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In Practice
Breast MR in
Less than Ten Minutes
Development of a rapid breast MR protocol
The American Cancer Society and other
“MR is the most sensitive imaging tool
However, a significant clinical challenge
committee guidelines recommend
we have at our facility for our high-risk
with breast MR is the length of the exam.
that women with a 20% or greater
breast cancer patients,” says Constance
Historically, a typical breast MR exam
lifetime risk of breast cancer consider
Lehman, MD, PhD, FACR, Director of
can last up to 45 minutes. Dr. Lehman
MR screening as a supplement to
Breast Imaging and Co-director of
adds that, in general, some women may
mammography, in order to have breast
AVON Breast Center, Massachusetts
not have access to breast MR, as not all
cancer detected at an earlier stage and
General Hospital (MGH). “At our
hospitals or clinics with an MR scanner
when still node negative. In addition,
hospital, MR imaging can double our
provide this type of imaging service.
for women diagnosed with a newly
cancer detection rate and cut in half
diagnosed breast cancer, MR provides
node positive disease by helping us
more accurate information regarding
image the disease earlier, when we
the true extent of disease, both within
have the best chance to treat it.”
the breast with the known cancer as
Seeking a solution that would reduce the
time of an MR breast imaging exam, Dr.
Lehman reached out to GE Healthcare’s
Ersin Bayram, Body/Vascular MR
Applications Manager, and Arnaud Guidon,
well as in the opposite breast.1
Body/Vascular MR Development
Scientist, to help develop a rapid
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Constance Lehman, MD,
PhD, FACR,
breast MR imaging protocol that
VIBRANT volume acquisitions, we had
would retain the high quality and high
such high spatial resolution with the
diagnostic confidence of the traditional
Axial that we could reconstruct the
MR breast protocol and fulfill the
Sagittal images. That would replace the
American College of Radiology’s (ACR’s)
need to acquire those Sagittal images
requirements for an accredited exam.
at a later time point in the exam.”
“We recognized that we have stronger
Increasing patient access
and clinical confidence
“At MGH, we went from a 45-minute
exam to a 9-minute, 48-second exam
without losing the key components
that the ACR requires for an accredited
The high spatial resolution of the acquired
exam,” says Dr. Lehman. “This really
magnets, faster methods to acquire the
volumetric Axial VIBRANT images can
changes the whole process for us and
images, and better coils,” Dr. Lehman
also be used for coronal reconstructions
how our patients will think about breast
explains. “Could we take those
and 3D MIPs, Dr. Lehman adds.
MR. It is my strong belief that here at
improvements in technology and
actually deliver a higher-quality product
to our patients?”
While some sequences were removed
altogether, others were reduced in time
without sacrificing quality by utilizing
MGH, we may have the same quality
in a shorter scan at a lower cost for
us—and that may translate into a better
patient experience.”
Dr. Lehman worked with Bayram
the strength of a 3.0T magnet and
and Guidon to transition the breast
16-channel coil. For example, dynamic
For a woman who may need medication
MR protocol from a 1.5T, 8-channel
and non-FatSat SPGR sequences
to undergo a 45-minute breast exam,
coil protocol to a 3.0T, 16-channel
moved to higher resolution VIBRANT
she may now be able to tolerate the
coil protocol.
with 0.8 mm voxels, which was made
scan without it. Additionally, in the
possible with the 16-channel breast
past it would be difficult to add another
A typical breast protocol on a 1.5T scanner
with an 8-channel coil is comprised
of six pulse sequences: a pre-contrast
Axial 3D SPGR, Fast STIR inversion
recovery, a pre-contrast Sagittal
VIBRANT, an Axial multi-phase VIBRANT,
and a post-contrast Sagittal VIBRANT.
3
coil with an acceleration factor of 6. The
45-minute breast MR exam in MGH’s
ACR requires a bright fluid sequence
busy schedule; however, with the
for an accredited exam. The team was
shortened protocol there may now be
able to shift this 2D sequence to a Cube-
room to open up access to breast MR
based volumetric scan that increased
for more women.
slice resolution drastically to 0.8 mm
slices and in the process reduced
One of the key areas where the team saw
scan time from 5 to 2 minutes with
an opportunity to reduce the number of
acceleration of 6 and still generated
sequences without sacrificing quality
a high-quality scan.
was in the Sagittal acquisitions.
The result is a rapid breast MR protocol
“Many breast imaging facilities acquire
that incorporates a Cube T2, non-fat
Axial images and then later they also
suppressed VIBRANT T1, and a dynamic
acquire high spatial resolution Sagittal
VIBRANT fat suppressed T1 series
images,” Dr. Lehman explains. “What
consisting of a pre, initial and delayed
we found was that with Cube and
post-contrast with a fat suppressed
T1 image.
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“In our facility, we’ve tripled access to
breast MR—it’s the right thing for our
patients and hospital,” Dr. Lehman adds.
She also believes that a shorter breast
MR can positively impact the radiology
department at MGH. Dr. Lehman
explains, “There was a lot of information
we were collecting that we weren’t
using to increase our diagnostic accuracy.
This really helps focus our radiologist’s
attention on the scans that may
increase their diagnostic confidence.
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In Practice
Director of Breast Imaging and Co-director
of AVON Breast Center, Massachusetts
General Hospital (MGH) in Boston, MA.
