Efficacy and sensitivity of axial scans and different reconstruction methods in the study of the ulcerated carotid plaque using multidetector-row CT angiography: comparison with surgical results.

BACKGROUND AND
PURPOSE: Carotid plaque ulceration is an important risk factor for stroke, and its diagnosis may be very important to plan a correct therapeutic approach. We hypothesized that axial scans and various reconstruction methods could have different specificity and sensitivity in the study of plaque ulceration. The object of this study was to evaluate their role and diagnostic efficacy in patients with carotid plaque complicated by ulceration through the comparison with surgical results.
MATERIALS AND METHODS: From January 2004 to November 2005, 109 patients who underwent a carotid endarterectomy were analyzed using CT angiography for a total of 218 carotid arteries. We assessed every carotid for the presence of ulcerations. For each patient axial image, maximum intensity projection (MIP), multiplanar reconstruction (MPR), shaded surface display (SSD), and volume rendering (VR) reconstructions were obtained.
RESULTS: Multidetector row CT angiography (MDCT) found 32 ulcerations; surgical confirmation underlined an overall 93.9% sensitivity (95% confidence interval [CI] 0.858-1.021), and a 98.7% specificity (95% CI, 0.961-1.012). Axial scans and volume rendering images demonstrated the highest sensitivity (90.9% and 87.9%, respectively); SSD, on the contrary, showed the lowest sensitivity: 39.4% (95% CI sensitivity, 0.227-0.561).
CONCLUSION: Axial scans plus VR reconstruction techniques offer superior depiction of carotid plaque ulceration compared with MIP, MPR, and SSD.