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Angiography
Outlines
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Introduction
X-ray aniography
CT angiography
Ultrasound angiography
MR angiography
Neuclear angiography
Introduction:
what is angiography?
An imaging technique used to visualize the blood
vessels
When to be used?
One of the reasons is to detect atherosclerotic (plaque)
disease in a blood vessel
Angiography imaging system
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Contrast agent
Catheter
Cathetarization lab
Outlines
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Introduction
X-ray aniography
CT angiography
Ultrasound angiography
MR angiography
Neuclear angiography
X-ray angiography
How does it work?
 Injecting contrast agent to blood stream
 Acquiring high contrast images .
 Excellent resolution (100 µm).
 visualize blood vessels and organs of the body
X-ray angiography image
X-ray angiography image
Why is x-ray angiography done
Why x-ray angiography is done?
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X-ray angiography is performed to specifically
image and diagnose diseases of the blood
vessels of the body, including the brain and
heart.
Therapeutic Angiographic Procedures.
X-ray angiography is performed to specifically
image and diagnose diseases of the blood
vessels of the body, including the brain and
heart.
X-ray angiography is performed to specifically
image and diagnose diseases of the blood
vessels of the body, including the brain and
heart.
Therapeutic Angiographic Procedures.
Contrast Agent
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Maximum contrast for minimum administrated dose.
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iodine Based contrast agent :
Iodine based contrast media are usually classified as ionic or
non-ionic.
X-ray parameters
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Diagnostic X-ray.
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15 ∼ 150 kV, rectified AC
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50 ∼ 400mA anode current
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tungsten wire (200 µm) cathode, heated to ∼ 2200◦C
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anode rotates at 3000 rpm
Techniques
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For all structures except the heart, the images are usually
taken using a technique called digital subtraction
angiography (DSA).
Digital subtraction angiography
Complications
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Major complications :
Cardiac arrhythmias , kidney damage, hypotension and
pericardial effusion.
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Minor complications :
Bleeding , blood vessel damage and allergic reaction to
the contrast.
Outlines
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Introduction
X-ray aniography
CT angiography
Ultrasound angiography
MR angiography
Neuclear angiography
Intravascular Ultrasound
angiography(IVUS)
Ultrasound basics
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Ultrasound is based mainly on pulse echo technique
To get the source of echo--->d =c(dt)/2 , c=1540m/s
IVUS : introducing the problem
What's problem with typical angiography ?
IVUS Basic idea
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IVUS is a tomographic imaging technique
IVUS image
What is expected to be seen?
1-the adventitia
2-the media
3-the intima
4-the lumen
System's hardware
Catheter :
sizes range between 2.6-3.5 French (0.87-1.17 mm)
compatible with a 6F guiding catheter
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Pullback device
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console
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how image is acquired?
IVUS image,cont.
Image modes:
 Typical 2-D image
IVUS image,cont.
Image modes:
L-Mode image
Image artifacts
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calcium shadow
Image artifacts ,cont.
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Coronary pulsation (motion artifact)
Benefits and limitations
Benefits:
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Cross sectional view
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non ionizing radiation
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No contrast agent is needed
Limitations:
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invasive
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Resolution (>150 um)
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Catheter size
Outlines
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Introduction
X-ray aniography
CT angiography
Ultrasound angiography
MR angiography
Neuclear angiography
Magnetic resonance
angiography(MRA)
MRA categories
Its divided into 2 categories:
1- flow dependant MRA
2-flow independent MRA
Flow dependant MRA
A- TOF MRA
B- PC MRA
TOF MRA pulse sequence
TOF MRA image
PC MRA
Flow Independant MRA
CE MRA:
Contrast enhanced MRA uses gd chalate as contrast
decreases makes its transverse magnetization small
which we will increase repetition time
Flow independent MRA image
Outlines
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Introduction
X-ray aniography
CT angiography
Ultrasound angiography
MR angiography
Neuclear angiography
Neuclear angiography
Introduction
A Nuclear angiography is a time-proven nuclear medicine test
designed to evaluate the function of the right and
left ventricles of the heart, thus allowing informed diagnostic
intervention in heart failure.
Nuclear angiography is typically ordered for the following
patients:
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Known or suspected coronary artery disease, to diagnose the
disease and predict outcomes
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With lesions in their heart valves
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With congestive heart failure
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Who have had a cardiac transplant
Introduction,cont.
Nuclear angiography involves two techniques:
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First pass radionuclide angiography (FPRNA)
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Gated blood-pool imaging (GBPI)
GBPI is more widely used than FPRNA because multiple
projections are possible and because the effects of various
interventions can be assessed. Also, most laboratories have a
single-crystal Anger camera, which is better suited to GBPI.
First pass radionuclide angiography
(FPRNA)
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radionuclide technetium 99m pertechnetate is used in FPRNA
because it remains in the intravascular and extracellular spaces.
The camera is appropriately positioned against the chest and a
bolus of radionuclide injected rapidly into a vein.
The bolus passes freely through the right side of the heart, lungs,
left atrium and left ventricle
The changes in radioactivity with passage of the bolus through the
heart can be stored in a computer, which can then be instructed to
display a time-activity curve of the particular section of the heart
under study.
Analysis of these time activity or recirculation curves facilitates
detection of both left-to-right and right-to-left shunts
First pass radionuclide angiography
(FPRNA),cont.
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With FPRNA, pulmonary transit times can be measured by
recording the time between the appearance of the bolus of
radionuclide in the right ventricle and its appearance in the
left ventricle.
FPRNA can also be used to determine right-left stroke-count
ratios and ventricular volumes at different stages of the
cardiac cycle.
On first pass the highest resolution for assessing regional wall
motion is obtained with a multi crystal camera, which has a
high temporal but a poor spatial resolution
Gated blood-pool imaging
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Patients are injected first with a tin preparation that adheres to the
red blood cells and then with 99mTc, which labels those cells.
Gated studies can be performed in conjunction with, but following,
FPRNA.
A high count rate permits high spatial resolution.
Separation of the images of the cardiac chambers depends critically
on the position of the patient and the camera.
In GBPI, data collection is "gated" to the R wave of the
electrocardiogram, and the time from one R wave to the next is
divided into a series of intervals or frames.
The main use of GBPI is in the evaluation of many facets of
coronary artery disease, such as the detection of myocardial
ischemia with stress.
Gated blood-pool
imaging,cont.
The assessment of biventricular performance during exercise is
one of the more exciting uses of nuclear cardiology. It can be
performed with the patient either upright or supine on a
bicycle and is the first technique to allow continuous
assessment of ventricular function while many different
interventions are made.
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The patient exercises for 3 minutes at increasing workloads:
the first minute allows for stabilization of the heart rate; the
next 2 minutes allows for data collection.
Advantages and drawbacks of
Nuclear Angiography
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Radionuclide techniques are useful alternatives or complements to
conventional and invasive investigations of the heart.
One advantage of measurements from FPRNA is an acceptably low
intrinsic variability (+5%) for sequential long-term evaluation of patients
with cardiac diseases.
evaluation of many facets of coronary artery disease, such as the
detection of myocardial ischemia with stress.
A major limitation of GBPI is the need for an appropriate correction for
background activity, which can be up to 50% of the activity from regions of
the left ventricle.
Serial studies require repeated injections, which increase background
activity and the patient's exposure to radiation, thus limiting the ability to
use multiple projections or multiple physiologic or pharmacologic
interventions.
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