Measuring Noncalcified Coronary Atherosclerotic Plaque Using Voxel Analysis with MDCT Angiography: A Pilot Clinical Study

OBJECTIVE. The purpose of our study was to evaluate a new method using voxel analysis for quantifying noncalcified plaque in coronary arteries using MDCT angiography (MDCTA) compared with luminal stenosis by catheter coronary arteriography.MATERIALS AND METHODS. Forty-one normal and eight abnormal arterial cross sections with noncalcified plaque selected from 40 patients undergoing MDCTA were analyzed for percentage of stenosis and plaque volume using a voxel analysis technique.RESULTS. Using voxel analysis, the normal arterial wall thickness was determined to be 0.8 ± 0.4 mm. Attenuation values (in Hounsfield units) for normal segments ranged between 30 and 175 H and for abnormal (plaque-containing) segments ranged from -49 to 139 H (p < 0.05). Plaque volume measurements varied from 0.90 to 156 mm3 with good interobserver correlation (R2 = 0.9671). Percentage of stenosis correlated with quantitative coronary arteriography measurement (R2 = 0.55). Voxel analysis underestimated the percentage of stenosis (...