This Article Full Text (PDF) Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content

Answers to multiple-choice questionnaire: Vascular radiology [from Imaging 13(5)]

	Answers

Top Answers

1. False. Steroids may reduce the incidence of repeat reactions but they are usually of similar severity to the initial reaction [2].
   
2. False. Severe reactions occur in roughly 1 in 3000–10 000 patients.
   
3. False. There is no evidence to suggest that risk decreases with time since exposure.
   
4. True. This is essential to minimize the risk of repeat reaction.
   
5. True. Hydration is vital if nephrotoxicity is to be minimized.
   

References: (1) Kessel DO, Robertson I, Patel JV, Simpson S, Taylor EJ. Angiographic strategies when iodinated contrast medium is undesirable. Imaging 2001;13:349–56.[Abstract/Free Full Text] (2) Freed KS et al. AJR 2001;176:1389–92[Abstract/Free Full Text].

Answer 2

1. True. Most patients experience some discomfort during carbon dioxide (CO₂) angiography. Approximately 1 in 20 patients find the procedure intolerable.
   
2. True. CO₂ gas is very cheap.
   
3. False. High injection rates are normal.
   
4. False. CO₂ gas is excreted on its first passage through the lungs.
   
5. False. This is an excellent indication for using CO₂.
   

Reference: Kessel DO, Robertson I, Patel JV, Simpson S, Taylor EJ. Angiographic strategies when iodinated contrast medium is undesirable. Imaging 2001;13:349–56.

Answer 3

1. True. Doppler ultrasound is unreliable unless strongly positive.
   
2. False. MR angiography (MRA) may give excellent depiction of the distal circulation, including the pedal vessels.
   
3. True. This is an excellent indication for MRA.
   
4. False. There are several MRA techniques, some of which rely solely on blood flow.
   
5. False. The resolution of conventional angiography is sub millimetre; the resolution of MRA is typically 2–4 mm and is limited by signal-to-noise ratios.
   

Reference: Kessel DO, Robertson I, Patel JV, Simpson S, Taylor EJ. Angiographic strategies when iodinated contrast medium is undesirable. Imaging 2001;13:349–56.

Answer 4

1. True. This probably relates to expansion and the low viscosity of the gas.
   
2. False. Hand injection is just as effective.
   
3. True. This is essential to combat the effect of bolus fragmentation.
   
4. True. It is excellent in many forms of intervention.
   
5. False. Carbon dioxide angiography can be used to guide endovascular aneurysm repair. There is a risk of "vapour lock" causing mesenteric ischaemia. In practice, any excess gas is readily aspirated from the aneurysm.
   

Reference: Kessel DO, Robertson I, Patel JV, Simpson S, Taylor EJ. Angiographic strategies when iodinated contrast medium is undesirable. Imaging 2001;13:349–56.

Answer 5

1. False. Four, or theoretically more, detector elements are available.
   
2. False. Four slices are acquired simultaneously.
   
3. True.
   
4. True. Using ECG gating.
   
5. False. Subsecond gantry rotation is routine.
   

Reference: Schoepf UJ, Becker CR, Bruening RD, Ohnesorge BM, Huber A, Haw L-G, et al. Multislice CT angiography. Imaging 2001;13:357–65[Abstract/Free Full Text].

Answer 6

1. False. Good images of the cerebral circulation are possible.
   
2. False. A single injection is given.
   
3. True.
   
4. True.
   
5. False. Injection is intravenous.
   

Reference: Schoepf UJ, Becker CR, Bruening RD, Ohnesorge BM, Huber A, Haw L-G, et al. Multislice CT angiography. Imaging 2001;13:357–65.

Answer 7

1. True.
   
2. False. Both speed and detail are important.
   
3. False. Fast scan times allow breathless patients to be imaged.
   
4. False. Segmental and subsegmental arteries can be seen, as well as the venous return.
   
5. False. The entire chest can be scanned in 8 s.
   

Reference: Schoepf UJ, Becker CR, Bruening RD, Ohnesorge BM, Huber A, Haw L-G, et al. Multislice CT angiography. Imaging 2001;13:357–65.

Answer 8

1. True. Lesions may be missed on single projection images.
   
2. False. Pooled estimates in a recent meta-analysis showed MR angiography to be more sensitive and specific than colour duplex ultrasound.
   
3. False. Angiography is usually performed from the common femoral artery.
   
4. False. At present, catheter angiography remains the established method of imaging lower limb vessels.
   
5. True. CT angiograms using spiral or multislice CT scanners can be used to obtain peripheral angiograms.
   

Reference: Thomas SM. The current role of catheter angiography. Imaging 2001;13:366–75[Abstract/Free Full Text].

Answer 9

1. False. Catheter angiography is being largely replaced by less invasive imaging techniques for diagnostic imaging purposes.
   
2. False. In some centres carotid endarterectomy is performed without angiography to assess carotid artery disease.
   
3. True. It is important to remember this when evaluating other imaging modalities as an alternative to catheter angiography.
   
4. False. Pulmonary embolic disease is usually best investigated by radionuclide imaging or CT, with angiography reserved for non-diagnostic cases.
   
5. True. Arteriography prior to endovascular repair of an abdominal aortic aneurysm can give valuable information that may not have been obtained from CT and enables measurements for device sizing to be checked.
   

Reference: Thomas SM. The current role of catheter angiography. Imaging 2001;13:366–75.

