic
Resonance in Medicine in 2002-2003.
Figure 1. Elastogram on volunteer patient is shown (right) and corresponding anatomic image
(left). In the elastogram, relative stiffness is shown on a color scale, ranging from softest (purple) to
hardest (red). For reference, a dashed outline has been superimposed on the elastogram to indicate
the approximate location of the liver. Note that the stiffness of normal liver tissue is very low and
similar to that of adipose tissue. The spleen is usually considerably stiffer than other tissues, as
shown by the corresponding red areas.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
LIVER IMAGING
Dr. Jayant A. Talwalkar
Jayant A. Talwalkar, MD, M.P.H., is associate
professor of Medicine, Miles and Shirley Fiterman
Center for Digestive Diseases, Center for
Advanced Imaging Research, Mayo Clinic in
Rochester, MN. Dr. Talwalkar received his MD
from the University of Illinois in 1993 and
completed residency training in Internal Medicine
at the Mayo Clinic in 1996, fellowship training in
Gastroenterology at the Brigham and Women’s
Hospital in 1999, and advanced training in
Hepatology and Liver Transplantation at the
Mayo Clinic in 2000. He joined the Mayo Clinic
staff in 2000. He is a member of editorial boards
for Gastroenterology, Hepatology, and Liver
Transplantation, and is currently Chair of the
Practice Guidelines Committee for the American
Association for the Study of Liver Diseases.
Dr. Talwalkar is also the Principal Investigator
of several NIH grants related to epidemiologic
and imaging aspects of acute and chronic
liver disease.
Figure 2. A 61-year-old with elevated serum liver tests and nonalcoholic fatty liver disease.
In this case of advanced liver fibrosis, the elastogram shows that the liver is much stiffer than
subcutaneous tissues and overall stiffness of the liver. The heterogeneity of the stiffness of the
liver is also increased (compared to volunteer in Figure 1).
References:
Many conditions can result in progressive hepatic fibrosis. Globally, one of the
most important causes of liver disease is chronic hepatitis C infection, which is
estimated to affect as many as 170 million people worldwide. While the condition
has minimal effects on most individuals, a subset (approximately 25%) develop
hepatic fibrosis. MRE has a role in identifying patients with diseases associated
with liver stiffness, as they may benefit from antiviral therapy.
1. Taouli B, Ehman RL, Reeder SB. Advanced MRI Methods for
Assessment of Chronic Liver Disease. AJR 2009;193:14-27.
2. Ehman EC, Rossman PJ, Kruse SA, et al. Vibration safety
limits for magnetic resonance elastrography. Phys Med Biol
2008;53(4):925-935.
3. Yin M, Talwalkar JA, Glaser KJ, et al. Assessment of hepatic
fibrosis with magnetic resonance elastography. Clin
Gastroenterol Hepatol 2007;5(10):1207-1213.
4. Huwart L, Sempoux C, Vicaut E, et al. Magnetic resonance
elastography for the noninvasive staging of liver fibrosis.
Gastroenterology. 2008 Jul;135(1):32-40
5. Castera L, Vergniol J, Foucher J, et al. Prospective comparison
of transient elastography, FibroTest, APRI, and liver biopsy
for the assessment of fibrosis in chronic hepatitis C.
Gastroenterology 2005; 128:343–350
6. Talwalkar JA. Elastography for detecting hepatic fibrosis: options
and considerations. Gastroenterology 2008; 135:299–302
7. Ehman RL. Science to Practice: MR Elastography of
steatohepatitis in fatty liver disease. Radiology 2009; 253: 1-3.
Figure 3. A 61-year-old with hepatitis C, cirrhosis, and hepatocellular carcinoma. The oval outline in
the anatomic image (left) shows the location of the hepatocellular carcinoma. The elastogram (right)
shows a corresponding area of high stiffness in the right lobe of the liver (red arrow), as well as an area
of very high stiffness in the left lobe of the liver (green arrow) that is consistent with advanced fibrosis.
A rising problem in developed countries is fatty liver disease, linked to obesity
and Type 2 diabetes, now affecting as much as one-third of the US population.7
While fatty liver disease has a benign course in many patients, a subset of people
develop steatohepatitis which can lead to progressive liver fibrosis and end stage
liver failure.
Researchers are exploring many other applications of MRE, including the potential
applications of this new imaging modality for evaluating the brain, heart, breast,
and musculoskeletal system.
Conclusion
MRE offers a new type of contrast in MRI, depicting the mechanical properties of
tissues. Due to the very short acquisition time, MRE can be included in standard
abdominal MRI protocols with minimal impact on exam time. „
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
LIVER IMAGING
CLINICAL VALUE
The Picture That Paints a Thousand
Words But Left a Patient Speechless
Up until 1998, life had its normal ups and downs for Deb Sobel,
who spoke often with her sister, Sarah Jane Kiley, via telephone.
They talked about everything from family and politics to
business and real estate. However, that was the year their
lives – and their conversations – would change forever.
Sarah was diagnosed via a biopsy with Primary Biliary
Cirrhosis (PBC), a rare autoimmune liver disease. Three
months after Sarah’s diagnosis, Deb
also had a biopsy and was diagnosed
with the same disease.
Deciding to seek a second opinion,
Deb and Sarah sought out Dr. Marshall
Kaplan at New England Medical Center
in Boston. The doctor confirmed the
sisters’ diagnoses, but he also did
something that no other doctor had
done: He encouraged them to be
patient advocates for the rare,
little-known disease.
Advocating for change
Sarah needed no further encouragement,
becoming very involved in the PBC support
network. She also became a strong
advocate for the PBCers organization
and the American Liver Foundation,
helping hundreds to find the healthcare
she so strongly believed they deserved.
a bacteria, and the transplant was not successful. While
the chances of survival are slim when PBC and infection
“overlap,” doctors were determined to perform a second
transplant. It was unsuccessful, and on June 29, 2006,
Sarah lost her battle with PBC at only 47 years of age.
Before Sarah died, Deb promised that her sister’s story
would help others. “Sarah was a huge patient advocate up
until her last breath,” remembers Deb.
“She still holds the torch. Sarah is not
able to communicate anymore, so I
am continuing her work and giving
her a voice.”
Hope on the horizon
Before Sarah Jane Kiley lost her battle with PBC,
she encouraged people to take responsibility for
their own health.
While watching CNN one day, Deb
saw a story about Mayo Clinic trials
of magnetic resonance elastography
(MRE) – a technology much like a
magnetic resonance imaging (MRI)
scan that uses a drum over the area
to be examined. The drum generates
sound waves that move through stiff
and supple tissue at different rates.
A computer analyzes the difference,
showing what’s healthy and what’s
not on a color scale.
Deb decided to fight for the opportunity
to access MRE. After speaking with
Dr. Jayant Talwalkar at the Mayo Clinic
“Sarah ran with it and became a fulland telling him about her sister Sarah,
fledged advocate for helping others
Dr. Talwalkar invited Deb to come in
with the disease,” explains Deb. “She
for an MRE. He even wrote letters to
treated each person she encountered
MRE revealed the extent and distribution
her insurance company to get partial
of fibrosis in Deb Sobel’s liver.
as family.”
coverage for the test, as it was still
After eight years of campaigning for PBC patient rights, Sarah’s
not FDA approved. In 2007, Deb had the MRE and saw the
condition had become so advanced that she underwent a
condition of her liver for the first time in the almost 10 years
liver transplant at the Cleveland Clinic in 2006. Unfortunately, she had been battling the disease.
Sarah developed an infection called pseudomonas,
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
LIVER IMAGING
Getting the whole picture
“Seeing my liver and the state of the disease for the first
time was a very powerful, emotional moment – it left me
speechless,” recalls Deb. “MRE painted a true picture of the
PBC progression. I used to be mad at my liver, but then I felt
bad for it and decided to protect and take care of it as much
as possible.”
While PBC can not be reversed, Deb feels strongly that MRE
will help her manage the disease and she is thankful that
MRE enabled her doctors to pinpoint the true state of the
PBC – as biopsies, she says, can be hit or miss. Knowing
exactly what is going on with her body is empowering.
“There are 100,000 women in the United States diagnosed
with PBC who could benefit greatly from the MRE technology.
It might not have saved Sarah’s life, but it could have helped,”
maintains Deb. “I want to carry on the advocacy started by
my sister to help women get this test.”
Deb’s passion is further fueled by Sarah’s two daughters
who could carry a hereditary component (the disease has
a 95% female hereditary component). She would like to
ensure that her nieces can have the test to track any
possibility of the disease and if necessary, begin a
management plan.
Sarah and Deb’s efforts will be rewarded soon. As mentioned
on the previous pages, GE Healthcare is collaborating with
the Mayo Clinic to be the first to bring MRE to hospitals and
clinics, commercially introduced as MR-Touch.
“I think it’s phenomenal that patients will now have the
opportunity to manage their PBC,” continues Deb. “We need
to get the word out that GE is making the test possible
nationwide, and I hope all hospitals and clinics make the
decision to get it.”
For more information about PBC and MRE, and to find out
how you can help spread the word, visit the following Web sites:
• pbcers.org
• www.mayoclinic.com/health/magnetic-resonanceelastography/MM00718
• www.liverfoundation.org
MRE Helps Guide Patient Management
Jayant Talwalkar, MD, hepatologist at the Mayo Clinic, uses
MRE as part of his evaluation in assessing patients with
known or suspected chronic liver disease to help determine
whether or not a patient should undergo an invasive liver
biopsy. “MRE provides additional assessment of liver disease
beyond routine lab and imaging tests,” he explains, “so we
can more appropriately refer for biopsy.”
Dr. Talwalkar believes the test enables him to assess more
patients who may need liver biopsy, and identify patients
who are likely to have fibrosis. Because liver biopsy is
invasive, some patients with suspected liver disease may
decline the procedure. As a result, in some cases, patients
with significant liver disease are not properly identified
as eligible candidates for appropriate treatment.
The test is particularly useful for patients afflicted with
Hepatitis B and C, which can often lead to liver injury.
22
SignaPULSE • Autumn 2009
Since MRE identifies tissue with elevated liver stiffness,
and advanced fibrosis or cirrhosis leads to increased liver
stiffness, patients with either type of liver disease can still
be evaluated and monitored.
“MRE is a better tolerated, noninvasive method to risk-stratify
patients who may have symptoms typical of fibrosis, such as
elevated liver stiffness,” he explains, “and we can evaluate
the need for biopsies, or wait to conduct that first biopsy
in the future when evidence typical of hepatic fibrosis first
presents on MRE.”
MRE, says Dr. Talwalkar, can provide additional information
that clinicians need to improve the management of their
patients with chronic liver disease. “Our long term goal is to
use the information downstream, to better utilize liver tests
and procedures and enhance the quality of patient care.”
The information contained in this document is current as of publication of the magazine.
GE Healthcare
Wide bore means
compromise, right?
Wrong.
Some have said that the benefits of a 70cm bore justified
making trade-offs in image quality. We disagree. So we’ve
developed an MR system featuring patient comfort,
productivity, and exquisite image quality. Now, you can
do wide-bore MR the right way — the Optima™ MR450w.
© 2009 General Electric Company
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
BREAST IMAGING
MRI Helps Save a Doctor’s Life
When a radiologist becomes the patient
It started out as a regular day for Dr. Donna Kessinger –
radiologist for the Huntington Medical Group in Long Island,
NY. But it ended up to be anything but normal.
Huntington was buzzing about the new Signa HDe 1.5T MRI
they had just received. According to Kessinger, some of the
Huntington Medical Group employees volunteered to be
scanned so the techs could learn to do a validation.
Kessinger has a history of dense breasts, and this was the
first time the clinic was able to do breast magnetic resonance
imaging (MRI) – so she volunteered for a breast MRI.
Kessinger has had yearly mammograms that showed no
problems and had a normal breast exam, so she wasn’t
anticipating the MRI would find anything. Unfortunately,
she was wrong.
24
SignaPULSE • Autumn 2009
With MRI and a contrast enhanced injection, Kessinger and
the team at Huntington were shocked to see a breast lesion.
The scan was followed up with an ultrasound for confirmation.
The clinic’s surgeon performed a biopsy and it was positive for
invasive ductal breast carcinoma cancer – about 1 centimeter
in size, poorly differentiated and HER2 positive – which meant
it was small but aggressive.
Another mammogram was done at the hospital – but
they couldn’t find or feel the lesion. “The fact that MRI
found it when it was small, at stage one, saved my life,”
says Kessinger. “I absolutely believe that.”
A bilateral mastectomy was performed. The pathologic
specimen measured 7 millimeters. Kessinger’s doctors
believed the cancer had been removed in its entirety
The information contained in this document is current as of publication of the magazine.
BREAST IMAGING
CLINICAL VALUE
Dr. Donna Kessinger
and there was no disease in her lymph nodes, but she was
put on a regimen of chemo and medications to prevent it
from spreading and recurrence.
it’s difficult to get authorization for MRIs on patients with
dense breast tissue,” states Kessinger. “It would be great if
there was an approved breast MRI screening process so the
clinic could do more scans, more quickly – perhaps a patient
every 20 minutes – and of course for a lesser fee. I am still a
strong advocate for yearly screening mammograms beginning
at age 35-40. It’s fast, inexpensive, and a successful modality
for early detection of breast cancer.”
Kessinger, 48 at the time, had no family history of breast
cancer. Thankfully, she tested negative for BRCA1 and
BRCA2, as she has three daughters and was concerned for
their futures. But Kessinger is now personally aware that
dense breast tissue can make it harder for doctors to spot
problems on mammograms. According to the American
Cancer Society (ACS), women with denser breast tissue have
more glandular tissue and less fatty tissue. As a result, they
may have a higher risk of breast cancer and smaller lesions
may be more difficult to detect on screening mammograms.
“There is a 10% false negative rate with screening mammograms, especially with dense breast tissue,” she says.
Kessinger is thankful that an ordinary day ended in a not
so ordinary way. “It shocks you to find something that you
weren’t aware was there – before you even felt a lump or
had a symptom. It’s a good thing, too – by the time I felt
it, it would have been too late. By the time this type of
cancer metastasizes, the cure rate is reduced dramatically,”
she comments.
“The experience has changed how I interact with patients.
I usually speak to my patients after their mammograms, to
discuss their results and they’re happy from hearing good
news, as I am happy to give the good news. But now when
I see dense breasts I want to order MRIs because of the 10%
false negative rate, however at this time in the United States,
Kessinger feels strongly that early detection and screening
is key for increasing the survival rate for breast cancer
patients. The ACS agrees – following are the organization’s
guidelines for early detection of breast cancer, found at
www.cancer.org. Please visit the Web site for additional
information, or call 1-800-ACS-2345. „
American Cancer Society Guidelines for Breast Cancer Screening
The American Cancer Society’s new guidelines for breast
cancer screening were introduced in March of 2007,
recommending magnetic resonance in addition to
mammography for a select population of women.
