CH 14: duplex scanning and color flow imaging of the abdominal vessels

Duplex and color flow imaging at the aortoiliac vessels can determine the presence/absence of what pathology?

Significant stenosis

Duplex and color flow imaging at the aortoiliac vessels can follow up/evaluate what 2 structures/pathologies?

• Bypass grafts

• Aneurysms

Which structure can duplex and color flow imaging be used to determine the presence/absence of significant stenosis? 

Aortoiliac vessels

Which structure can duplex and color flow imaging be used to follow up on bypass grafts and evaluate aneurysms? 

Aortoiliac vessels 

Duplex and color flow imaging at the renal arteries determine if what sonographic finding is seen?

Significant stenosis greater than or equal to 60% diameter reduction

Which structure can duplex and color flow imaging be used to determine if a significant stenosis of greater than or equal to 60% diameter reduction is present? 

Renal arteries

Duplex and color flow imaging at the kidneys can determine the presence/absence of what pathologies/procedures? (2)

• Disease

• Transplants

Which structure can duplex and color flow imaging be used to determine the presence/absence of disease and evaluates transplants? 

Kidneys

Duplex and color flow imaging at the mesenteric arteries can determine the presence/absence of what pathology? 

Significant stenosis

Which structure can duplex and color flow imaging be used to determine the presence/absence of a significant stenosis? 

Mesenteric arteries

Stenosis of the mesenteric arteries can account for or cause what pathology? 

Chronic mesenteric bowel ischemia 

The stenosis of which structure can account for or cause chronic mesenteric bowel ischemia?

Mesenteric arteries

Duplex and color flow imaging at the liver can evaluate the presence/absence of what pathology/procedure? (2) 

• Portal hypertension

• Pre/post liver transplants

Which structure can duplex and color flow imaging be used to evaluate for suspected portal hypertension and evaluate pre/post liver transplants? 

Liver

List the 6 limitations of abdominal duplex and color doppler imaging.

• Patient body habitus

• Bowel gas

• Scar tissue from previous abdominal surgeries

• Rapid respirations

• Patient can’t hold their breath

• Non-fasting patient

1. With duplex and color flow imaging, the appropriate transducer should be selected according to patient ______.

2. For example, adults will have what kind of transducer and what frequency?

1. Size

2. Curvilinear, 5 MHz

1. In both the sagittal and transverse, doppler and color flow imaging can be used to evaluate _____________ and _______________ patterns.

2. The sonographer will observe for what 2 pathologies?

1. Grayscale, Color-flow

2. • Aneurysm

   • Plaque

In the sagittal plane and with duplex/color flow imaging, what should the doppler angle be set at for accurate PSVs?

Less than or equal to 60 degrees

What doppler angle is the standard/best for duplex imaging?

@ 60 degrees

Disregarding the arrows, what pathology is seen here?

Aneurysm (thrombus)

What doppler angle should be used for duplex imaging? 

Less than or equal to 60 degrees

What structures can be evaluated for an aortoiliac study? (8)

• Prox aorta

• Mid aorta

• Distal aorta

• Bifurcation

• Bilateral iliac arteries

• Celiac artery

• SMA

• Renal artery

What 2 things are kept in mind when measuring the aorta?

• Measured outer to outer

• Measured at maximum diameter

1. What structure is seen at the red arrow?

2. What structure is seen at the blue arrow?

1. Celiac artery

2. SMA

Label the crossed-out structures on this image. 

1. Celiac artery

2. Liver

3. SMA

4. Aorta

5. Vertebra

Label the crossed-out structures on this image. 

1. Hepatic artery

2. Venous confluence

3. IVC

4. Left renal vein

5. Aorta

6. Celiac artery

7. Splenic artery

Label the crossed-out structures on this image. 

1. Aorta

2. RT CIA

3. LT CIA

What velocity criteria is used for a stenosis at the aorta? (2)

• 2:1

• 4:1

What dilatation measurement qualifies as an aneurysm?

Greater than 3 cm

An increase in diameter of __% or more from the adjacent normal portion qualifies an artery as aneurysmal.

50%

List the 2 qualifications that label an artery aneurysmal.

• Dilatation greater than 3 cm

• Diameter greater than 50%

List the 2 qualities of a majority of AAAs. 

• Atherosclerotic

• Infrarenal

A majority of AAAs are located where?

Infrarenal

When an aneurysm is found, what 2 factors should be noted?

• Type of aneurysm

• Presence of thrombus

When examining an aneurysm, the sonographer should take note of what kind of aneurysms is here? (3)

• True (fusiform/saccular)

• False/Pseudo

• Dissecting

What is the most frequent complication of an AAA?

Rupture

What are the 2 complications of an AAA? 

• Rupture

• Embolization

What are the 2 primary complications of peripheral arterial aneurysms?

• Thrombosis

• Embolization

What is the most frequent complication of peripheral arterial aneurysms?

Embolization

It is not uncommon for both abdominal and peripheral aneurysms to contain varying amounts of what?

Thrombus

Label the crossed-out structures on the image.

3. What pathology is this?

1. Liquefaction

2. Thrombus

3. Thrombus within aneurysm

Label the structures crossed out on this image. 

3. What pathology is this? 

1. True lumen

2. False lumen

3. Dissecting aneurysm

What pathology is seen here?

Pseudoaneurysm

What pathology is seen here?

Aneurysm with thrombus

Many patients having a renal doppler study present with what clinical symptom?

Systemic hypertension

Define ‘systemic hypertension.’

Sustained elevated arterial blood pressure

Systemic hypertension can occasionally be caused by what other pathology? 

Renal artery stenosis

Renal artery stenosis can be secondary to what 2 pathologies?