Answer 10

1. True.
   
2. False. Idiosyncratic anaphylactoid reactions can be life threatening.
   
3. True. Smaller calibre catheters reduce the risks of bleeding complications at the access site.
   
4. True. This is particularly a problem in diabetic or dehydrated patients and is attributable to the use of iodinated contrast media.
   
5. False. Non-ionic contrast media are associated with fewer complications attributable to the contrast agent and are more comfortable for the patient.
   

Reference: Thomas SM. The current role of catheter angiography. Imaging 2001;13:366–75.

Answer 11

1. False. Complications can be divided into three main groups: contrast medium related; access site complications; and catheter and general complications.
   
2. True. The presence of subarachnoid blood can obscure the cause of subarachnoid haemorrhage, such as a small berry aneurysm, so angiography is the most accurate way to establish the cause.
   
3. True. Angiography is not usually required prior to conventional surgical repair.
   
4. True. With improvements in non-invasive imaging techniques, the role of angiography for diagnosis is likely to decline further, but its role in association with intervention has an increasing role.
   
5. False. Most cases of gastrointestinal bleeding are now investigated by endoscopy in the first instance.
   

Reference: Thomas SM. The current role of catheter angiography. Imaging 2001;13:366–75.

Answer 12

1. True.
   
2. False. Specificities of 90–95% are described for the detection of stenoses greater than 50%.
   
3. True.
   
4. False. Phase contrast MRA is complicated, with long scan times.
   
5. False. Time-of-flight MRA is susceptible to such artefact. Contrast enhanced MRA overcomes these problems.
   

Reference: Khaw K-T, Griffiths PD. Non-invasive imaging of the cervical carotid and vertebral arteries. Imaging 2001;13:376–90[Abstract/Free Full Text].

Answer 13

1. False. Catheter angiography is poor at assessing plaque morphology.
   
2. False. These characteristics are more likely to predispose to embolic episodes.
   
3. False. An intimal–medial thickness greater than 1 mm is a predictor of poor cardiovascular prognosis.
   
4. True. Intrathoracic lesions, even asymptomatic ones, are uncommonly found in association with symptomatic carotid bifurcation disease.
   
5. False. The majority of carotid disease is asymptomatic.
   

Reference: Khaw K-T, Griffiths PD. Non-invasive imaging of the cervical carotid and vertebral arteries. Imaging 2001;13:376–90.

Answer 14

1. True.
   
2. False. Catheter angiography rarely demonstrates the flap.
   
3. True.
   
4. True.
   
5. False. Vertebral artery spectral patterns tend to be non-specific, and the transcervical segments are difficult to image owing to surrounding bone.
   

Reference: Khaw K-T, Griffiths PD. Non-invasive imaging of the cervical carotid and vertebral arteries. Imaging 2001;13:376–90.

Answer 15

1. False. 5% are due to Marfan's disease.
   
2. False. Only 10% of patients with type A and 40% of patients with type B will be alive at 1 year if untreated.
   
3. False. Stanford type A dissections usually extend into the descending thoracic aorta.
   
4. True.
   
5. False. The false lumen usually lies within the layers of the aortic media.
   

Reference: Gaines P. Endovascular management of dissection of the descending aorta. Imaging 2001;13:391–8[Abstract/Free Full Text].

Answer 16

1. False. A chest radiograph is often of limited quality in this group of patients, and over one-quarter of patients will not have diagnostic features, even on a good quality image.
   
2. True.
   
3. True.
   
4. False. Aneurysmal dilatation of the thoracic aorta is an indication for intervention, even in type B dissections.
   
5. True.
   

Reference: Gaines P. Endovascular management of dissection of the descending aorta. Imaging 2001;13:391–8.

Answer 17

1. True.
   
2. False. Most interventional vascular suites contain the equipment needed for fenestration.
   
3. False. They are placed in the true lumen.
   
4. True. In the chronic phase the flap becomes thickened and much more fixed.
   
5. False. Chronic dissections have also been successfully treated.
   

Reference: Gaines P. Endovascular management of dissection of the descending aorta. Imaging 2001;13:391–8.

Answer 18

1. False. It is an out-patient procedure.
   
2. True.
   
3. False. To investigate both legs from the aorta to the ankles usually takes longer using duplex ultrasound.
   
4. False. This is a highly operator-dependent investigation.
   
5. False. Duplex ultrasound uses sound waves.
   

Reference: Hartshorne TC. Lower limb vascular assessment by ultrasound. Imaging 2001;13:399–405[Abstract/Free Full Text].

Answer 19

1. False. A diameter reduction of 50% or more is considered to be significant.
   
2. False. The spectrum is broader distal to a stenosis.
   
3. True. This indicates a 50% stenosis or greater.
   
4. True.
   
5. True. This is often how colour flow is used. First, colour flow is used to identify areas of turbulence and this is then investigated further with Doppler.
   

Reference: Hartshorne TC. Lower limb vascular assessment by ultrasound. Imaging 2001;13:399–405.

Answer 20

1. True. Bowel gas reflects the ultrasound beam.
   
2. False. This may be used as an acoustic window.
   
3. True. Again, this may reflect the ultrasound beam casting the arterial lumen into shadow.
   
4. True. An inappropriate Doppler angle (>60°) gives false results of velocity measurements.
   
5. False. These are ideally placed vessels for duplex because bowel gas, bones etc. do not get in the way of insonation.
   

Reference: Hartshorne TC. Lower limb vascular assessment by ultrasound. Imaging 2001;13:399–405.

This Article Full Text (PDF) Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Search for Related Content