Specifically, it recommends breast MRI for women
who meet at least one of the following conditions:
• They have a BRCA1 or BRCA2 mutation;
• They have a first-degree relative (parent, sibling, child)
with a BRCA1 or BRCA2 mutation, even if they have
yet to be tested themselves;
• They had radiation to the chest between the ages
of 10 and 30; and
• They have Li-Fraumeni syndrome, Cowden syndrome,
or Bannayan-Riley-Ruvalcaba syndrome, or may have
one of these syndromes based on a history in a firstdegree relative.
The study details, references, sources, and guidelines
are available in the April issue of A Cancer Journal for
Clinicians, which is also available online at:
http://caonline.amcancersoc.org/cgi/content/full/57/2/75.
• Their lifetime risk of breast cancer has been scored at
20% to 25% or greater, based on one of several accepted
risk assessment tools that look at family history and
other factors;
A GE Healthcare MR publication • Autumn 2009
25
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
CARDIAC IMAGING
3D MR Free-Breathing Coronary
Artery Imaging Adds Value for
Assessing Congenital Heart Disease
By Wendy Strugnell, BAppSc(MIT), Director of MRI Services,
Queensland Centre of Excellence in Cardiovascular MRI
at Prince Charles Hospital
26
SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
CARDIAC IMAGING
While the detection of coronary artery lesions is the most
commonly considered application of coronary artery imaging,
a non-invasive technique for the evaluation of vascular
structures has significant value in assessing congenital
heart disease (CHD). For a number of conditions, a detailed
assessment of the proximal coronary arteries, the pulmonary
arteries, and their relationships with adjacent structures is
essential to guide surgical or therapeutic interventions
and to evaluate post-operative complications.
The new 3D Heart sequence from GE Healthcare is a
whole-heart 3D Fat Sat FIESTA technique for free-breathing
coronary artery imaging. It provides exquisite anatomical
detail and the volumetric acquisition makes it easier to
assess structures that have a tortuous course. This navigatorassisted, free-breathing technique may provide more
reliable results in patients who have difficulty with the long
breath-hold times of the 3D Fat Sat Fiesta sequence.
With 3D Heart, prospective slice-tracking based on navigator
echo is also used for prospective diaphragm motion correction
and can increase scan efficiency. The T2 preparation pulse
suppresses the myocardial signal and hence may improve
the contrast of the coronary arteries. A multi-slab acquisition
(MOTSA) option also allows easy whole-heart prescription,
improves inflow effect, and minimizes the effect of respiratory
drift and heart rate variability by completing each slab in
two to three minutes.
CLINICAL VALUE
The result is superb anatomical detail of the coronary
arteries acquired with 3D Heart in an axial oblique
acquisition (Figure 1).
Patients with CHD typically endure a lifetime of diagnostic
and therapeutic procedures and, therefore, the importance
of a comprehensive, non-invasive imaging assessment
without patient exposure to radiation dose cannot be
overemphasized. Magnetic resonance imaging (MRI) in CHD
plays an important role in the evaluation of CHD and the
addition of the 3D Heart sequence for particular clinical
indications has been promising in the management of
patients at our institution.
Protocol:
3D Heart
Patient position
Imaging parameters
Patient entry
Feet first
Imaging mode 3D
Patient
position
Supine
Pulse
sequence
FIESTA
Coil
configuration
8CARDIAC
Grad mode
Zoom
Scan plane
Axial or sagittal
PSD name
oblique
Imaging
options
Normal Coronary Arteries
Scan timing
3D Heart
Fast, EDR,
ECG, Nav,
ZIP2, ZIP512,
T2Prep, ASSET
Scanning range
Flip angle
90
FOV
Receiver
bandwidth
125 kHz
Slice thickness 2.2–2.4 mm
TR
N/A
Overlap locs
25% min
overlap
TE
Min Full
Locs per slab
18-20
Acquisition timing
Frequency
256
Phase
224-256
Frequency
direction
R/L
Phase FOV
1
NEX
1
30-35 cm
SAT
SPECIAL
ON
Figure 1. 3D Heart acquired in an axial oblique slab orientation shows the
superb anatomical detail of the coronary arteries in an adult patient with
normal coronary arteries.
A GE Healthcare MR publication • Autumn 2009
27
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
CARDIAC IMAGING
Clinical Cases
Pre-Percutaneuos Pulmonary Valve
Replacement Assessment
Case 1: Assessment of re-implanted
coronary artery origins
A female patient with transposition of great arteries (TGA)
repaired with an aorto-pulmonary switch procedure during
which the coronary arteries are reimplanted (Figure 2). 3D
Heart was performed as an axial oblique volume acquisition.
MIP image shows the origins of the coronary arteries free
of proximal stenoses.
Reimplanted Coronary Artery Origins
LAD
PV
Circumflex
artery
Ao
Ao=Aorta
PV=Pulmonary valve
LAD=Left anterior
descending artery
3a
Circumflex
artery
PV
LA
Figure 2. Origins of reimplanted coronary arteries demonstrated in a
patient with transposition of great arteries post-arterial switch repair.
Case 2: Pre-procedural assessment in patients being
considered for percutaneous pulmonary valve
replacement (PVR)
Patients with pulmonary atresia and tetralogy of Fallot who
have undergone repair with right ventricle to pulmonary
artery (RV-PA) valved conduit, pulmonary valvotomy/valvoplasty,
or tissue pulmonary valve replacement typically develop
pulmonary stenosis or incompetence. Pulmonary valve
replacement (PVR) is required to prevent the development
of right heart complications. In recent years, PVR has been
performed percutaneously. This technique may compromise
the left coronary artery if it lies directly adjacent to the
pulmonary valve or artery and, therefore, pre-procedural
assessment of this relationship is essential. Reformatted
MIPs from a sagittal oblique 3D Heart acquisition in a female
with repaired tetralogy of Fallot demonstrates the proximal
left anterior descending coronary artery coursing closely
behind and to the left of the pulmonary valve (Figures 3A, 3B).
28
SignaPULSE • Autumn 2009
LAD
PV=Pulmonary valve
LA=Left atrium
3b
LAD=Left anterior
descending artery
Figures 3a and 3b. Sagittal oblique 3D Heart acquisition in a female with
repaired tetralogy of Fallot reformatted into axial oblique (3A) and sagittal
oblique (3B) MIPs. The proximal left anterior descending coronary artery is
seen coursing closely behind and to the left of the pulmonary valve.
The information contained in this document is current as of publication of the magazine.
CARDIAC IMAGING
CLINICAL VALUE
Case 3: Assessment of pulmonary arteries in post-operative CHD
Wendy Strugnell
Morphological assessment of the proximal pulmonary arteries to determine the
presence of stenosis is required in post-operative tetralogy of Fallot or pulmonary
atresia, and in patients with TGA repaired by arterial switch procedure.
Figure 4 is a patient with TGA following arterial switch repair; the pulmonary
arteries have been relocated anterior to the ascending aorta. These arteries often
pursue a complex course and are difficult to image in 2D acquisitions. Stenosis of
the proximal left pulmonary artery is demonstrated in this MIP image of the 3D
Heart acquisition.
Assessment of Pulmonary Arteries in Post-operative CHD
Wendy Strugnell, BAppSc (MIT), is the director
of MRI Services at the Queensland Centre of
Excellence in Cardiovascular MRI at the Prince
Charles Hospital, Brisbane, Australia. Wendy has
been in MR radiography for more than 20 years
since graduating from the Queensland University
of Technology, Australia. She has authored and
co-authored numerous articles in peer-reviewed
publications and is actively involved in continuing
education for MR radiographers and technologists
worldwide. She is a member of the Section
for Magnetic Resonance Technologists of the
International Society for Magnetic Resonance in
Medicine and served as its 2008-2009 President.
About the facility
Figure 4. Stenosis of the left pulmonary artery is demonstrated in this
patient with transposition of great arteries post arterial switch repair.
In January 2002, Queensland Health established
the Centre of Excellence in Cardiovascular MRI
at the Prince Charles Hospital (Brisbane, Australia)
in partnership with GE Healthcare and the
Queensland University of Technology. The
centerpiece of this venture is the GE Signa®
Infinity Twinspeed 1.5T. The Centre aims to
promote and develop world-class research
initiatives in cardiovascular MRI, improve patient
management and care with faster, more accurate
diagnosis of cardiovascular disease and promote
MRI as integral to best practice in the delivery of
care to cardiac patients throughout Australia.
Summary
In the past, reliable and reproducible visualization of coronaries has been
a challenge due to cardiac and respiratory motion, poor signal-to-noise, and
contrast-to-noise ratios. 3D Heart is a great addition to the GE Healthcare cardiac
MRI portfolio. This patient friendly acquisition technique has, for the first time,
allowed us to generate excellent images of the proximal coronary and pulmonary
arteries without breath-holds or contrast agents and has a promising contribution
to make in the MRI assessment of some congenital heart diseases. „
A GE Healthcare MR publication • Autumn 2009
29
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
Renal Artery
MRA
By Anastasia L. Martin, R.T. (R) (MR),
Intermountain Medical Center
Discussion and diagnosis
High blood pressure, or hypertension, is the most common
cardiovascular disease1 and affects approximately one in
three adults in the United States.2 Hypertension is defined
as increased force or high pressure in the arteries as blood
courses throughout the body and is often referred to as
the “silent killer” because it rarely causes symptoms.1 If left
untreated, hypertension causes loss of function in both
kidneys and may ultimately lead to chronic renal failure.3
Untreated hypertension may also lead to stroke, heart
failure, vision problems, and difficulty with breathing.
Blood pressure is typically measured by placing a
sphygmomanometer around the upper arm to measure
pressure in the brachial artery.1 Experts in the field of
hypertension view normal blood pressure as less than
120 mm/Hg systolic and 80 mm/Hg diastolic.1 If the
pressure exceeds these levels, hypertension is diagnosed
and the clinician seeks to determine the cause.
There are two categories of hypertension.1 Hypertension
with undetermined underlying causes is classified as
essential hypertension and accounts for 95% of reported
cases in the United States. If a direct cause for high
blood pressure is identified, it is classified as secondary
hypertension. Kidney disease, renal artery stenosis, and
adrenal gland disorder are leading causes of secondary
hypertension.2 When the renal artery narrows, blood flow is
restricted to the kidney, stimulating the kidney to produce
a hormone known as Renin. Renin is a powerful blood
pressure regulator and increased levels initiate a series
of events that cause hypertension. Renal hypertension is
often suspected in younger hypertensive patients or in older
adults with sudden onset of hypertension.2 In cases where
renal artery stenosis (RAS) is severe, defined as greater than
70%, it may lead to renal vascular hypertension (RVH).3 RAS
and RVH can be difficult to manage, leaving the unaffected
kidney at risk of damage from overall hypertension.3
30
SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
VASCUL AR IMAGING
CLINICAL VALUE
Treatment
Essential hypertension is typically treated with
antihypertensive drugs and lifestyle modification in diet
and exercise. Secondary hypertension is often treated with
balloon angioplasty or stent placement. The procedure
restores adequate blood flow to the kidneys and lowers
blood pressure.4
It is important to note that kidney disease can be the
cause of hypertension and hypertension can be the cause
of kidney disease. Therefore, all patients with high blood
pressure should be evaluated for kidney and renal artery
disease.2 Magnetic resonance angiography (MRA) is often
the first approach to evaluate the renal arteries.
IFIR is easily prescribed by simply placing the imaging slab
over the kidneys (Figure 1). IFIR uses respiratory triggering
to eliminate the need for patient breath-hold. The sequence
does not require intravenous contrast, therefore, all timing
issues are also resolved.
Resp gate
IFIR Timing Diagram
TI 1000ms
Selective IR prep
SPIR
SSFP/FSE
Clinical case
Patient history
A 65-year-old was referred for a magnetic resonance
imaging scan to evaluate the cause for hypertension.
Contrast-enhanced MRA (CE-MRA) was requested to
visualize the renal arteries.
Volume 1: Acquisition
volume
Volume 2: IR prep volume
Figure 1
Methodology
CE-MRA is often the pulse sequence of choice to assess the
renal arteries. The sequence is a 3D Gradient Echo acquired
in the coronal plane with coverage of both kidneys and
associated renal arteries. The CE-MRA technique requires
an accurately timed contrast injection and utilizes either
centric or elliptic centric k-space filling. For optimal results,
the sequence typically requires a 25 second breath-hold.
Recently implemented MRA sequences are being used to
evaluate the renal arteries without breath-hold or contrast
injection. Inhance Inflow Inversion Recovery (IFIR) is a 3D
FIESTA based sequence that uses a selective IR pulse to
suppress background tissue and venous flow. Special
chemical saturation is applied to suppress fat signal.
In this patient case, a 3D CE-MRA sequence was performed
with a single dose of contrast injected at 2cc/second.
SmartPrep was used with the tracker placed in the
descending aorta at the level of the renal arteries. The
contrast timing was adequate; however, the patient could
not perform the 25 second breath-hold, resulting in MR
images with movement artifact and poorly visualized renal
arteries. The IFIR sequence was subsequently performed,
which requires applying respiratory bellows and placing a
slab over the renal arteries. The patient was instructed to
breathe normally until the acquisition was completed. The
resulting images demonstrate the full extent of the renal
arteries with no motion artifact, enabling the clinicians
to determine the patient has no renal artery stenosis.
A GE Healthcare MR publication • Autumn 2009
31
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
VASCUL AR IMAGING
Image comparison
Anastasia L. Martin
Anastasia L. Martin, R.T. (R) (MR) has been an
MRI technologist for the past eight months at
Intermountain Medical Center in Murray, Utah.
About the facility
Intermountain
Medical Center is the
largest hospital in the
Intermountain West
and the new flagship
of Intermountain
Healthcare.
Intermountain
Medical Center
serves as a major
adult referral center for six surrounding
states and more than 75 regional healthcare
institutions. It is a teaching hospital that works
in conjunction with the University of Utah
School of Medicine and area nursing colleges.
Medical education and research facilities and
clinics are part of the campus, as well as a new
physician office space building. Intermountain
Medical Center’s five sites, together with its other
supporting facilities, offer a careful balance
of seclusion and connection that makes the
campus effective and efficient.
CE-MRA images suffer from motion artifact. In particular, the accessory renal
on the left side cannot be visualized. The IFIR images and subsequent volume
rendered images exquisitely display the full length of the renal vessels and
accessory renal artery.
Protocols
CE-MRA
IFIR
TR (ms)
4.6
4.5
TE/TI (ms)
1.6
2.3/200
Bandwidth (kHz)
42
125
FOV (cm)
44x39
41x32
Thickness (mm)
2.8
2.0
Matrix (scan plane)
320x192 (coronal)
256x256 (axial)
NEX
0.73
0.79
Scan time (min)
0:25 breath-hold
3:53
Summary
Non-Contrast Enhanced MRA (NCE-MRA) provides excellent depiction of the renal
arteries in patients who cannot perform breath-hold imaging techniques. IFIR
provides a robust NCE-MRA technique that is useful in renal artery imaging. „
CE-MRA
IFIR
CE-MRA
IFIR
References:
1. Available at : http://www.webmd.com/
hypertension-high-blood-pressure/guide/
understanding-high-blood-pressure-basics
2. Available at: http://www.medicinenet.com/
high_blood_pressure/article.htm
3. Available at: http://www.nephrologychannel.com/
ras/index.shtml
IFIR
Volume Render
IFIR
Volume Render
32
SignaPULSE • Autumn 2009
Images courtesy of Intermountain
Medical Center, Murray, Utah
4. Blackwell G, Wann S, Kadekar S. Clinical Applications of
Cardiovascular Magnetic Resonance Methods. Journal of
Tehran University Heart Center 2006;1(3):125-136.
