Pre-procedural and diagnostic imaging

Question 1

Expected size of common bile duct

Answer 1

• 6 mm for 60 and below
• After age 60, add 1 mm per decade of life

Question 2

Situations in which ERCP is contraindicated or barriers to ERCP

Answer 2

• Hx of pancreatitis
  *

Question 3

What is the first thing you do after obtaining ultrasound evidence of acute calculous cholecystitis with fever?

Answer 3

Antiboitics!!!

Piperacillin-tazobactam is ideal. A laporoscopic cholecystectomy should then be performed in 2-3 days.

Question 4

A-lines

Answer 4

A-lines are reverberation artifacts. They appear as hyperechoic, horizontal multiples of the distance between the ultrasound probe and the visceral-parietal pleural interface.

A-lines can be a normal finding in a healthy patient, although they are also seen in pathologic settings, including pneumothorax, COPD, asthma, and atelectasis.

Question 5

B-lines

Answer 5

• B-lines are well-defined, vertical, hyperechoic, comet-tail artifacts lines that arise from the hyperechoic pleural line, move with respiration (swinging flashlight appearance), and do not fade with depth.
• Multiple (≥ 3) B-lines may be seen in edema or fibrosis. The identification of fewer than 3 B-lines in a single field of view between two ribs is considered normal.
• B-lines are lost in pneumothorax.

Question 6

Loss of seashore sign

Answer 6

• Loss of seashore pattern is seen in pneumothorax

Question 7

If subcutaneous emphysema is suspected, the next steps are. . .

Answer 7

. . . bronchoscopy to confirm, then surgery to repair

Question 8

In the setting of trauma, CT is highly sensitive and specific for solid organ injury, but NOT for ____

Answer 8

In the setting of trauma, CT is highly sensitive and specific for solid organ injury, but NOT for hollow viscus injury

Question 9

In the setting of a stable trauma patient, the optimal CT is. . .

Answer 9

. . . one with contrast

Usually IV, but sometimes oral or rectal. Contrast is vital to the sensitivity of the CT for detection of traumatic injuries.

Question 10

What is CT good at vs bad at in the setting of abdominal trauma?

Answer 10

• Good at: Telling you whether the peritoneum or retroperitoneum is involved, or not
• Bad at: Telling you if there has been an injury to hollow viscera organs and if there is a diaphragmatic injury without hernia

Question 11

FAST exam cannot rule out. . .

Answer 11

. . . intra-abdominal injuries

It just isn’t sensitive enough. It is useful because it is fast, but a negative FAST exam does not mean that the patient is good to go.

It is worst at detecting diaphragmatic injuries and retroperitoneal injuries

Question 12

Imaging study of choice to diagnose bony metastases

Answer 12

MRI with contrast