Abdominal Ultrasound

Question 1

Density on ultrasound

Answer 1

impedence

Question 2

Targetoid lesion in the liver

Answer 2

Highly likely to be metastatic disease

Question 3

Anechoic lesion in the liver

Answer 3

Likely a cyst

Question 4

Homogeneously mildly hyperechoic, well-defined lesion on liver ultrasound

Answer 4

Likely to be a hemangioma

Question 5

Posterior acoustic shadowing

Answer 5

Question 6

Reverberation

Answer 6

Question 7

Comet tail artifact

Answer 7

A type of reverberation artifact

Question 8

Ring down artifact

Answer 8

Due to trapping by air

Pathognomonic for the presence of air

Question 9

Twinkle artifact

Answer 9

Detects waveforms that vibrate within a structure - when that sturcture is very hard

“Motion” when there is none

Useful for detecting stones

Question 10

Pancreas ultrasound

Answer 10

Can often see the splenic vein running longitudinally along the pancreas

The SMA runs behind the splenic vein.

Question 11

Ultrasonographic pancreas anatomy

Answer 11

Question 12

How do you find the common bile duct?

Answer 12

Find the portal vein. Follow it up. The CBD will run alongside as it approaches the liver.

Follow the CBD out to ensure you haven’t mistakenly found the cystic duct.

It will also be the only tubular structure that does not light up on doppler.

Question 13

Serpiginous gallbladder

Answer 13

Totally normal variant

As long as the walls aren’t thickened and there are no stones, you’re good!

Question 14

How can you tell if ‘stuff’ in the gallbladder is sludge?

Answer 14

Ask the patient to move!

Question 15

Wall echo shadow sign

Answer 15

Question 16

CBD diameter

Answer 16

6 mm if under age 50

After 50, + 1 mm for every decade of life

Question 17

Hepatitis on ultrasound

Answer 17

“Starry sky” liver

The peri-vascular hyperemia is due to the infammatory exudate coming from the vasculature

Question 18

When is ultrasound not first line for a pulsatile abdominal mass?

Answer 18

• Patient is actively symptomatic
• Patient is too obese for an US to visualize the mass
  
  • In these cases, CT is preferred.
  • Theoretically, MRI could be used, but is expensive and slow, making it suboptimal in any real world scenario.

Question 19

Ddx for pulsatile abdominal mass

Answer 19

• AAA
• Tortuous aorta
• Nonvascular mass adjacent to the aorta

Question 20

What is the minimum diameter of the abdominal aorta in a male vs female that is considered aneurysmal?

Answer 20

Both 3.0 cm, but recommendations for female tend to be 0.5 cm sooner than for male as AAAs are at higher risk of rupture in females.

Question 21

Two groups for whom asymptomatic screening for AAA is indicated

Answer 21

• Males aged 65-75 who have ever smoked
• Males age > 60 who have a sibling or parent with hx of AAA