The information contained in this document is current as of publication of the magazine.
VASCUL AR IMAGING
CLINICAL VALUE
Inhance Inflow IR Allows
Robust, Contrast-Free Imaging
of the Renal Arteries
By Richard J. Friedland, MD, Director of Outpatient Imaging/DRA Imaging, Poughkeepsie, NY
Abstract
Inhance Inflow Inversion Recovery (IR) MR angiography
(MRA) provides an important innovative method of imaging
the renal arteries without the need for intravenous contrast.
Significant benefits of Inhance Inflow IR angiography are
that it is noninvasive, uses no ionizing radiation, and it is
not nephrotoxic. This technique combines and leverages the
advantages of new imaging hardware, advances in gradient
technology, advanced pulse sequence design, and parallel
imaging techniques to provide accurate, reliable, non-contrast
enhanced MR angiographic (NCE-MRA) images of the renal
arteries in a short scan time. The Inhance Inflow IR technique
allows NCE-MRA to regain a central role in the work up of renal
artery stenosis, particularly in the setting of renal insufficiency.
Introduction
Renal artery stenosis is the etiology of hypertension, as
well as chronic renal insufficiency in a small percentage
of patients with medically refractory hypertension.
Renovascular hypertension is the most common treatable
cause of hypertension. Prompt detection of renovascular
hypertension and subsequent endovascular treatment can
cure or improve hypertension and preserve renal function. It
is of paramount importance, therefore, to have an accurate
and reliable non-invasive screening examination to
diagnosis this condition.
Several implemented non-invasive techniques have
significant limitations screening for renal artery stenosis in
routine clinical practice. Ultrasound is limited due to the
location and oblique orientation of the vessels, which are
deep in the abdomen. While contrast-enhanced computed
tomography angiography (CTA) allows for excellent spatial
and temporal resolution, venous contamination and dense
arterial calcification, however, may still obscure visualization
of the underlying stenosis. CTA is also associated with
significant levels of radiation exposure, which is most
worrisome in young patients in whom detection of renovascular
hypertension is particularly important. Last, the use of
iodinated contrast material poses a risk of nephrotoxicity
especially in patients with underlying renal insufficiency.
Contrast-enhanced MRA (CE-MRA) has been considered
to be a remarkably accurate method of assessing the renal
arteries, yet it too is not without limitations. Errant bolus
timing, venous contamination, and renal parenchymal
enhancement can obscure segmental branches and may
limit evaluation of the renal arteries. Although time-resolved
contrast enhanced sequences such as TRICKS (Time Resolved
Imaging with Contrast Kinetic) have helped to reduce these
limitations, and dynamic contrast sequences demonstrate
renal flow dynamics, concerns over nephrogenic systemic
fibrosis have led to the use of CE MRA as a method of last
resort in patients with renal insufficiency.
The challenges of these methods, have reinvigorated interest
in NCE-MRA, including Phase Contrast (PC) and Time of
Flight (TOF) imaging. PC MRA gives both anatomic
information and quantitative information of flow dynamics;
however, the time required to acquire these images is
frequently unacceptably long for routine clinical use.
With TOF MRA, image quality and accurate visualization
of the renal arteries is hindered due to loss of signal from
in-plane saturation effects. Turbulent flow at the region of
the stenosis and the disordered flow in post-stenotic dilation
reduces image quality due to intravoxel dephasing. Like PC
MRA, TOF imaging consistently overestimates the degree of
stenosis leaving radiologists without a reliable, accurate,
non-invasive method for renal artery stenosis screening
in patients with renal insufficiency.
A GE Healthcare MR publication • Autumn 2009
33
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
Dr. Richard Friedland
Richard Friedland, MD, is the director of
Outpatient Imaging at DRA Imaging and a staff
radiologist at Vassar Brothers Medical Center. He
is vice president of the Medical Staff at Vassar
Brothers Medical Center. Dr. Friedland received
his medical degree from Albert Einstein College of
Medicine. He completed his radiology residency
at Montefiore Hospital Medical Center where
he was chief resident and completed his
postgraduate fellowship training at
Yale University.
About the facility
DRA Imaging, P.C., began more than 30 years
ago and has grown to include two private
imaging centers with 20 physicians, six physician
assistants, and over 150 support staff members.
The growth and success of its outpatient imaging
centers have enabled DRA to acquire the most
advanced diagnostic imaging tools available.
Time and again, DRA has been first to bring
the latest in medical imaging innovations
to the Hudson Valley.
From the beginning, the goal of DRA physicians
has been to combine cutting-edge technology
with compassionate patient care. These
objectives have been brought together to make
up the corporate vision statement, which all
members of DRA Imaging are proud to maintain:
“Leaders of Diagnostic Imaging, Champions
in Patient Care.”
34
SignaPULSE • Autumn 2009
VASCUL AR IMAGING
At our facility, the use of Inhance Inflow
IR MRA helped foster collaboration between
the radiologist, nephrologist, and cardiologist,
and facilitates safe, timely evaluation and
prompt treatment of renal artery stenosis
by returning NCE-MRA to a central role
in screening for renovascular hypertension.
Dr. Richard Friedland
Inhance Inflow IR overcomes prior NCE-MRA limitations
A new NCE-MRA sequence, Inhance Inflow IR MRA provides reliable, accurate,
and robust imaging without intravenous contrast. Inhance Inflow IR, a novel
combination of pulse sequences and techniques, overcomes prior limitations
of NCE-MRA. Background suppression is achieved by saturating arterial blood,
venous blood, and lipids with an inversion pulse. Data acquisition occurs after
an inversion time, which allows the background and venous blood to reach
null point, while the fresh inflowing arterial blood has full magnetization
as it is not affected by the inversion pulse.
To enhance the fat suppression and increase the visibility of the arterial signal,
a spectrally selective inversion recovery pulse (SPECIAL) is applied in addition
to the inversion pulse. Both the high signal of blood observed with 3D FIESTA
and the fresh spins of high velocity inflowing arterial blood help create the
angiographic image. Using this sequence of pulses significantly reduces background
signal while exquisitely delineating the renal vasculature. The robust background
signal suppression of the Inhance Inflow IR sequence allows for routine
assessment of segmental branches as they course through the renal hilus.
Additionally, there is no fluoro triggering or Smart Prep, and no venous contamination
of arterial vessels. Respiratory gating allows free breathing, which maximizes
patient comfort while minimizing breathing artifacts. Unlike breath-hold imaging,
this respiratory-triggered sequence allows the time to acquire high-resolution
images by using ASSET acceleration to decrease the acquisition time.
Image acquisition with Inhance Inflow IR MRA is straightforward and simple. After
a scout image is obtained, the field of view is positioned over the renal arteries
and kidneys and image acquisition commences. The exam is typically performed
in four to five minutes and the raw data can be rapidly post processed for viewing.
At our facility, the use of Inhance Inflow IR MRA helped foster collaboration
between the radiologist, nephrologist, and cardiologist, and facilitates timely
evaluation and prompt treatment of renal artery stenosis by returning NCE-MRA
to a central role in screening for renovascular hypertension. Inhance Inflow IR
MRA provides an exceptional imaging solution for patients with hypertension and
renal insufficiency. The sequence is also well suited for vascular evaluation in the
post-renal transplant patient, who often requires repeat periodic surveillance
renovascular imaging. This also helps diminish referring clinicians’ concerns
regarding nephrotoxicity of conventional iodinated contrast for this
post-transplant patient population, as gadolinium-based MRA precludes
evaluation for these patients. „
The information contained in this document is current as of publication of the magazine.
VASCUL AR IMAGING
CLINICAL VALUE
Figure 1. A diabetic male with new onset hypertension was referred for
MRA to rule out renal artery stenosis. One set of Inhance Inflow IR images
was acquired on a GE HDe magnet in under 5 minutes. Renal artery
stenosis is expeditiously excluded. Note the exquisite detail of the renal
hilar vessels.
Figure 2. Male with diabetes and new onset hypertension referred for MRA.
Excellent visualization of the main renal arteries and the left accessory
renal artery confidently excludes renal artery stenosis.
Figure 3. Female post renal transplant with new onset hypertension. The
patient was sent to rule out stenosis of transplant vessel. Images were
acquired in less than 5 minutes on a GE HDe magnet. The transplanted
main renal artery and the branching renal vessels are well demonstrated
and are without significant stenosis.
Figure 4. Woman with diabetes and new onset hypertension referred
for MRA. MRA acquired in less than 5 minutes on a GE HDe magnet. No
evidence of renal artery stenosis. Superb definition of the early bifurcation
of the right main renal artery.
A GE Healthcare MR publication • Autumn 2009
35
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
MSK IMAGING
Game On:
With the XXI Olympic/Paralympic
Winter Games Around the Corner,
Radiologists are Gearing up
Here’s a little-known fact: While the summer Olympics
has more than three times the amount of athletes than
its winter counterpart, it’s actually the winter Olympics that
sees more severe trauma in its athletes. Even more strange?
Not until this year’s Winter Games will athletes at all venues
have dedicated access to magnetic resonance (MR)
imaging. Coordinating and organizing world-class care
for world-class athletes takes someone who’s knowledgeable
and respected in the field of MSK imaging. Enter Bruce Forster.
Forster, MD, FRCPC and professor and vice chair (research)
at the University of British Columbia in the Department
of Radiology, is the manager of diagnostic imaging for
the 5,000 athletes at the Olympic/Paralympic Winter
36
SignaPULSE • Autumn 2009
Games being held in Vancouver, British Columbia
in February-March 2010. It requires managing a team
of 20 radiologists from across Canada for both Games.
“Athletes are sliding on snow and ice and that means there’s
less control than athletes have in other sports,” Forster
explains. “The trauma is more high end. There’s a risk
of high-speed collisions between the athletes and ice which
can result in spinal cord injuries, fractures, and dislocations.”
As if that’s not enough to put anyone on high-alert,
the sliding center in Vancouver is designed by the same
architect as the world-record setting Turin sliding center,
so times – and injuries – can both set records.
The information contained in this document is current as of publication of the magazine.
MSK IMAGING
CLINICAL VALUE
Dr. Bruce Forster
“The trauma is more high end.
There’s a risk of high-speed collisions
between the athletes and ice which
can result in spinal cord injuries, fractures,
and dislocations.”
Dr. Bruce Forster
To anticipate the needs of the athletes, Forster says they are
dedicating two Signa HDxt 1.5T MR systems for the athletes,
one in Vancouver and one in Whistler – a move, he says,
that will avoid conflict between the publically funded system
and private athletes. Of the 800 to 900 exams anticipated,
one-third of them are expected to be MR.
“Of all the services offered in the polyclinic, diagnostic
imaging is the second most in demand,” he says. “Dentistry
is number one.”
In addition to MR systems, the winter Olympics/Paralympics
will offer GE’s portable ultrasound at five selected venues
to immediately assess athlete injury at the field-of-play
and determine, on the spot, if they can return to competition.
Bruce Forster, MD, is professor and vice-chair
(research), in the Department of Radiology,
University of B.C. in Vancouver, Canada; Regional
Director of MRI for Vancouver Coastal Health; and
Medical Director, Canada Diagnostic Centres (B.C.).
He serves as an Associate Editor for the journal
Radiology, and the British Journal of Sports Medicine,
is a member of the International Skeletal Society,
and serves as Chair of the Educational Committee
for the Canadian Association of Radiology. As an
associate member of the renowned Allan MacGavin
Sports Medicine Clinic, he participates in clinical,
research, and educational activities for radiology,
sports medicine, and orthopedic surgery residents.
Although he serves as imaging manager for
Vancouver 2010, Dr. Forster admits his own
record in sporting events is decidedly checkered.
A GE mobile medical unit similar to what was used in the
Katrina tragedies will also be on site, complete with an OR,
a four-bed ICU, and a four-bed PAR. “We hope we don’t
have to use it, but if there’s something as unfortunate
as a rock slide, we need to be prepared.”
Another first for this year is the usage of digital dictation
and voice recognition. “We’ll be producing an electronic
medical record and the report burned to CD,” Forster
says, “so the athletes can leave with a disk of their images
and the dictation within an hour of completing their
imaging study.”
And this is just in preparation for the Olympic/Paralympic
Winter Games! Stay tuned for a re-cap from Dr. Forster
in the next issue of SignaPULSE. „
A GE Healthcare MR publication • Autumn 2009
37
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
Tips From the Technologist:
Easy Steps for Ankle Imaging
By Tony Issa, Chief MRI Radiographer,
Norwest Medical Imaging
Technique
At our facility, we perform a large number of musculoskeletal
MRI exams on elite athletes. One of the more difficult joints
to scan effectively is the ankle, which is due to its many
ligaments and tendons, not to mention the different angles
needed to image around the ankle.
To ensure that we obtain consistent results of ankle MR
studies, we use the technique described below and have
found it gives us extremely reproducible results, as well
as good demonstration of the anatomy.
Step 1:
The ankle is scanned using the transmit receive ankle
coil, which makes the positioning easy, reproducible,
and comfortable for the patient.
Step 2: Axial PD and PD fat sat
Next we use the 3-plane localizer and from there, we can
plan the axial (or long-axis) views.
Axial PD/PD fat sat: No angulation of the block is used if the
ankle/foot is straight, otherwise we angle along the plantar
of the foot. The angle is determined by the degree of
the plane of the foot.
Both PD and PD fat sat are scanned in this plane making
it easy to copy the prescription forward.
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SignaPULSE • Autumn 2009
Figure 1. Note slice angles for axial
(short axis) PD and PD Fat Sat.
Figure 2. Resulting PD axial
The information contained in this document is current as of publication of the magazine.
MSK IMAGING
CLINICAL VALUE
Step 3 : Sagittal PD and PD fat sat
Proper angulation of the ankle perpendicular to the talar dome and the malleoli is
necessary. Once the angle is determined, another angulation along the calcaneous
and tarsal bones is required, to reduce distortion of the ankle/foot in the sagittal
plane. Achieving these two angles to the best of your ability will reduce this
distortion and place the ankle and foot in the correct plane. A good reference
to determine whether the angles are correct is to review structures such as the
sinus tarsi. Again, we use Copy Rx when scanning a PD and PD fat sat so we can
plan once and copy the prescription forward.
Figure3. Coronal ankle (note the
slice positions)
Tony Issa
Tony Issa, chief MRI radiographer at Norwest
Medical Imaging, studied at the University of
Sydney, where he completed a degree in Applied
Science Diagnostic Radiography. Issa joined
Norwest Medical Imaging 18 months ago and
was responsible for starting their very busy MRI
department. Issa specializes in MSK imaging,
always striving for the very best image quality.
