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CT angiography for the assessment of carotid stenosis

Catheter angiography (CA) has been the gold standard of carotid imaging for the assessment of carotid stenosis and has been used in all the major randomized controlled trials of carotid endarterectomy.1 Despite this, noninvasive carotid imaging is increasingly used instead of CA.2,3⇓ There are several reasons for this. The noninvasive methods are safe compared with CA, which still carries a mortality/morbidity rate of 0.5 to 1.3%.4,5⇓ Noninvasive testing can be done on an outpatient basis and is clearly preferred by patients.6 Many physicians believe that noninvasive testing is sufficiently sensitive and specific to be used in at least some situations before endarterectomy.7

Three major types of noninvasive carotid imaging are currently available: Doppler ultrasound (DUS), contrast-enhanced MR angiography (CEMRA), and CT angiography (CTA).3 Ultrasound has been used for carotid screening for many years, but major questions …