Where we started:
GE SIGNA™ HDx 1.5T breast protocol, 8-channel, total scan time 40-45 minutes, 4 mm thick T2 and 2 mm thick T1 VIBRANT
Series #
Pulse Seq.
1
GradientEcho
2
GradientEcho
3
SPGR
4
IR
5
VIBRANT
6
VIBRANT
7
VIBRANT
TE
TR
In-phase
Flip Angle
10
60
6600
In-phase
In-phase
FOV
Thick
Skip
NEX
Freq Dir.
Phase
Encode
Freq
Encode
32
7
2
2
Unswap
128
256
48
15
0
32
3
2
A/P
256
384
35
4
2
A/P
192
320
10
20
3
10
32
2
10
20
3
A/P
0
1
1
A/P
384
384
A/P
384
384
A/P
384
384
New rapid breast MR protocol:
3.0T magnet with bilateral 16-channel dedicated open breast coil, total acquisition time 9 minutes, 48 seconds
Series #
Pulse Seq.
FOV
Matrix
Resolution
Slice
NEX
Phase
Non FS
T1
VIBRANT
320
400/400
0.8 x 0.8 x 0.8
0.8
1
A/P
1:19
5/2.3
T2
FS
Cube T2
320
352/352
0.9 x 0.9 x 0.8
0.8
1
A/P
1:54
2500/90
Dynamic
T1
FS (3)
VIBRANT
320
400/400
0.8 x 0.8 x 0.8
0.8
1
A/P
2:04
6.4/2.4
Localizer
Time
TR/TE
20 sec
“Plus, with the shorter scan time, I have
seen that there is less patient motion
which leads to fewer motion artifacts—
another benefit that impacts diagnostic
quality and clinical confidence.”
(interpolated – 1.6
thick overlapping)
Beyond diagnosis
The rapid breast MR protocol has
implications for enhancing patient
care at MGH. Dr. Lehman points out
that in the US, there are approximately
per phase
(1 pre, 2 post)
Dr. Lehman shares the story of a patient
undergoing neoadjuvant therapy for
an aggressive tumor. The patient could
not finish the 45-minute breast exam
at another facility—she had difficulty
with an MR exam in general. Ultrasound
Although the rapid breast MR protocol
1.6 million breast biopsies performed
was originally implemented on the
each year, of which 30% are surgical.2
facility’s 3.0T MR scanner, Dr. Lehman
Each year, 300,000 women have
and her team are working with GE
unnecessary surgical breast biopsies. It
Healthcare to implement it on 1.5T
may be possible that MR could provide
scanners. And she’s not done modifying
an alternative to surgical biopsy to help
So, Dr. Lehman talked to the lead MR
the protocol—Dr. Lehman is confident
reduce excision of benign biopsies or
technologist and explained that the
was suggested, however, it was the
wrong imaging study for the patient
presentation—what she really needed
was an MR exam.
that they can add more diagnostic
provide the images needed to help guide
woman was seeing her surgeon that
information by including diffusion
other minimally invasive techniques.
day. The surgeon couldn’t tell if the
imaging and still maintain a rapid
breast MR scan in under 10 min.
Breast MR images may be utilized by
clinicians to help visualize changes in
soft tissues that could be the result
of treatment.
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tumor was responding or not, and the
information from an MR exam would
possibly make a difference in planning
the next steps in treatment.
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In Practice
A
C
Figure 1. The rapid breast imaging protocol at MGH incorporates a (A) Cube T2
fat suppressed, and a dynamic VIBRANT fat suppressed T1 series consisting of
a (B) pre, initial and (C) delayed post-contrast with a fat suppressed T1 image.
A
B
Figure 2. Isotropic voxel imaging with VIBRANT enables high-resolution multiplanar
reconstruction in any direction without loss of spatial resolution and in a scan
time of 2:04 min per acquisition. Shown here are (A) Sagittal post-contrast and
(B) maximum intensity projection reformat
“The technologist said to send her over,
The impact at MGH has been significant,
References
they could fit her in between patients,”
from advancing patient care to
Dr. Lehman says. “With a less than
implementing change management.
10-minute exam, we can do that; with
Dr. Lehman says that it is important, as
1. American College of Radiology. Diagnostic Radiology:
Magnetic Resonance Imaging (MRI) Practice Parameters
and Technical Standards. Available at: http://www.acr.org/
Quality-Safety/Standards-Guidelines/Practice-Guidelinesby-Modality/MRI.
a 45-minute to 1-hour exam, we often
with any change in technology, to make
just can’t.”
As it turned out, the patient’s tumor
was responding and was almost
completely dissolved. “She had the
information she needed at the right
time and she left our center in a really
different place, knowing she was going
home to her family to let them know
2. Lakoma A, Kim ES, Minimally invasive surgical management
of benign breast lesions. Gland Surg, 2014 May; 3(2) 142-148.
sure everyone is trained, educated,
and on board with it, since it gives
the clinician the ability to visualize
breast tissue which may not be
imaged using other techniques such
as mammography or ultrasound. This
can aid in planning the next steps in
patient care.
the treatment is working.”
Constance Lehman, MD, PhD, FACR, is Director of Breast Imaging and Co-director of AVON Breast Center at Massachusetts General Hospital in Boston.
She received her MD and PhD from Yale School of Medicine, and completed her residency and fellowship at University of Washington Medical Center.
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