Figure 4. Resulting sagittal
ankle plane
Step 4 : High-resolution talar dome
Using a properly acquired sagittal and axial image, a block of fine slices is placed
over the talar dome area. A reverse angle running perpendicular to the dome on
the sagittal image and parallel along the axial image of the dome is applied. This
angle can vary between 7 and 10 degrees depending on the patient’s anatomy
and position.
Figure 5. Note the angle of the
slices through the talar dome.
About the facility
Norwest Medical Imaging is an independently
owned, state-of-the-art radiology practice that
has been in operation for two years. Located
in the Hills area of Sydney, Australia, it boasts
first-class premises, equipment, and staff.
Continuing their commitment to state-of-the-art
imaging services, Norwest Medical Imaging is
proud to announce the installation of a new
1.5T GE Signa MRI scanner at their facility.
Figure 6. Resultant coronal PD
small FOV
By utilizing this technique, we can generate an excellent image of the talar dome
that will help us examine the medial and lateral aspects of this anatomy. Pathology
such as talar dome lesions and chondral wear in the joint area are common and
clearly depicted with this sequence. Furthermore, orthopedic specialists use these
images to examine the medial corner of the dome, where arthroscopy often fails
to clearly show pathology, making this MRI sequence extremely useful.
By following this technique, we are able to produce consistent, high quality images
of the ankle for our radiologists. „
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
MSK
DWI Demonstr
Strong Clinical
and Soft Tumo
By Carlo Faletti, MD, Radiology Department Chief, Tiziana Robba, MD,
Guido Regis, MD, CTO Hospital, Turin and Valeria Clementi, PhD,
Advanced Application Specialist, GE Healthcare
Magnetic Resonance Imaging (MRI) is the method of choice
for the diagnostic work-up of soft tissue and bone tumor. Traditionally,
anatomical T2, T1, and PD weighted images are used in tumor
characterization, monitoring treatment, and evaluating changes
in tumor size and contrast enhancement. The ability of MRI to
highlight common benign lesions, such as lipoma and hemangioma,
assists in determining a conclusive diagnosis.
MRI is well established as an excellent diagnostic tool for determining
the location and extent of soft tissue tumors. Sarcomas can also
be well defined based on the location, morphology, and tissue
signal contrast. However, in a large number of soft tissue tumors,
MRI provides limited information regarding malignancy grade
and histotype.
Diffusion-weighted imaging (DWI) is an imaging method that
supplies information on water proton mobility, and has been used
successfully for acute stroke diagnosis and characterization of brain
tumors. DWI studies of tumors outside the brain have also been
recently reported in the scientific literature, including use
in musculoskeletal radiology studies.
Based on the results of these studies, there is strong potential
for the clinical application of DWI in musculoskeletal radiology,
mainly for lesion characterization and to evaluate tumor response
to therapy. To test this potential clinical role, we included DWI
sequences during the MR standard protocol for stadiation of soft
tissue and bone tumors before the surgical treatment. Then,
we compared the ADC maps with the histological exam result.
Our experience with adding the DWI acquisition during standard
clinical protocol was simple and fast. „
40
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The information contained in this document is current as of publication of the magazine.
MSK IMAGING
CLINICAL VALUE
rates
Utility for Bone
r Diagnosis
Case 1. Myxoid lyposarcoma
Forty-six-year-old patient with left shoulder indolent mass
underwent a shoulder MRI.
The ADC map shows high ADC values (Figure 1c, red),
appearing as typical for myxoid lesions. The histological exam
confirmed abundant myxoid matrix that was mucinous and
water rich.
Protocol:
System: GE Signa HD 1.5T
Axial T2w: FRFSE-XL, TR 3540, TE 105/Ef, 31.2 kHz,
FOV 21x21 cm, 7/0.7 mm, 320x224, 4NEX
Axial DWI: SE/EPI, TR 4850, TE 82.2, FOV 22x22 cm,
7/0.6 mm, 128x128, 6NEX, b=0 and 800 s/mm2
Figure 1b. Axial T2w image reveals the lesion.
Figure 1a. Typical histological image
of myxoid matrix
Figure 1c. Axial ADC color map (scale: 0.0004-0.002 mm2/s),
superimposed on the DWI image, demonstrates the high
ADC values (red) on the lesion.
A GE Healthcare MR publication • Autumn 2009
41
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
MSK IMAGING
Case 2. Ewing sarcoma
Prof. Carlo Faletti
Carlo Faletti, MD, is director of the Department
for Imaging in the Orthopaedic Hospital and
Trauma Centre, CTO- M. Adelaide, in Turin.
Prof. Faletti received his medical degree in
Radiology from Turin University. He currently
serves as Professor of Musculoskeletal
Radiology, at the Specialty School of Radiology
of the Universities of Turin, Novara, Genova
and Rome (Tor Vergata); as well as Professor
of Musculoskeletal Radiology, at the Specialty
School in Orthopaedics and Traumatology and
Physiotherapy at the University of Turin; President
of the Italian Society of Radiology in Sport
Medicine; and President of the subcommittee
in Sport Medicine Imaging of the European
Society Skeletal Radiology.
Sixteen-year-old patient presented with left thigh pain and swelling. Radiographic
exam showed a lytic lesion of left femoral proximal shaft.
The histological exam confirmed an Ewing tumor. The ADC map shows very
low ADC values (Figure 2c, cyan-green), corresponding to the lesion. Low ADC
values are due to packed cells with virtually absent matrix (high cellularity, as
shown by histological specimen) that restricts free water diffusion.
Protocol:
System: GE Signa HD 1.5T
Axial T2w: FRFSE-XL, TR 3360, TE 123/Ef, 41.7 kHz, FOV 40x40 cm, 9/1 mm,
384x320, 2NEX
Axial DWI: SE/EPI, TR 4850, TE 82.8, FOV 22x22 cm, 8/0.8 mm, 128x128,
6NEX, b=0 and 800 s/mm2
Dr. Tiziana Robba
Figure 2a. Typical histological
image of Ewing tumor
Figure 2b. Lesion is clearly depicted on axial
T2w image.
Tiziana Robba, MD, is a radiologist in the
Diagnostic Imaging Department of CTO Hospital
in Turin. Her primary interest is musculoskeletal
oncology. Dr. Robba received her medical degree
in Radiology and Science of the Imaging from
Turin University.
Figure 2c. Axial ADC color map
(scale: 0.0004-0.002 mm2/s), superimposed on
the DWI image, demonstrates the low ADC values
(cyan-green) on the lesion.
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
MSK IMAGING
CLINICAL VALUE
Case 3. Anaplastic soft tissue sarcoma
A thirty-seven-year-old patient with posterior tight mass diagnosed
as anaplastic sarcoma from histological study. During the first phases
and end of pre-operative chemotherapy, we observed tumor shrinkage and
necrosis of solid neoplastic tissue; consequently, the ADC values increased.
Protocol:
System: GE Signa HD 1.5T
Axial T2w: FRFSE-XL, TR 3540, TE 111/Ef, 16.7 kHz, FOV 22x22 cm, 5/0.5 mm,
224x192, 2NEX
Axial DWI: SE/EPI, TR 4850, TE 77.1, FOV 22x22 cm, 5/0.5 mm, 128x128,
6NEX, b=0 and 800 s/mm2
Dr. Guido Regis
Guido Regis, MD, oversees CT and MRI
in the Diagnostic Imaging Department of CTO –
M. Adelaide Hospital, Turin. His area of specialty
is primarily focused on musculoskeletal
pathology and oncology.
Dr. Regis received his medical degree in
Radiology and Science of the Imaging and
Specialisation in Orthopaedics/Traumatology
from the Turin University.
Dr. Valeria Clementi
Valeria Clementi, PhD, is an MR advanced
application specialist for GE Healthcare.
Dr. Clementi recieved her physics degree,
specializing in medical physics and her PhD
in biochemistry from Bologna University.
Figure 3a. Axial ADC color map (scale: 0.0004-0.002 mm2/s),
superimposed to the T2w image, demonstrates the low
ADC values on the lesion (cyan-green) during the first
phases of chemotherapy.
About the facility
The Orthopaedic Hospital and Trauma Centre,
or CTO – M. Adelaide, of Turin, Italy, is a Trauma
and Orthopaedic Center and site of the Turin
Specialty School on Orthopaedics and
Traumatology and on Occupational Medicine.
It is also a reference site for the Piedmont Cancer
Network for bone and soft tissue sarcomas.
It currently operates three GE MR and two
GE CT systems.
Figure 3b. Axial ADC color map (scale: 0.0004-0.002 mm2/s),
superimposed to the T2w image, demonstrates increasing
ADC values on the lesion (red) after the end of chemotherapy.
A GE Healthcare MR publication • Autumn 2009
43
The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
M R I N P S Y C H I AT R Y
Unlocking the Mysteries
of the Mind
Understanding the human brain through neuroimaging is the life work of
Wayne Drevets, MD, president and director of the Laureate Institute for
Brain Research (LIBR). Together with Jerzy Bodurka, PhD, MRI facility director
at LIBR, he hopes to transition use of magnetic resonance imaging (MRI) in
psychiatric applications from research to clinical practice, to more quickly
and objectively diagnose patients and assess therapy.
Prior to joining LIBR, Drs. Drevets and Bodurka worked at the National
Institutes of Health (NIH), where they researched neuropsychiatry using
fMRI to understand the brain’s response to stimuli and identify anatomic
changes and cellular abnormalities.
“Today, the field largely uses MRI to exclude a diagnosis that may
masquerade as a psychiatric disorder,” says Dr. Drevets. He hopes
to change this at LIBR with the installation of the Discovery
MR750 3.0T system.
Dr. Bodurka is equally optimistic. “Until now, commercially
available 3.0T MRI scanners could not process in
real time the large amount of data generated in
a high resolution whole brain fMRI scan with
multi-element coils array,” he says. “However, we
believe that the Discovery MR750 might be the
first 3.0T scanner to provide the level of power,
speed and reliability we need for clinical
applications in psychiatry.”
Several technological advancements,
Dr. Bodurka notes, enable the leap to
real-time fMRI. “The Discovery MR750
delivers whole body gradients with the
highest power and fidelity available on a
commercial scanner, while the advance
thermal management effectively reduces
issues associated with gradient heating.
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
M R I N P S Y C H I AT R Y
“Furthermore, the new generation digital multichannel MRI receiver with an
optical data architecture located in the MR room provides a signal-to-noise gain
not found [today] on other commercially available 3.0T MR systems,” Dr. Bodurka
adds. “With the nonlinear system drift over time limited to less than 0.1%, the
MR750 offers a unique combination of excellent system power and temporal
stability that should help reliably capture and accurately measure subtle
changes in hemodynamic activity during human brain mapping with fMRI.”
Connecting science with practice
With between 3,000 to 4,000 inpatient admissions and more than 80,000 outpatient
visits yearly, LIBR offers Drs. Drevets and Bodurka the opportunity to test, assess,
and follow a large population of patients longitudinally who suffer from
depression, anxiety, eating, and memory disorders.
“We have some evidence that we can use real-time fMRI to help teach healthy
individuals to modulate their response to stimuli,” says Dr. Drevets. The Institute seeks
to apply this knowledge to patients with depression, which affects 150 million
people worldwide and is ranked by the World Health Organization as the
leading cause of years of life lived with disability for all ages.
But their vision goes far beyond this. “Our goal at Laureate is to transition the
use of MRI in psychiatric applications from research to clinical practice so we
can more quickly and objectively diagnose patients and assess therapy,” says
Dr. Drevets. “We also hope to identify people who are at risk for developing certain
neurological diseases or psychiatric disorders so that we can intervene earlier
in the illness course to prevent or reduce chronic disability.”
Figure 1. Composite neurofunctional fMRI map showing motor (red),
language (green), and visual (purple) activation.
CLINICAL VALUE
Dr. Jerzy Bodurka
Jerzy Bodurka, PhD, is an MRI physicist and
director of the Functional MRI Facility at the
Laureate Institute for Brain Research in Tulsa,
Oklahoma. He received his doctorate degree in
physics from the University of Nicolaus
Copernicus in Torun, Poland, and completed part
of his postdoctoral training in Nuclear Magnetic
Resonance at the Department of Chemistry at
Free University of Berlin, Germany. Dr. Bodurka
completed his postdoctoral fellowship training
in functional MR imaging at the Department of
Biophysics at the Medical College of Wisconsin
in Milwaukee. In 2000, he joined the NIMH/NIH
Functional MRI Facility as a principle MRI physicist;
he left NIH to assume his current role at Laureate
in July, 2009. Dr. Bodurka is a recipient of NIH
Director Award for advancing brain MR imaging
by development of array detectors and
implementation of parallel imaging.
Dr. Wayne C. Drevets
Wayne C. Drevets, MD, became the Oxley
Professor of Psychiatry at Oklahoma University
Health Sciences Center (OUHSC) in Tulsa and the
director and president of the Laureate Institute
for Brain Research (LIBR) in July, 2009. Dr. Drevets
previously worked in the NIMH Intramural
Research Program, where he served as
Senior Scientist and Chief of the Section on
Neuroimaging in Mood and Anxiety Disorders
since 2001, and Acting Chief, Laboratory on
Molecular Pathophysiology since 2008. Prior to
2001, he held appointments in Psychiatry at the
University of Pittsburgh School of Medicine for
four years and the Washington University School
of Medicine for nine years. Dr. Drevets received
his MD degree from the University of Kansas, and
completed residency training in psychiatry and
post doctoral fellowship training in imaging
sciences at Washington University. Dr. Drevets’
research focuses on applying positron emission
tomography (PET) and magnetic resonance
imaging (MRI) to characterize the
pathophysiology of mood disorders.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
M R I N P S Y C H I AT R Y
With family history coupled with annual or biannual MRI assessments, LIBR
clinicians hope to detect changes in the brain’s gray matter, an indication of
psychiatric disorder, in patients believed at high risk for disabling psychiatric
disorders. “At NIH, we discovered that cases with the smallest amount of gray
matter in brain regions known to regulate emotion were those patients who
became chronically ill from major depressive disorder,” explains Dr. Drevets.
About the facility
The Laureate Institute for Brain Research
opened May 1, 2009 and currently houses a
multidisciplinary team of scientists and clinical
research staff who will apply neuroimaging,
genetic, pharmacological, and neuropsychological tools to investigate the biology of
neuropsychiatric disorders. The Institute’s
creation was supported by the W.K. Warren
Foundation for the purpose of conducting
studies aimed at developing more effective
treatments or prevention strategies for these
disorders. The studies will be led by scientists
from diverse backgrounds, including physics,
cognitive neuroscience, psychology, psychiatry,
developmental neuroscience, computer science,
and genetics.
To accomplish this, the LIBR team will combine their specially designed
multi-element (16-, 32-channel) head coils with the Discovery MR750’s fast
reconstruction engine, parallel imaging techniques, and redesigned system
architecture to maximize signal and speed.
Researchers and clinicians at Laureate are also considering the potential in using
real-time fMRI to teach patients with depressive or anxiety disorders to more
effectively modulate their own responses to emotional thoughts or stimuli. This
approach to treating depression conceivably may potentially lead to additional
understanding for alternative therapy.