• Atherosclerosis

• Fibromuscular dysplasia

Fibromuscular dysplasia is __________.

Hereditary

Fibromuscular dysplasia could be related to…

Hormones

Fibromuscular dysplasia is seen mainly in which gender?

Women

Which structure is fibromuscular dysplasia commonly seen in?

Renal arteries

1. Renal artery stenosis _______ blood flow to the kidney 

2. In return, the kidney produces the enzyme ______

3. Which will promote the conversion of ______________ to __________

4. This will result in ___________

5. Which will cause _____________ of the blood vessels 

6. The result of this process is called _____________________

1. Reduces

2. Renin

3. Angiotensinogen

4. Angiotensin

5. Hypertension

6. Vasoconstriction

7. Renovascular hypertension

The narrowing of the renal arteries (renal artery stenosis) reduces blood flow to the kidneys. 

What does the kidney do in response to this?

Produce the enzyme, renin

When the kidneys produce renin, what will it promote?

Conversion from angiotensinogen to angiotensin

1. The conversion of angiotensinogen to angiotensin will result in what pathology?

2. What does this pathology cause?

1. Hypertension

2. Vasoconstriction of the blood vessels

What is renovascular hypertension? (5)

Renal artery stenosis →

Renin production →

Angiotensinogen becomes angiotensin →

Hypertension →

Vasoconstricted blood vessels 

Name the pathology:

“The narrowing of the renal artery reduces blood flow to the kidney and in response, the kidney produces the enzyme renin, which promotes conversion of angiotensinogen to angiotensin, which results in hypertension which causes vasoconstriction of the blood vessels.”

Renovascular hypertension

What is the function of ‘angiotensinogen’?

Regulates BP

What is the function of ‘angiotensin’?

Increases BP

1. The appearance of these vessels are similar to what? 

2. What is the name of this pathology if renal artery stenosis is secondary to it? 

1. Beads

2. Fibromuscular dysplasia 

1. The appearance of these vessels are similar to what? 

2. What pathology is secondary to this pathology?

3. What is the name of this pathology?

1. Beads

2. Renal artery stenosis

3. Fibromuscular dysplasia

With varying renal doppler protocols, some can require velocity data from which 2 vessels at their proximal segments?

• Celiac artery

• SMA

Where is PSV typically obtained?

Distal to the SMA

Which 2 imaging planes can be used to locate the renal arteries? 

• Transverse

• Coronal

What is the landmark for finding the left renal artery in transverse?

Left renal vein

Where is the right renal artery found off of the aorta?

Anterolateral

When performing a renal doppler exam, what structure should still be evaluated bilaterally for their size and overall appearance? 

Kidneys

List the 6 arteries that can be dopplered for PSVs and EDVs for a renal doppler.

• Proximal renal arteries bilaterally

• Mid renal arteries bilaterally

• Distal renal arteries bilaterally

• Segmental arteries (upper/lower pole)

• Interlobar arteries (upper/lower pole)

• Accessory renal arteries

Where are the segmental arteries located on the kidneys?

Pelvis of the kidney

Where are the interlobar arteries located on the kidneys? (2)

• More distal and outward beyond the pelvis

• Not yet to the edge

1. What vessels represented by the short white arrows?

2. What vessels are represented by the long white arrows?

1. Interlobar arteries

2. Segmental arteries

Which 2 vessels are typically dopplered in the kidneys for a renal doppler?

• Segmental arteries

• Interlobar arteries

Label the crossed-out structures seen on this image. 

1. IVC

2. RRA

3. Aorta

4. LRA

5. LRV

1. What is seen in this image?

2. How will the sonographer doppler this image?

1. Accessory renal arteries

2. Doppler each one

What waveform is seen in the renal arteries?

Low resistance flow

What waveform is seen in the kidney arteries?

Low resistance flow

What waveform is seen in the aorta?

High resistive flow

What waveform is seen with vessels that are constantly feeding organs?

Low resistance flow

What does ‘RAR’ stand for?

Renal to aortic ratio

What is the formula for the RAR? 

Renal Artery PSV / Aortic PSV

This formula is used to calculate the…

RAR

What is a normal RAR?

Less than 3.5

What is an abnormal RAR?

Greater than or equal to 3.5

A RAR greater than or equal to 3.5 indicates a __% or greater diameter reduction.

60%

An RAR greater than or equal to 3.5 indicates what diameter reduction?

60% or greater

A PSV with post stenotic turbulence greater than 180-200 is suggestive of what diameter reduction?

Greater than or equal to 60%

What PSV with post stenotic turbulence is suggestive of a greater than or equal to 60% diameter reduction?

180-200

A PSV of greater than 180-200 with __________________ is suggestive of a greater than or equal to 60% diameter reduction 

Post stenotic turbulence 

Post stenotic turbulence should be…

Documented

List the 3 ways RAR may not be accurate.

• When AAA is present

• PSV of aorta is less than 40 cm/s

• PSV of aorta is greater than 90 cm/s

Kidneys are examined for abnormalities.

List 2 examples. 

• Cysts

• Cortical thinning

What is the typical length measurement for the kidneys?

10 - 12cm

List the 2 other terms for end diastolic ratio (EDR).

• Parenchymal resistance ratio (PRR)

• Diastolic/systolic ratio (DSR)

Parenchymal resistance ratio is another term for what?

End diastolic ratio

Diastolic/systolic ratio is another term for what?

End diastolic ratio

What does ‘EDR’ stand for?

End diastolic ratio

What does ‘PRR’ stand for?

Parenchymal resistance ratio

What does ‘DSR’ stand for?

Diastolic/systolic ratio

What is used to characterize the vascular resistance in the kidney?

End diastolic ratio/Parenchymal resistance ratio/Diastolic-systolic ratio