Usefulness of Abdominal Aortic Calcification for Screening of Peripheral Vascular Disease

ABSTRACT

PURPOSE: We wanted to evaluate the value of abdominal aortic calcification (AAC), as detected on CT, as a predictor of atherosclerotic stenotic disease of the lower extremity arteries. MATERIALS AND METHODS: One hundred three patients who had CT angiography performed for the evaluation of peripheral vascular disease were enrolled in this retrospective study. The volume (mm3) of the AAC was measured on CT. Each lower extremity was divided into 8 segments. The extent of stenosis of the lower extremity artery was manifested as the sum of the stenosis scores for 16 segments (total stenosis score TSS). The significant stenosis scores (SSS-50 and SSS-75) were defined as the sum of scores for the lower extremity artery segments that had significant stenosis of more than 50% and 75%, respectively. AAC was correlated to the TSS, SSS-50 and SSS-75 with using Spearman's correlation coefficient. The diagnostic performance of AAC for stenosis of a lower extremity artery of more than 50% and 75%, respectively, was evaluated by using the receiver operating characteristic (ROC) curve RESULTS: The Spearman's correlation coefficients were 0.728 (AAC vs. TSS), 0.662 (AAC vs. SSS-50), and 0.602 (AAC vs. SSS-75), respectively. For significant stenosis more than 50% and 75%, the areas under the ROC curve were 0.898 and 0.866, respectively. The cutoff value, sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 1030 mm3, 87%, 88%, 89%, 86% and 87% for stenosis more than 50% and 1030 mm3, 87%, 80%, 79%, 88% and 84% for stenosis more than 75%, respectively. CONCLUSION: Abdominal aortic calcification detected on CT may be a useful predictor of atherosclerotic stenotic disease of lower extremity arteries.