Other research being conducted at Laureate investigates in patients who are
being treated for depressive disorders whether an fMRI exam that measures
patient response to specific emotional paradigms may allow the clinician to
objectively assess treatment efficacy within just a few days after treatment was
first initiated. Currently, it takes an average of six weeks to assess the response
on clinical signs and symptoms.
The facility plans to use GE’s advanced MR applications such as Cube or BRAVO
for structural imaging. Resting state fMRI will help to map brain functional
connectivity while Diffusion Tensor Imaging techniques will be used to visualize
white matter trajectories. EPI/BOLD sequences, specifically designed paradigms,
and sophisticated postprocessing applications will be deployed to capture and
analyze complex, multistate eloquent cortex activations. To increase specificity
for some applications, BOLD fMRI responses will be correlated with patients’
other physiological parameters.
Drs. Drevets and Bodurka anticipate their research and clinical efforts can
change the way certain psychiatric diseases are diagnosed and managed. „
Figure 2. The BrainWave interface provides the
capability to view fMRI results on 3D renderings or
orthogonal slices. A simple motor task is presented
in orange and yellow colors in the above screen.
46
SignaPULSE • Autumn 2009
Figure 3. BrainWave also provides the flexibility to
overlay Fractional Anisotropy maps on the orthogonal
slides, create composite maps with multiple fMRI
studies and the ability to combine those results
with fibers tracked from DTI acquisitions.
The information contained in this document is current as of publication of the magazine.
By Leslie C. Baxter, PhD, Staff Scientist
and Clinical Neuropsychologist, Barrow
Neurological Institute
Presurgical mapping using functional
magnetic resonance imaging (fMRI) in
patient populations with neurological
impairment can be challenging. Some
of the challenges and potential solutions
are discussed here within the context
of our experience with presurgical fMRI
mapping of adults and children at
Barrow Neurological Institute at St.
Joseph’s Hospital and Medical Center
in Phoenix, AZ.
Because of Barrow’s philosophy of
providing minimally invasive surgical
interventions, presurgical mapping
using fMRI has become an integral
part of surgical planning for patients
with brain tumors, aneurysms, anterior
venous malformations, and other
lesions that may impact cognitively
eloquent regions.
All fMRI scans at Barrow are done on
a 3.0T GE Signa HDxt scanner using
an 8-channel head coil. Patients are
referred for fMRI both as outpatients
and inpatients, with most referrals
received on an outpatient basis within
one week of the planned surgery. For
each exam, it is important that the
patient understands and is able to
participate with the tasks. Tasks are
modified using step-down versions or
other alterations depending on the
level of impairment and other factors
that can vary among patients. The
structural scans used for neuronavigation
within the surgical suite are acquired
Special Considerations
When Using Functional MRI
as a Presurgical Mapping Tool
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
Dr. Leslie Baxter
NEURO IMAGING
in the same imaging session. fMRI data is analyzed and co-registered to the
stereotactic image (either T1 or T2 scans) and uploaded to a Picture Archiving
and Communication System (PACS) and sent to the operating room (OR). These
evaluations are typically done several days prior to the surgery to allow for
review and consultation with the treating physicians.
Scanning strategies for maximum results
Leslie Baxter, PhD, is an associate staff scientist
and clinical neuropsychologist and directs the
Neuropsychology Neuroimaging Laboratory in
the Section of Clinical Neuropsychology at
Barrow. She is also the principal investigator for
the Barrow site of the multi-institutional Arizona
Alzheimer’s Research Consortium. Dr. Baxter
received a bachelor’s degree from the University of
Michigan, a doctorate in Clinical Neuropsychology
from the Chicago Medical School, and she completed
a post-doctoral fellowship at Dartmouth.
Using state-of-the-art neuroimaging techniques,
functional MRI and Diffusion Tensor Imaging,
the Neuroimaging Lab studies both functional
recovery and deterioration of the brain. Dr. Baxter
also uses these techniques for clinical purposes
to map cognitive functioning in brain tumor
patients before they undergo surgery. She
personally performs all of the exams to ensure
that the patient understands and is able to
participate with the tasks.
Stimulus presentation
There are several commercially available choices for presenting the tasks to
patients. These range from back-projection systems, in which the stimuli are
presented so that the patient can see the information on a mirror attached to
the head coil, to a number of different goggle and headphone packages. The
preference at Barrow is to use a goggle/headphone system for a number of
reasons specific to working with patients, especially children. Unlike research
volunteers, many patients have MRI-related anxiety, or even mild claustrophobia,
and some have not previously had a scan without the use of sedating medication.
We have found that many of these people are more relaxed when they have a
limited view of the interior of the scanner. We have pictures of outdoor scenes
(as well as a variety of “themed” pictures depending on the person’s interests)
that help the patient focus on something other than the scanner and also give an
illusion of being in a more open environment. For children, we have had the best
results when playing a cartoon or movie through the goggle system. Sometimes,
it is best to have the movie running prior to sliding the head coil over the head of
the child. We have found in our research study of children with traumatic brain
injury that playing a children’s movie, such as “Shrek,” allowed us to perform
approximately 45 minutes of structural scans, including a 10 minute high-resolution
T1 scan, without any movement difficulties. (In fact, children with Attention Deficit
Disorder were some of the least fidgety participants when they are watching
movies.) Headphones allow for easier communication with the patients and
the ability to present tasks aurally.
About the facility
The Barrow Neurological Institute of St. Joseph’s
Hospital and Medical Center in Phoenix, AZ, is
internationally recognized as a leader in
neurological research and patient care.
Established in 1962 under the auspices of
Dr. John Green, Barrow has been brought
into the twenty-first century under the
guiding influence of Dr. Robert Spetzler.
A 430,000 square foot tower dedicated to
neurosciences opened at St. Joseph’s in 2006.
With 11 neurosurgical operating rooms and
the first 3.0T GE intraoperative scanner, the
Barrow has a focus on providing state-of-the-art
neurosurgical interventional care.
Barrow treats patients with a wide range of
neurological conditions, including brain and
spinal tumors, cerebrovascular conditions,
and neuromuscular disorders.
U.S. News and World Report’s 2009 “Best Hospitals”
ranking once again includes St. Joseph’s Hospital
and Medical Center.
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SignaPULSE • Autumn 2009
Participant cooperation and quality control
At our center, patients are given a short visual task that consists of blocks of
scenic pictures alternating with a crosshairs to produce real-time images of fMRI
activity in the occipital lobe. This task accomplishes several goals for us. First, we
take advantage of the BrainWave RT “real time” feature on the GE scanners to
provide us with real-time quality control. The activation associated with the
primary visual cortex is quite strong and generates good occipital lobe activity
even with one “on-off” cycle; therefore, if a lack of activity is detected, we can
immediately investigate any possible reasons, including equipment failure,
patient cooperation (movement, somnolence, etc.), or other factors that can
be corrected.
Because it requires no cognitive cooperation from patients beyond keeping their
eyes open, it allows us to make these basic system checks without confounding
cognitive factors. This task is also relaxing to most patients, which allows them to
acclimate to the scanner noise and fMRI procedure. Since pediatric patients are
frequently anesthetized during MRIs, this may be the first time they experience
the scanner environment and they often benefit from this acclimation period.
The information contained in this document is current as of publication of the magazine.
NEURO IMAGING
CLINICAL VALUE
Task choice
Task choice varies across institutions, but in general, presurgical
referrals tend to be for motor, language, and vision mapping.
There are considerations for the development of fMRI tasks
for clinical use that differ from research applications based
on the fact that patients who need presurgical mapping are
more likely to have difficulties tolerating the MRI procedure.
Therefore, the goal is to design a task that activates the
cognitive target in the shortest possible amount of time to
maximize patient cooperation. This is especially important
with children due to their limited attention span. At Barrow,
we have developed a number of tasks with “step down”
versions so that we can attempt to elicit responses in patients
who may be somewhat compromised but still able to be
examined. (Although it may be possible to assess certain
abilities such as motor and vision function in patients who
have limited language skills through vocal directions, a
general rule of thumb is that a basic understanding of
language and ability to independently perform a task
for a short period of time is necessary to successfully
obtain fMRI results.)
Task analysis and interpretation
fMRI results for presurgical mapping are overlaid on highresolution 3D T1-weighted post-contrast scans that are used
for neuronavigation in the OR. We load these images to the
PACS prior to surgery to allow for presurgical planning by the
referring team. fMRI may provide the treating team with
information that could determine whether surgery is
feasible. For example, in a patient with a longstanding lesion
that causes seizures, determining language dominance
(which may be reorganized in younger children) may provide
a better estimation of the potential for language deficits
after surgery. In other cases, surgical approach may be
reviewed based on the location of eloquent functions
relative to the lesion.
Data analysis requires close attention to issues related
to data quality and coregistration, including assessing for
the presence of excessive movement. Although some tasks
obtained on the 3.0T scanner, particularly motor tasks, show
very robust results within a relatively short amount of time,
we choose to obtain two runs of each task in order to provide
some redundancy to ensure repeatable results. This, of
course, does not ensure that the patient consistently
and correctly followed directions, and the clinician should
interpret the results within the context of what is expected
from the task. However, two runs of each task helps to
reduce the interpretation of random activation. Other issues
to consider in clinical mapping, which may differ from
research applications, include the degree of smoothing and
the issue of false negative findings vs. false positives. These
issues do not differ based on the age of the patient, but may
be important considerations especially in children, who may
be more likely to have reorganized functions if their lesions
occurred during critical windows of brain development.
Summary
With the significant improvement in MR imaging, obtaining
high-quality functional and structural images for cognitively
impaired children can be done consistently and with a
minimal amount of distress to the patient. „
Figure 1. fMRI images show activation associated
with expressive (pink) and receptive (orange)
language in a right handed patient who had
resection of a tumor at age three. Patient shows
evidence of crossed language dominance with
expressive language in the predicted left frontal
lobe while receptive language (comprehension)
is solely in the right hemisphere. This bodes well
for language preservation if further resection
is required in this region (for seizures).
A GE Healthcare MR publication • Autumn 2009
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Discovery MR750 3.0T Elevates Clinical Utility of
High-Resolution Imaging of the Cranial Nerves
By Peter Lavery, Lead MR Radiographer and
Mitesh Ghandi, MD, neuroradiologist, Queensland X-ray
When a patient presents to a specialist with a nerve related
ailment, whether it be cranial or peripheral, high-resolution
imaging of the cranial nerves is used to help pinpoint and
diagnose conditions accurately and efficiently. The overwhelming response to MRI’s effectiveness in this area has
led to a surge in interest over the last few years.
At Queensland X-ray (QLD X-Ray), MR Neurography is
primarily used to investigate the cranial nerves. Clinical
literature describes MR Neurography as using T2-weighted
FSE sequences with ultra-long TEs, which depicts bright
abnormal nerves in a relatively dark background. The
technique produces high-resolution images of the cranial
nerves and their anatomical pathways by generating
extremely thin slices in multiple planes with multiple
contrast weightings. Historically, this led to lengthy scan
times, which often results in image artifacts and poor image
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SignaPULSE • Autumn 2009
quality due to patient movement, and, therefore, the
technique was not routinely used in clinical practice.
With the introduction of the Discovery MR750 3.0T from GE,
our radiologists and referring doctors can now successfully
apply this new frontier in neuroimaging. The Discovery
MR750 allows us to scan patients at a greater speed with
high resolution isotropic 3D sequences that can be reformatted
in multiple plans and variable slice thickness. Previously,
acquiring images in 3D caused a decrease in contrast,
compared to 2D, with variability in image quality when using
fat saturation techniques. However, a new technique on the
Discovery MR750 that couples a 3D FSPGR with IDEAL helps
overcome prior imaging limitations in MR Neurography. The
combination of improved speed and new technique now
enable our radiologists to view fine details of the cranial
nerves and small branches for a more accurate depiction
The information contained in this document is current as of publication of the magazine.
NEURO IMAGING
CLINICAL VALUE
of the extent of neuro pathology, such as perineural spread of skin cancers
along the cranial nerves and the detailed anatomical extent of tumors in the
skull base – the later two being the most common indications for the use of this
technique at QLD X-Ray. This accurate depiction of the tumor, its branches and
relationship to vital adjacent soft tissue structures in the skull base enables the
surgeon to more effectively tailor surgery to the individual patient.
Peter Lavery
Clinical case
Patient history
The patient was diagnosed with a pleomorphic adenoma in the right carotid, which
was surgically excised at age 13 followed by radiotherapy. In 2001, at age 47, he
presented to the specialist with loss of hearing and tingling in the right side of the
face. Clinical examination revealed a tumor in the right external auditory canal.
Further MR image reviews indicated a large tumor mass in the para pharynx
extending up through the jugular foramen, into the middle ear, and then into the
posterior cranial fossa. It completely surrounded the facial nerve and sat close to
the hypoglossal canal, extending towards the foramen magnum. Histology proved
the tumor to be a carcinoma ex pleomorphic (a malignant tumor that is believed
to develop from some benign pleomorphic adenomas after many years).
Peter Lavery, MRI radiographer at Queensland
X-ray and MRI supervisor at the Mater Private
Hospital, Brisbane, holds a Level 2 Accreditation
with the Australian Institute of Radiography.
He has supervised MR imaging departments in
London and Dublin, and is currently involved in
several research projects at the University of
Queensland while pursuing his Masters Degree,
including “Phosphorous Spectroscopy of the Calf
Muscle During Exercise” and “MRI of Adolescent
Idiopathic Scoliosis.” Lavery is a published author
on MRI imaging of scoliosis in The Radiographer,
an Australian peer-reviewed radiology journal.
The patient had near total removal of the tumor and a free-flap reconstruction
with post operative radiotherapy. In 2005, he had further recurrence of the tumor
in the jugular bulb and the lower aspect of the cerebellopontine angle. Biopsy
determined this to be a benign pleomorphic adenoma. At this stage the patient
had thrombosed his right internal carotid artery – possibly related to a combination
of radiotherapy and surgery.
Technique
Dr. Mitesh Ghandi
About the facility
The patient was scanned using the 8-channel HD Brain coil from GE Healthcare.
The acquired protocol consisted of a coronal T2 FS IDEAL and axial T1 and T2 FS
IDEAL sequence performed pre-contrast.
This was complemented by an axial 3D FSPGR IDEAL sequence, reconstructed
in three planes (1 mm/1 mm).
This sequence is described in Table 1.
Table 1. Axial IDEAL FSPGR + Contrast
Field of View (FOV)
180 mmw
Imaging matrix
256x256
Slice thickness
1 mm
Repetition time (TR)
6.7 ms
Echo time (TE)
Min TE
Frequency
A/P
Flip angle
12
NEX
1
Slice resolution
95%
Imaging options
ASSET (2); IDEAL; Zip 512; Zip 2; EDR
Scan time
3 min
The Mater Private site on the south bank
of Brisbane, Queensland, is the busiest of
approximately 40 radiology sites for Queensland
X-Ray. This multi-modality practice features the
most technologically advanced equipment in
Brisbane and includes 3.0T MRI, two multi-slice CT
scanners and a new PET CT facility. The facility’s
niche is in neuroimaging.
