3. CT. Data from the IRAD published in 2000 showed that among 464 patients with acute aortic dissections (62% with type A), nearly two-thirds underwent CTA as the initial diagnostic imaging. The computed tomographic data in this study were acquired on older generation scanners, which may explain the fact that most patients underwent
several imaging tests (average, 1.8 tests).129 A more recent IRAD publication, now including 894 patients,
showed that the ‘‘quickest diagnostic times’’ were achieved when the initial test was CT, whereas the initial use of MRI or catheterbased aortography resulted in significantly longer diagnostic times.