DIAGNOSIS OF LOWER LIMBS ARTERIAL OCCLUSIVE DISEASE BY USING CT. AND DSA.

Abstract

The purpose of this study was to compare the accuracy of computed tomographic (CT) angiography with conventional digital subtraction angiography as reference standard in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial occlusive disease. A total of 30 consecutive patients (21men with mean age of 60±11.5 years and 9 women with mean age of 59±14 years). The patients underwent both conventional DSA and 16–detector row CT angiography. For data analysis, the arterial vascular system was divided into 35 segments. A total of 1050 arterial segments were analyzed for arterial stenosis by two independent blinded readers using a four-point grading system (grade 1, <10% luminal narrowing; grade 2, 10%–49% luminal narrowing; grade 3, 50%–99% luminal narrowing; grade 4, occlusion). CT angiographic and conventional DSA findings were diagnostic in all vascular segments. Compared with conventional DSA, the sensitivity and specificity of 16–detector row CT angiography with regard to detection of hemodynamically significant stenosis in all 35 arterial segments were 96.4% and 95.8%, respectively. CT reader overestimated arterial stenosis in (3%) of arterial segments, and underestimated arterial stenosis in (1%) of arterial segments. Presence of anteroposteriorly located luminal narrowing and extensive vascular wall calcification, were considered main reasons for disagreements between imaging modalities. Sixteen–detector row CT angiography is an accurate and reliable noninvasive alternative to conventional DSA (with an accuracy of 96%) in the assessment of aortoiliac and lower extremity arteries in patients with peripheral arterial occlusive disease.