In March 2009, Queensland X-Ray installed
the first Discovery MR750 3.0T MRI system in
the Southern Hemisphere and continues to
explore the system’s potential, particularly in the
neurological field. Backed by some of the best
radiologists in Queensland, including Dr. Mitesh
Ghandi and Dr. Robert Clarke, and an enthusiastic
team of MRI radiographers, Queensland X-ray is
achieving incredible MR imaging results.
We are visualizing
nerves we’ve never
seen before.
Dr. Mitesh Ghandi
A GE Healthcare MR publication • Autumn 2009
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CLINICAL VALUE
NEURO IMAGING
Post Contrast – 3D IDEAL
Coronal Reformat – 3D IDEAL
Coronal Reformat – 3D IDEAL
Sagittal Reformat – 3D IDEAL
Sagittal Reformat – 3D IDEAL
Sagittal Reformat – 3D IDEAL
Diagnosis
Currently the patient has residual tumor in the jugular foramen, infiltrating the
hypoglossal canal and extending towards the clivus. This sits above and anterior
to his right vertebral artery. Given that he no longer has a right internal carotid
artery, his right hemisphere is predominately supplied by the right vertebral.
The case is currently with the interventional radiologist to consider whether it is
theoretically possible to sacrifice the vertebral should it be damaged in further
removal. The latest MRI suggests that the tumor has infiltrated the bony margins
of the jugular foramen bone indicating malignancy – Carcinoma ex pleomorphic
adenoma. „
MRA of the neck vessels. Data extracted from
the 3D IDEAL data set. Note the missing right
carotid vessel.
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The information contained in this document is current as of publication of the magazine.
IMAGE FUSION
CLINICAL VALUE
Easy-to-use MR Fusion
Software Helps Raise
Diagnostic Confidence
In most disease states, clinical diagnosis may require review of comprehensive
clinical data - anatomic, structural, or functional images as well as parametric
maps – acquired using diverse imaging modalities such as MR, CT, or PET. In
some cases, comparing current with prior patient exams may be necessary.
Image fusion is often used in neurology and oncology to analyze function
overlaid onto anatomic data, providing valuable information for identifying and
localizing lesions, and evaluating treatment success. Yet, until the release of the
Advantage Workstation® (AW) VolumeShare 4 (VS4) software from GE Healthcare,
reviewing several types of images simultaneously on the same screen, as well
as fusing MR with PET, CT, or other MR images, was a time-consuming process
for the radiologists at Laveran Hospital (Marseille, France).
According to Patrick Richez, MD, head of the department of radiology at H.I.A.
Laveran Hospital, cancer patients regularly receive whole-body diffusion MR
images after a TAP CT. Fusing the MR and CT images, however, was a challenge,
unlike other more automated software for fusing PET with CT.
“We first leveraged the fusion feature to compare MR diffusion with functional
images from a PET scan,” Dr. Richez explains. “Then, we started fusing ADC
cartography to STIR or T1 anatomical images. After that, we moved to neurology
to fuse diffusion with anatomic FLAIR, 3D, or perfusion.”
Dr. Richez realized the VS4 fusion capabilities has the potential to be applied to a
number of other clinical applications – the studies would just need to be validated.
He primarily uses fusion for whole-body and neurology imaging studies and,
to a lesser degree, hepatobiliary exams.
“What is most important to us is that this
software is simple and easy to use so we
can concentrate on diagnosis – and that
is best for the patient.”
Dr. Patrick Richez
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
CLINICAL VALUE
IMAGE FUSION
Diffusion
Fusion
Dr. Patrick Richez
Patrick Richez, MD, is head of the Department
of Radiology at the H.I.A. Laveran Hospital
and specializes in MSK and urology. He has
collaborated on numerous IRM evaluation
protocols with GE, particularly for muskuloskeletal
by leveraging CUBE & IDEAL sequences, and also
in whole-body imaging with Trevor La Folie, MD,
lead for oncological imaging at Laveran Hospital.
Fiesta/diffusion
Figure 1. Patient with recurrence of a cholesteatoma in the petrous apex
About the facility
The Laveran Hospital, built in 1963, is a
multispecialty military institution with 316 beds.
It bears the name of the army medical officer
Charles Louis Alphonse Laveran, who discovered
the parasite of paludism in 1880 in Algeria. The
MR system at Laveran was initially installed in
2001 by GE as a Signa® 1.5T MR and upgraded
to the Signa HDx platform in 2006.
“What really changed for us was the quality of interpretation and ability to view
the entire exam in our own way,” says Dr. Richez. On one screen, he can group
the complete set of views that were previously interpreted separately. “We can
configure the display for the complete encephalic study with all the sequences
that we acquired, including diffusion, contrast-enhanced 3D, and FLAIR. All
images are organized in one single screen and we can fuse the diffusion
sequence with FLAIR or 3D, for instance.”
The result is fusion imaging without additional steps, such as selecting the
exam to review. Without any doubt, the new VS4 fusion capabilities shorten
interpretation time for Laveran’s radiologists. Dr. Richez estimates he will benefit
from a 25% time savings for neurology and oncology explorations, and as much
Coronal STIR
Whole-Body DWI
Figure 2: VS4 generates CAD-like color fusion of STIR and DWI.
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IMAGE FUSION
CLINICAL VALUE
as 50% on whole-body reviews. “Once the exam is displayed, I have the entire
series accessible and fusing the images is a simple drag and drop. It is really
straightforward,” he says. For example, it takes just one click to complete the
function of autobind for diffusion imaging and match the study with sequences
acquired in axial or oblique views.
The new user interface for VS4 displays all MR contrasts, such as diffusion,
perfusion, and tractography, together in an intuitive manner. “The system
recognizes the sequences and displays the correct sequence in the right viewport
as it has been configured by the user,” comments Dr. Richez. He does, however,
caution that new radiologists might be overwhelmed by the amount of data
displayed. “You just need to know what information to use, and how to sort it.”
The true value is the increased diagnostic confidence. “These capabilities improve
the way we review, analyze, and report on all key areas of clinical interest,” says
Dr. Richez. “What is most important to us is that this software is simple and easy
to use so we can concentrate on diagnosis – and that is best for the patient.” „
Figure 3. Volumetry with Auto Contour
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
T E C H N I C A L I N N O VAT I O N
LOOKING FORWARD
Collaboration: The Science
of Working Together
GE Healthcare Thought Leadership Class 2009
For the third year, GE Healthcare has celebrated the
achievements of magnetic resonance (MR) innovators –
and its collaborations with these individuals.
“Our strong collaborator partnerships push us all to advance
in the MR industry,” explains Jim Davis, Vice President and
General Manager, GE Healthcare. “Collaboration is never an
end in itself, only a means. And it rarely happens by accident.”
This year’s class includes passionate, inspiring individuals
who demonstrate perseverance and commitment to
furthering the boundaries within MR.
These topics, while for research use only and not
commercially available, could be reality in years to come. „
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2009 MR THOUGHT LEADERS
T E C H N I C A L I N N O VAT I O N
Michael Lustig, PhD – Magnetic Resonance Systems Research Lab, Department
of Electrical Engineering, Stanford University. Dr. Lustig is best known for his
work in applying compressed sensing to MRI, a theory that enables vast
undersampling by exploiting the inherent sparsity and compressibility of MR
images. As part of a Stanford-GE collaboration team, GE’s Kevin King, PhD, is
investigating ways of incorporating compressed sensing into a variety of MRI
applications in GE products.
Krishna Nayak, PhD – Assistant Professor, University of Southern California. In
collaboration with GE scientist Ajit Shankaranarayanan, PhD, Dr. Nayak helped
implement the technique of wideband SSFP (a novel variant of the SSFP pulse
sequence, FIESTA) on commercial scanners, successfully applying it to the
imaging of cardiac ventricular function and coronary arteries at 3.0T.
Takayuki Masui, MD – Chief, Department of Radiology, Seirei Hamamatsu
General Hospital, Hamamatsu (Japan). In a recent collaboration with Naoyuki
Takei, a scientist at GE’s Applied Science Laboratory in Japan, he has helped
develop several non-contrast MRA techniques that have been applied to body
and peripheral vasculatures including the aorta, portal veins, renal arteries,
neck vessels, and lower and upper extremity arteries. This has yielded a
number of clinically applicable techniques and improved selectivity,
robustness, reproducibility, and simplicity.
Jeff Duyn, PhD – National Institutes of Health; Pratik Mukherjee, MD, PhD –
Associate Professor of Radiology and Bioengineering, University of California,
San Francisco. Powerful collaborations have helped expand the boundaries of 7T
imaging, finding the balance between high field strength and sensitivity. Dr. Doug
Kelly, senior scientist at GE Healthcare in San Francisco, has led collaborations
with Dr. Duyn and Dr. Mukherjee.
A GE Healthcare MR publication • Autumn 2009
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T E C H N I C A L I N N O VAT I O N
2009 MR THOUGHT LEADERS
John Kurhanewicz, PhD – Professor of Radiology, Urology and Pharmaceutical
Chemistry, University of California, San Francisco. Dr. Kurhanewicz and the
spectroscopy team at GE collaborated to develop PROSE, the first commercial
high spatial resolution anatomic and 3D metabolic imaging technique. PROSE
has helped improve the detection and characterization of cancer in prostate
cancer patients. Dr. Timo Schirmer, chief scientist and manager at GE Healthcare’s
MR Applied Science Laboratory in Europe, has taken a leadership role to
improve the accuracy of imaging prostate cancer.
Martin Graves – Consultant Clinical Specialist, Cambridge University Hospitals,
Cambridge (UK). Graves has worked for years in the field of interactive MR,
looking to expand the capabilities of real-time imaging into applications that
develop new paradigms for real-time scanner control. In close partnership with
GE scientists and engineers, such as Tom Foo, PhD, GE’s Global Research Center
Manager, Graves and his team plan to leverage the performance of next-generation
hardware to revolutionize interactive imaging.
Jingfei Ma, PhD – Department of Imaging Physics, University of Texas, MD
Anderson Cancer Center. Dr. Ma is credited with developing FLASE, GESFIDE,
FTED and MEDAL. His recent collaboration with Zac Slavens, signal & image
processing engineer at GE Healthcare in Waukesha, WI, has led to the
successful launch of MEDAL as LAVA-FLEX and VIBRANT-FLEX in the
GE Discovery platform.
(Alexander) Sandy Dick, MD – Scientist, Sunnybrook Health Sciences Centre,
Toronto (Ontario). Dr. Dick, along with Jeffrey Stainsby – manager of GE’s cardiac
and Interventional Applications – are pursuing uses of MRI in the context of
cardiac interventions. Through the development of novel multi-contrast late
enhancement imaging methods, they are working to improve the identification
and characterization of myocardial infarcts.
Garry Gold, MD – Associate Professor, Stanford University Department of
Radiology. Dr. Gold and Weitian Chen, PhD and scientist with GE’s Applied
Science Laboratory California, have been working on new methods for
three-dimensional ultra-short echo time imaging with the intention of
detecting early fibrocartilage degeneration in tendons and menisci. A
second project involves sodium imaging of articular cartilage in the
hope of developing new therapies to prevent post-traumatic arthritis.
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SignaPULSE • Autumn 2009
The information contained in this document is current as of publication of the magazine.
GE Healthcare
Introducing the Discovery™ MR750 3.0T.
Complex exams
without the complex.
Why do some MR exams have such a complex? Does the abdomen really need to pose
such a challenge? Wouldn’t fMRI be more functional if it were faster and more reliable?
We think MR should not only deliver clear, consistent images, it should do so quickly and
easily – even at 3.0T. Our new Discovery MR750 3.0T is designed to help you achieve
success with the most challenging exams. It can conduct complete liver exams in as little
as 15 minutes, and actually makes fMRI routine. Combined with a significant decrease in
in-room set-up compared with previous systems, the Discovery MR750 can give you a real
advantage – by giving tough exams less of a complex. MR Re-imagined.
To learn more, please call 866 281 7545 and reference MR08015
or visit www.gehealthcare.com/mr
© 2009 General Electric Company
The information contained in this document is current as of publication of the magazine.
T E C H N I C A L I N N O VAT I O N
MR AND DEMENTIA
Saving Future Memories
Search for faster diagnoses and better
treatment drives MR utilization
By Joanna Jobson, MR Global Marketing
Program Manager, GE Healthcare
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The information contained in this document is current as of publication of the magazine.
MR AND DEMENTIA
T E C H N I C A L I N N O VAT I O N
An estimated 35.6 million people worldwide will suffer
from dementia in 2010. Alzheimer’s disease (AD) is the
most common primary dementia with symptoms including
gradually deteriorating memory and/or progressing cognitive
function deficit. The prevalence is expected to double every
20 years1 as life expectancy continues to extend and one
of the largest demographic groups, baby boomers, near
retirement age.
There are no widely accepted “biomarkers” for the disease
and no robust universal baseline against which an individual
patient can be assessed. In general, people who are engaged
in higher level intellectual activities tend to notice symptoms
much earlier than those less intellectually agile. So the first
challenge in assessing relative change is to retrospectively
pinpoint the patient’s original baseline and compare it to
the current status.
In 2005, costs of direct and indirect care for AD patients
were $315 billion globally2 including 148 billion in the
United States alone.3
Treatment
Diagnosis
On average, accurate diagnosis of AD in patients takes
32 months in the United Kingdom, while Germany leads
with “only” 10 months.2 This disparity is likely due to the
highly subjective and variable diagnosis process, which
includes patient interviews and the use of cognitive and
memory tests, such as mini-mental state examination
(MMSE), that occur after other underlying diseases (such
as brain tumor, hydrocephalus or subdural haematoma)
are ruled out. Plus, dementia patients have a limited ability
to collaborate and frequently refuse to acknowledge any
related social or memory problems.
There is hope on the horizon. The high prevalence and
cost to society associated with the disease has helped draw
attention of policy makers and the scientific community,
leading to a massive effort that is driving clinical research.
Research aims to direct more objective, accurate, and faster
diagnosis followed by more efficacious disease-modifying
therapy agents to improve clinical outcomes and reduce costs.
These therapies should be effectively monitored to assess
effectiveness and minimize side effects. Considerable
research effort also focuses on prediction and prevention.
Images courtesy of LMU Munich, Germany
Patients with a number of other unrelated or comorbid
conditions might present with dementia.4 Worldwide, a
magnetic resonance imaging (MRI) scan of the brain is
accepted as standard procedure for ruling out other
organic conditions.2,4,5,6
While no effective treatment is available today, several drugs
such as Tacrine, Donepezil, Rivastigmine, or Galantamine
are currently being prescribed for dementia patients,
including use as combination therapies.7 These therapies
work by addressing neurotransmitter deficiencies and have
only a palliative effect while introducing risk of potentially
devastating side effects.
Figure 1. This BRAVO (IR SPGR) image offers
remarkable tissue contrast. Acquired as a 3D
isotropic volume, it can be reformatted to any
slice or plane without loss of resolution.
Figure 2. 3D ASL (510(k) pending) provides a
non-contrast enhanced perfusion assessment.
