Pseudoaneurysm: find the neck

Question 1A patient has a groin swelling two days after coronary angiography. Colour Doppler shows swirling red and blue flow inside a round sac. What is the next step?

1. aAspirate the sac to exclude infection
2. bDiagnose a haematoma and discharge with safety-netting advice
3. cLook for a neck between the sac and the artery and sample it with pulsed-wave Doppler
4. dApply firm compression over the sac for twenty minutes

Question 2What does the to-and-fro waveform in the neck of a pseudoaneurysm show?

1. aNo flow, because clot fills the neck
2. bVenous flow which varies with breathing
3. cFlow into the sac in systole and back to the artery in diastole
4. dContinuous flow away from the artery throughout the cardiac cycle

Question 3A groin collection after a femoral line shows no flow on colour Doppler, with the scale set low. What is it most likely to be?

1. aA pseudoaneurysm
2. bAn arteriovenous fistula
3. cA true aneurysm
4. dA haematoma

Question 4A person who injects drugs presents with a hot, pulsatile lump in the groin. A colleague plans to incise and drain it. What do you do first?

1. aScan it with colour Doppler before anyone uses a needle or blade
2. bAspirate it with a fine needle to confirm pus
3. cProceed with drainage under local anaesthetic
4. dStart antibiotics and drain it the next day

Question 5How does a true aneurysm differ from a pseudoaneurysm on ultrasound?

1. aA true aneurysm never contains clot
2. bThe artery itself is wider, with its own wall all the way round and no separate neck
3. cA true aneurysm shows no flow on colour Doppler
4. dA true aneurysm shows to-and-fro flow in a narrow neck