FIRST RESULTS OF SPIRAL CT ANGIOGRAPHY IN THE EVALUATION OF CAROTID-ARTERY STENOSIS

Purpose: To determine the value of spiral CT angiography in Maximum Intensity Projection (MIP)-technique for evaluation of carotid artery stenosis. Methods: A comparison of the MIP technique with intraarterial DSA was done in 24 patients with 40 stenoses. Quantification of stenosis was determined according to the NASCET study: mild (0-29%), moderate (30-69%), severe (70-99%) and occlusion (100%). Results: Totally the correlation of spiral CT angiography with DSA was 80% (r = 0.93; p = 0.0001). In the moderate stenosis group (r = 1; p = 0.1573), severe stenosis group (r = 0.89; p = 0.002) and the occlusion group (r = 1; p = 0.0009) there was a good correlation with DSA. In the mild stenosis group (r = 0.55; p = 0.0704) correlation of spiral CT angiography with DSA was poor. Spiral CT angiography allows an excellent delineation of calcifications. Tandem lesions and collateral flow cannot be shown with spiral CT angiography. Conclusion: Intraarterial DSA remains the gold standard for evaluation of carotid artery stenosis, because DSA is the modality which shows the whole length of the carotid artery and yields information on tandem lesions and collateral flow.