Figure 3. Microbleeds are easily detected and
well delineated on this SWAN image.
A GE Healthcare MR publication • Autumn 2009
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T E C H N I C A L I N N O VAT I O N
MR AND DEMENTIA
Current research indicates that MR imaging, molecular
neuroimaging with PET and cerebrospinal fluid analysis
will play a key role in the future clinical diagnosis process.4,5,6
The hope is that a more exact clinical exam can replace
current lengthy and objective patient evaluation.
There is also strong anticipation that in the next few years
new combination therapies will be available to stabilize,
modify and treat the disease. Multicenter studies and
initiatives driven by groups, such as the National Institutes
of Health’s (NIH) and Mayo Rochester Study of Aging offer
invaluable data repositories with comprehensive longitudinal
diagnostic data and samples on thousands of subjects,
including those who remain healthy as they age, others
who develop mild cognitive impairment (MCI), and in
some, progression to dementia.
The role MR can play
MR perfusion-weighted imaging (PWI) is another important
tool. Both 3D ASL (510(k) pending) and BrainSTAT offer techniques
to visualize and assess blood supply into the tissue.
These techniques can be aided by specialized T2*w imaging
such as SWAN to help visualize very small vasculature and
microbleeds that aid in diagnosis and help evaluate vascular
load (which can rule out subdural haematoma), and assess
iron or calcium deposits in the brain.
There is consistent evidence that hippocampal atrophy
is an early marker of dementia and that it correlates with
memory function impairment. Progressive significant
atrophy of the medial temporal lobes (MTL) that extends
to the entire cerebral cortex has been consistently reported
in patients with advanced dementia, and is associated with
the progression and extension of cognitive deficits.4,6,8,9
Images courtesy of J.B. Brewer, MD, PhD, UCSD
Image courtesy of UW Madison, WI
In 2007, the American Psychiatric Foundation modified
its practice guidelines to include, “The development of
additional imaging tools for improved diagnosis, early
recognition, and more precise assessment of disease
progression is a focus … these additional tools include
quantitative MRI, functional MRI …”.
Conventional neuro MRI will continue as the preferred tool to
rule out brain tumors, and other organic diseases as underlying
reasons for dementia-like symptoms.4,5 Three-dimensional
sequences such as BRAVO (T1w IR SPGR) and Cube enable
whole brain scans in high-resolution 3D with sub-mm
isotropic voxel in approximately three minutes. Techniques
such as PROPELLER that reduce motion artifacts can
also help acquire high-quality images even in
uncooperative patients.
Figure 5. Language activation map in green
(negative contrast in pink) overlaid on a highresolution 3D rendering of BRAVO. DTI fiber
tracking results are shown in orange.
Figure 4. Patient with fast progressing atrophy; colors mark bilateral hippocampal volume loss and
enlargement of ventricles over a period of 24 months.
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Image courtesy of Max-Planck-Institute of Psychiatry, Munich, Germany
MR AND DEMENTIA
T E C H N I C A L I N N O VAT I O N
robust turnkey fMRI suite that combines the flexibility
needed for research experiments and ease of use for clinical
routine. Since advanced dementia patients may not be able
to perform tasks, resting state fMRI can be considered as it
does not require patient cooperation, yet it can explore
functional brain connectivity.
An alternative method to evaluate changes in the white
matter associated with dementia is Diffusion Tensor Imaging
(DTI), combined with FiberTrak postprocessing, the package
provides advanced tools to acquire, visualize, and quantify
white matter trajectories.
Conclusion
Figure 6. This 68-year-old patient presented with dementia (MMSE = 8)
and was scanned for probable Alzheimer’s disease. An MRS exam of the
Parietal Cortex Spectrum shows significantly decreased NAA and increased
Myoinositol.
Clinical research also suggests that hippocampal atrophy
may help identify patients who are likely to progress
to dementia within a few years.4,5,6
Robust and fast automated brain segmentation and
morphometry tools, which can quantify changes in specific
brain structures are needed for broader adoption in clinical
practice. However, individual morphometry results should
be normalized based on the patient’s gender, age and brain
size to account for inherent variability within the patient
population.4,6,8,9 Measuring progression of gray and white
matter atrophy in certain brain structures may help assess
disease progression in a patient over time.
Dementia diagnosis and therapy monitoring are on the cusp
of radical medical breakthroughs, which could introduce
tools and procedures to allow new, faster, and more accurate
identification of afflicted patients and provide better, more
effective therapy that together can improve patient outcomes
and reduce costs.
The MR technology from GE Healthcare has been frequently
utilized in AD research since its inception in the early 1980’s.
Several new techniques, such as BRAVO, Cube, SWAN,
PROBE, and BrainWave provide a unique portfolio of
advanced tools for today’s research and tomorrow’s
clinical routine in the fight against dementia. „
Functional MRI (fMRI) has also been successfully utilized to
pinpoint the location of the eloquent cortex and to assess
memory and cognitive functions. BrainWave™ offers a
References:
1. World Alzheimer Report 2009. Alzheimer’s Disease International
2. Remember Those Who Cannot. Alzheimer Europe at European Parlament, Brussels
September 2007
3. Alzheimer’s Disease Facts and Figures 2007. Alzheimer’s Association
4. Albert M, et al. The Use Of MRI And PET For Clinical Diagnosis Of Dementia And Investigation Of
Cognitive Impairment: A Consensus Report. Alzheimer’s Association Neuroimaging Work Group
Consensus Report
5. Dubois B, et al. Research Criteria For The Diagnosis Of Alzheimer’s Disease:
Revising The NINCDS/ADRDA Criteria. The Lancet August 2007
6. Fayed N, et al. Utility of different MR modalities in Mild Cognitive Impairment and Its Use
as a Predictor of Conversion to Probable Dementia. Academic Radiology 2008
7. Kuljis RO. Advances in the Understanding of Pathophysiological Mechanisms in
Alzheimer Disease Applied to New Treatment Paradigms. Applied Neurology November 2007
8. Brain Imaging and Proteins in Spinal Fluid May Improve Alzheimer’s Prediction
and Diagnosis ICAD Press Release July 14th, 2009
9. Brewer JB. Fully-automated volumetric MRI with normative ranges: Translation
to clinical practices. Behavioural Neurology 2009; 21(1-8).
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
In recent years, non-contrast enhanced MR Angiography
(NCE-MRA) has gained interest in the clinical community
as an alternative to contrast-enhanced MRA, especially
in patients with renal insufficiency. Non-contrast run-off
angiography is particularly important due to the high
prevalence of peripheral vascular disease in patients
with renal insufficiency.1 However, non-contrast run-off
angiography can be challenging due to the close proximity
of arteries and veins, and relatively slower flow compared
to renal and cerebral arteries.
Inhance DeltaFlow is a new addition to GE Healthcare’s
Inhance family of robust, anatomy-optimized NCE-MRA
sequences. It is based on cardiac-gated 3D fast spin echo
that leverages the arterial flow difference between systole
and diastole to provide excellent visualization of peripheral
arteries with good suppression of veins and background tissue.
Hold the Contrast, See the Flow:
3D NCE-MRA of the Peripheral Vasculature
By Raman Subramanian, MR Applications Development Engineer, GE Healthcare
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The information contained in this document is current as of publication of the magazine.
ANGIOGRAPHY
Figure 1: Systolic image
Figure 2: Diastolic image
This technique acquires two images – one during systole and
one during diastole. The acquired systole image is nearly
free of arterial signal since fast flowing arteries dephase
quickly (Figure 1), while the acquired diastole image depicts
the arteries as bright signal due to slower arterial flow
(Figure 2). Unlike the arteries, veins and background tissue
signal are relatively independent of the cardiac phases. A
subtraction of the systole image from the diastole image
results in excellent depiction of the peripheral arteries with
good suppression of veins and background tissue (Figure 3).
T E C H N I C A L I N N O VAT I O N
Figure 3: Subtracted image
Inhance DeltaFlow is an excellent MRA technique to visualize
peripheral arterial flow that generates signal-rich 3D images
with conspicuous contrast, excellent venous and surrounding
tissue suppression, in a clinically feasible scan time. „
Protocol
3D
Coronal (or oblique coronal)
Matrix: 320x224
Receiver bandwidth: 62.5 kHz
FOV: 40 cm
Clinical benefits
TE: 35 to 90 ms
Inhance DeltaFlow provides improved visualization of slow
flowing arteries and reduced scan time compared to a
conventional gated 2D time of flight (TOF). Since Inhance
DeltaFlow is a 3D technique, it generates an inherently
higher signal-to-noise ratio (SNR) than 2D techniques. Plus,
3D acquisitions can be performed in the coronal plane,
which considerably shortens scan time vs. the axial 2D
TOF technique. Additionally, source images acquired in
the diastole can be used to validate slow flowing arteries.
Some of the technical challenges, such as mistiming of
the acquisitions due to cardiac rate changes and anatomy
misregistration on the subtracted images (due to potential
patient movement between each cardiac phase acquisition),
are minimized by improved acquisition strategies. Finally,
Inhance DeltaFlow can provide better visualization of all
arteries in both in-plane and through-plane blood flow
direction as compared to 2D TOF techniques.
Figure 4 demonstrates the feasibility of this technique
with a three-station acquisition on an Optima MR450 1.5T
system (GE Healthcare) using the body coil in a total scan
time of approximately 13 minutes. ASSET parallel imaging
technique is also supported when using a surface coil.
PG or ECG gated
STIR
TR: 3 R-R
Slice thickness: 2.2 to 3.0 mm
Slices: 36 to 48
Scan time: ~4 min per station
Figure 4
Reference:
1. O’Hare AM, Glidden DV, Fox CS, Hsu CY: High prevalence of peripheral arterial disease in persons
with renal insufficiency: Results from the National Health and Nutrition Examination Survey
1999–2000. Circulation 109: 320–323, 2004
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
T E C H N I C A L I N N O VAT I O N
OPTIMA MR450W INTRODUCTION
The First Wide-Bore MR System
From GE Healthcare Is Here
And it’s about so much more than the bore
By Jim Davis, Vice President and General Manager of MR, GE Healthcare
You have been asking us for a magnetic resonance (MR) system with a wider bore,
but without the traditional limitations – mainly compromised image quality –
that were often associated with 70-centimeter scanners. You’ve been waiting
patiently, and we appreciate the support, interest, and collaboration along the
way. We’ve been working on something special… something that’s about more
than just the bore diameter. Quite frankly, it has taken a while because we are
passionate about getting it right – and we feel strongly that we’ve done just that.
The wait is over, and we are thrilled to announce that the Optima MR450w, offering
exquisite image quality, simplified workflow and an uncompromised 50-centimeter
field of view (FOV), is now available. We feel it’s truly “wide-bore MR done right.”
The workhorse system
The Optima MR450w allows you to more efficiently serve a wider range of patients.
I think you will agree that we’ve overcome the limitations of 70-centimeter MR
by delivering both uncompromised image quality and patient comfort.
But it’s about much more than just the 70-centimeter bore. The Optima MR450w
offers a range of new advanced functionality, making it a workhorse system for
practices of all sizes and specialties.
According to A. Joseph Borelli, Jr., MD, president and medical director of MRI
at Belfair in Bluffton, SC, GE has overcome all of the limitations that he has
seen with 70-centimeter MR. He notes that as radiologists, administrators, and
technologists continue to demand productivity without compromising image
quality, the Optima MR450w is uniquely positioned to offer applications and
capabilities aimed to drive efficiency, improve usability, and reinforce growth.
It is also one of the most accessible MR systems available. Its cost and capabilities
make it ideal for first-time MR customers who can make it their only scanner,
as well as established MR users seeking a versatile, hard-working system. The
system’s 1.5T field strength is the industry’s best known and most used. And, its
bore diameter and FOV make MR scans accessible to more patients who need
them. The Optima MR450w can help you deliver solid financial returns, maintain
a high level of patient safety, and increase the quality of patient care.
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The information contained in this document is current as of publication of the magazine.
OPTIMA MR450W INTRODUCTION
T E C H N I C A L I N N O VAT I O N
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
T E C H N I C A L I N N O VAT I O N
OPTIMA MR450W INTRODUCTION
Comfortable for a football player
As you very well know, patient expectations of MR have
shifted in recent years, as people have begun demanding a
better, more comfortable scanning experience. The Optima
MR450w offers just that, which in turn affords clinicians the
comfort of a confident diagnosis.
access to an open MR scanner, due to his severe
claustrophobia. Butler feels that this new system from
GE Healthcare brings advanced applications, high quality
imaging, and comfort to patients like him who have
a fear of being closed in.
The new system increases accessibility for claustrophobic
and obese patients – without sacrificing high-resolution
imaging, patient comfort, or clinical productivity. For example,
LeRoy Butler, a former football player with the Green Bay
Packers, recognizes the value of the Optima MR450w.
Throughout his career, he had to drive several hours for
With a 50-centimeter FOV, Optima MR450w enables users to
scan more anatomy with fewer scans compared to previousgeneration systems. According to the Centers for Disease
Control and Prevention, nearly one-third of adults and 16%
of children are obese in the United States – leading to higher
incidences of cardiovascular disease, Type 2 diabetes, stroke,
and cancer.
Two-station whole spine
VIBRANT-Flex Water Only
VIBRANT-Flex Fat Only
IDEAL In-phase
VIBRANT-Flex In-Phase
VIBRANT-Flex Out-of-Phase
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SignaPULSE • Autumn 2009
IDEAL Water Only
The information contained in this document is current as of publication of the magazine.
OPTIMA MR450W INTRODUCTION
3D Merge
Cervical DTI
FSE Fat Sat
Inhance Inflow IR
T E C H N I C A L I N N O VAT I O N
The first order
Chris Fitzpatrick, global MR product marketing manager
for GE Healthcare, notes that as obesity reaches epidemic
proportions worldwide, it is important that this patient
population has the same access to high-quality MR imaging
as patients with normal weight so that clinicians can detect,
monitor, and treat obesity-related diseases. Built on a fully
redesigned MR platform, the Optima MR450w offers
applications and capabilities that improve usability while
GE Healthcare’s eXtreme gradients yield scans that are
fast, accurate, and highly reproducible.
In addition to the new gradients, the Optima MR450w features:
• A new 145-centimeter long magnet with excellent
homogeneity;
• A GE-exclusive optical RF chain that increases the SNR
of the system;
• Anatomy-optimized RF coils to provide external coverage
where needed for optimal image quality in virtually every
procedure; and
• A detachable express patient table, exclusive to
GE Healthcare, which minimizes time between scans
and helps boost productivity.
Ochsner Health System in New Orleans placed the first
order for the new system. According to Warner Thomas,
Chief Operating Officer, Ochsner has been a large supporter
of GE Healthcare pursuing this new “wide bore” MRI scanner.
Once the Optima MR450w was released and Ochsner
realized its uncompromised image quality, advanced
applications, and patient comfort, it sealed the medical
center’s interest. The hospital wanted the earliest possible
access to the new system so it could equip its world-class
physicians with the very best diagnostic tools and technology
available. Ochsner is thrilled to be the first to offer this new
level of MRI scanning to its patients.
