Magnetic resonance angiography of aorto-iliac disease

Background: Four different techniques for aorto-iliac magnetic resonance angiography (MRA) were assessed for accuracy using a digital subtraction angiography (DSA) gold standard. Surgeons’ confidence in their ability to generate treatment plans with MRA and DSA was assessed, in consultation with a radiologist. Methods: Two different two-dimensional (2D) time-of-flight (TOF) sequences, a phase-contrast sequence, and a contrast-enhanced (CE) MRA sequence were used. Receiver operating characteristic (ROC) curves were plotted and areas (Az) calculated from radiologists’ readings. Surgeons’ confidence in their ability to utilize the images for treatment planning was assessed with a 5-point Likert scale. Thirty-six patients were evaluated. Results: CE MRA had a sensitivity, specificity, and Az of .92, .93, and .96, respectively, for stenoses 50% or greater. CE MRA performed better than other sequences, but the improvement compared with gated 2D TOF was not statistically significant. Interobserver agreement for CE MRA and DSA yielded identical Kappa values. Surgeons were most confident in DSA, followed by CE MRA, which was significantly preferred to other techniques. Conclusions: CE MRA closely approximates DSA in terms of diagnostic accuracy. Surgeons considering treatment plans are confident in the CE MRA technique, relative to other MRA methods.