Ochsner anticipates that the scanner will be installed at
Ochsner North Shore by the end of the first quarter in 2010.
Dr. Joseph Hajjar, Ochsner North Shore Radiology Chairman,
says that GE’s advanced applications on the newest
wide-bore platform in the industry will be a great addition
to the organization’s “Super Clinic” in Covington, LA.
We feel that the Optima MR450w is the right MR system in so
many ways. It offers the right capabilities, the right experience,
and the right investment. We hope you will agree. „
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
BEYOND THE SCAN
SERVICES
Maintain High-Quality Imaging,
Control Service Costs
With AssurePoint Services
New range of packages provides flexible, tailored service contracts
In today’s demanding healthcare environment,
maintaining high performance, uptime, and throughput
in the magnetic resonance (MR) suite is more critical
than ever. Reimbursement pressures make it
essential that providers optimize equipment
utilization by avoiding delays due to downtime
or performance issues. To protect and advance their
position in highly competitive markets, providers
need the assurance of consistently high image
quality across a range of exams. In addition,
providers need to control service costs
as effectively as possible and work within
budgetary constraints.
To help MR service customers overcome
these challenges, GE Healthcare has
created the AssurePoint™ Services
portfolio. This new portfolio of service
offerings can more effectively meet
the needs of MR imaging
providers by providing flexible
service solutions tailored
to their needs.
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The information contained in this document is current as of publication of the magazine.
SERVICES
BEYOND THE SCAN
“Our MR field team has
extensive knowledge and
is equipped with the latest
diagnostic and service tools.”
Michael Giesecke
“We’ve created a range of packages to give customers
greater flexibility in how their service contracts are
structured,” says Michael Giesecke, GE Healthcare MR
Services Marketing Leader. “This enables customers
to select the service features that are most important
to them and avoid paying for features they don’t want
or need.”
For example, the AssurePoint Rapid program brings
together services focused on reducing downtime, such
as proactive digital service technologies that identify
emerging service issues and repair them during
a scheduled service event in order to avoid unplanned
downtime and disruptions to patient care.
The AssurePoint Services family of service offerings includes
four service packages of particular interest to MR providers:
• AssurePoint Standard helps providers reduce
unplanned downtime and maintain their MR
equipment with programs that deliver results
and value;
• AssurePoint Rapid helps providers
keep patient care and workflow on
track with responsive service and
proactive monitoring to optimize
MR uptime and productivity;
• AssurePoint Performance helps providers optimize
asset efficiency and utilization through service metrics,
performance informatics, service documentation tools,
and applications training; and
• AssurePoint In-House gives providers the option of tapping
into GE Healthcare resources and experience
to complement their in-house service capabilities.
These new offerings also leverage the experience
of the GE Healthcare MR service engineers. “Our MR field
team has extensive knowledge and is equipped with the
latest diagnostic and service tools,” says Giesecke. “Plus,
we deploy more service engineers per square mile across
the United States than any other service provider to make
sure help arrives quickly when customers need us.”
AssurePoint Services is also an integral part of GE Healthcare’s
ongoing commitment to MR customers. “When customers
invest in MR, they expect their technology to remain clinically
viable for a very long time,” says Giesecke. “AssurePoint
is an example of GE Healthcare’s continuing investment
in resources and technology to help its MR customers
get the most from their equipment investment.” „
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
BEYOND THE SCAN
PAT I E N T S A F E T Y
Turning Up the Heat
on Patient Safety.
Turning it Down
to Prevent Burning.
Keeping patients safe
and comfortable during
magnetic resonance (MR)
scans is a priority for
operators. Unfortunately,
during routine scans,
patients can get
excessively warm
and even burned
if precautions are
not taken. Let’s take
a step back to MR 101
to review why heat
is a potential hazard.
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The information contained in this document is current as of publication of the magazine.
PAT I E N T S A F E T Y
BEYOND THE SCAN
Heat: what’s the harm?
Tips for cooling the heat
Systems capable of MR imaging use resonant radiofrequency (RF) magnetic fields to excite certain nuclei, usually
protons. Heating is the potential safety concern, as some
portion of the transmitted RF energy might be absorbed
by the patient. Tissue heating can occur if the RF pulses
are delivered faster than the patient’s tissues can dissipate
the generated heat.
Here are some easy-to-perform tips, which can be found
in the GE Healthcare Safety Guide, for avoiding an overdose
of heat:
“It is essential for patient safety to limit whole-body and
localized heating to appropriate levels,” says Joe Schaefer,
principal safety engineer for MR at GE Healthcare and
member of the American College of Radiology’s Blue Ribbon
Panel on MR Safety. “MR has a very safe reputation, and
in the vast majority of cases, scans are performed without
incident. However, elevation of core body temperatures
to sufficiently high levels may be life threatening,
so it’s important that this hazard be taken seriously.”
Schaefer points out that the limits in the international MR
safety standard (IEC 60601-2-33) are designed to ensure
safety. In addition, the standard calls for scan operators
to carefully screen and monitor patients.
Plus, it’s crucial to address heating in your MR Safety Program.
Taking a systemic approach to MR safety and establishing
a culture of awareness and responsibility at all levels of
your organization can help minimize the likelihood of MR
accidents. When documenting and training policies and
procedures, it’s important to include common hazards – how
to prevent them, and if necessary, how to address them.
• Be sure the magnet room is set at less than 70°F.
Operators oftentimes mistakenly think that a warmer
room means a more comfortable patient.
• Remember that RF can cause localized heating at contact
points between the patient/bore, the patient/RF coil and
adjacent body parts when a loop is formed (for example,
when a patient’s hands are touching) – resulting in
discomfort or burns. To prevent this:
– Place non-conductive padding at least 0.25 inches thick
between the patient and the bore wherever a portion
of the body may come into contact with the bore wall.
– Place at least 0.25 inches thick padding between
the surface coil and the patient’s skin.
– Use pads at least 0.25 inches thick between body parts
to avoid creating a loop with adjacent body parts.
Padding also keeps body parts in the correct position –
away from a possible burning incident. Proper padding
is a simple way to prevent burns, but it’s frequently ignored.
Don’t get complacent about this very important step.
• For shoulder imaging, place padding between the
patient’s opposite shoulder and the bore, or wherever
the patient’s body comes into contact with the bore.
A GE Healthcare MR publication • Autumn 2009
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The information contained in this document is current as of publication of the magazine.
BEYOND THE SCAN
PAT I E N T S A F E T Y
• Don’t lay blankets on patients – this is well intentioned
but can easily overheat them.
• Turn the bore fan on – and keep it on – to maintain air
flow inside the bore. Many operators forget to do this.
Also, ensure that air flow through the bore is unobstructed.
• Take care to enter the patient’s weight correctly, as the
system’s estimate and adjustment of the heating level
is based in part on patient weight.
• A sensor in the bore monitors temperature and posts
messages in the System Status Display that notify you
when the magnet bore wall is becoming warm. Pay
attention to this and watch for overheating.
• Be thorough with pre-screening, as conditions such as
hypertension, diabetes, old age, obesity, or an impaired
ability to perspire may reduce thermoregulatory capacity
(the ability of the body to maintain a fixed core temperature).
Elevated body temperatures may be a concern for such
patients, who should be carefully monitored at all
times. Operation in the lower SAR NORMAL MODE
may be considered.
• The following can cause RF heating – be sure to check
before the scan begins: the formation of loops with
RF receive coil tables and ECG leads; the use of non MRcompatible ECG electrodes (never use ECG electrodes past
their expiration date); and scanning with an unconnected
receive coil or other cables in the RF transmit coil during
the examination.
• Pay extra attention to patients who are unconscious
or sedated, or may have loss of feeling in any body part,
as they may not be able to alert you to RF heating.
• Make sure the coil selected matches the coil that is
connected. When scanning with a transmit/receive only
coil, DO NOT scan using the body coil (or using the body
coil configuration), because it can cause RF heating
and could result in patient burns.
According to David Goldhaber, systems architect in MR at
GE Healthcare, metallic heating is another potential hazard
related to the RF field. The heating of implants, devices, and
objects made of metal might cause temperature changes
during an MR examination. The induced currents in the
metallic objects may cause them to get so hot they can
actually cause burns in adjacent tissues.
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SignaPULSE • Autumn 2009
“It’s really important to determine each patient’s work history
and thoroughly screen for any accessories containing
metal,” explains Goldhaber.
Observe the following warnings concerning metallic heating
to protect patients from excessive heating or burns:
• Eye makeup that contains metal flakes can cause eye and
skin irritation during MR scanning. Ask patients to wash
makeup off before the exam. Patients with permanent
eyeliner or metallic ink tattoos should be warned about
the risk of skin irritation.
• Metal fragments/slivers can deflect and/or heat in a
magnetic field, damaging surrounding tissues. Patients
thought to have metallic fragments in the eye should
receive an eye exam to detect and remove any
metal fragments.
• Jewelry, even 14-carat gold, can heat and cause burns.
Ask patients to remove all jewelry.
• Medicinal products in transdermal patches may cause
burns to underlying skin. Discuss this with the patient.
If a burning incident does occur, guide the patient to
treatment and report the situation to GE Healthcare.
Prevention is key
“When it comes to heating accidents, a pinch of prevention
is worth a pound of cure,” suggests Schaefer. “Updating and
continuous training of your MR Safety Program will help you
keep prevention and safety in mind.”
The goal of an MR Safety Program is to prevent risks and
harm to patients and healthcare professionals. However, an
MR facility can’t adopt only a couple interventions and hope
to be successful. Integrate and train these tips and your
facility will be on its way to a safer environment.
Look for articles about additional safety risks and how
to avoid them in upcoming issues of SignaPULSE.
For more information visit www.gehealthcare.com/usen/
mr/mrsafety/index.html. „
The information contained in this document is current as of publication of the magazine.
MR: Making a Difference
Through healthymagination
A GE Healthcare MR publication • Autumn 2009
75
The information contained in this document is current as of publication of the magazine.
BEYOND THE SCAN
H E A LT H Y M A G I N A T I O N
People in many parts of the world are extremely excited about
GE’s healthymagination, which represents the commitment
to deliver product and services that allow physicians to deliver
better care to more people at a lower cost.
By Michael Barber
Vice President, healthymagination, GE Healthcare
Addressing industry challenges
More than 100 innovations targeted
Announced in spring of 2009, healthymagination has been
launched to address an industry challenged by rising costs,
inequality of access, and persistent quality issues. The aim
of the initiative, which includes a $6 billion commitment
from GE through 2015, is to innovate smarter processes
and technologies that help physicians and hospitals
throughout the world provide a higher level of healthcare
to more people – and save costs in the process.
healthymagination is rooted in research and development.
As part of the new approach to healthcare, GE will launch
at least 100 innovations that lower cost, increase access,
and improve quality. By 2015, the total investment
in R&D will amount to $3 billion in new and innovative
healthymagination products.
healthymagination also takes its cue from GE’s successful
ecomagination environmental initiative, which has shown
that technical innovation can drive solutions and value
for GE customers and the people they serve. Additionally,
ecomagination dovetails with healthymagination because
things like clean air and water contribute to the ultimate
goal: to help people live healthier lives.
As with ecomagination, the success of healthymagination
hinges on the ability to deliver the right solutions. In the
healthcare industry that means technologies that improve
quality and at the same time lower costs, products that
match specific local needs, and process expertise to help
healthcare providers win.
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SignaPULSE • Autumn 2009
The total R&D investment means that the majority
of GE Healthcare’s spending is on innovations that:
• Reduce by 15% the costs of procedures and process
that utilize GE technologies and services.
• Increase by 15% people’s access to services and
technologies, which are essential for health – reaching
100 million more people every year.
• Improve quality and efficiency by 15% for customers
though simplifying and refining healthcare procedures
and standard of care.
In addition to GE Healthcare’s $3 billion spend, GE Capital
will provide $2 billion in financing for advanced healthcare
IT and several GE businesses will spend another $1 billion
The information contained in this document is current as of publication of the magazine.
H E A LT H Y M A G I N A T I O N
on partnerships, media, and services related to
healthymagination. GE has also contracted with a highly
reputable third-party firm to monitor progress and validate
the initiative’s success.
healthymagination is truly a commitment that is unparalleled
in healthcare, and with good reason: Innovation plays
a critical role in the ability to deliver better care to more
people at lower cost.
While all GE Healthcare products and services are in the
spirit of healthymagination, only those products that pass
a rigorous third-party assessment will carry the title of
healthymagination verified. Simply put, they must provide
third party evidence of reducing cost, increasing access, and
heightening quality for healthcare providers and patients.
The vital role of MR
Vital to healthymagination are breakthroughs in magnetic
resonance since the initiative includes early detection
and prevention of disease. In MRI, the path toward costs
savings, increased access, and improved quality is well
defined with a broad range of innovations and initiatives
already in place, or soon to be announced.
BEYOND THE SCAN
Clear examples are MR-Touch, which offers a visual,
non-invasive means to determine the liver’s stiffness
or the Brivo MR355*, a 1.5T system that enables easy,
accessible MR technology to physicians who may
not have had access in the past.
Both technologies offer physicians new means to greater
patient care and access to additional information for a
more complete, confident diagnosis.
It all ties together
The list of innovations is long. It’s also a list that will continue
to grow as healthymagination takes hold. Yet each and
every innovation – and each and every service – only sees
the light of day if it helps to lower cost, increase access,
and improve quality. In the end, it’s about the ability to:
• accurately detect disease early on so that hospitals
can save costs and patients can live longer, fuller lives;
• dramatically reduce the need for additional scans
or costly procedures to save costs and make life more
comfortable for patients, especially those who visit
hospitals regularly;
• achieve the lowest possible dose without sacrificing
the quality of images so clinicians and physicians
can get the whole story;
• treat more patients in less time so that imaging
technologies are maximized;
• provide the wonders of diagnostic imaging to areas
of the world where it can greatly improve the quality
of life; and
• successfully overcome the challenges that get
in the way of delivering quality healthcare.
healthymagination, together with ecomagination, is about
making a difference in the health and welfare of human
beings everywhere. It’s also about dedicating the necessary
resources and working together with any number of partners
to get it done. It all ties together. „
*510(k) pending.
A GE Healthcare MR publication • Autumn 2009
77
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Uncut
To receive future issues of
SignaPULSE, please subscribe at:
www.gehealthcare.com/signapulse
At GE, we believe what’s needed, right now, is a new mindset:
that health is everything.
We call it healthymagination
Just as we delivered innovation in environmental technology with ecomagination,
healthymagination will change the way we approach healthcare, with over
100 innovations all focused on addressing three critical needs: lowering costs,
touching more people, and improving quality.
Reduce Costs
Increase Access
Improve Quality
By 2015, our goal is to reduce by 15%
the costs of many procedures and
processes with GE technologies and
services.
By 2015, our goal is to increase by 15%
people’s access to services and technologies essential for health, reaching
100 million people every year.
By 2015, our goal is to improve quality
and efficiency by 15% for customers
by simplifying and refining healthcare
procedures and standards of care.
© 2009 General Electric Company
MR-0388-11.09-EN-US