Die Bedeutung der 64-Zeilen-Dual-Energy-CT-Angiographie in der Diagnostik von pAVK-Patienten mit kritischer Extremitätenischämie und/oder schweren Claudicatio-Beschwerden : Ein Vergleich der axialen Bilder mit dem Goldstandard der Digitalen Subtraktionsangiographie

The purpose of this study was to evaluate the diagnostic accuracy of dual-energy 64-row computed tomography angiography (CTA) in patients with symptomatic lower extremity peripheral arterial occlusive disease or critical limb ischemia, compared with conventional digital subtraction angiography (DSA) serving as the reference standard. DSA and CTA were consecutively performed in 99 patients (representing 198 cases). Classification of Stenosis (normal, mild, moderate, severe, occluded), extent of calcifications, image quality und artifacts were observed in cross-sectional images, visually in 2970 arterial segments by three radiologists. The CTA scorers were blinded. Accuracy, sensitivity and specificity have been calculated. Agreement between CTA scorers was evaluated by a Cohen kappa statistic. Of 198 cases 111 were assessable on both DSA and CTA. Sensitivity and specificity of CTA were 98% and 75% detecting significant stenosis. The calcification levels showed a significant effect on detecting the correct grade of stenosis. The agreement between both CTA readers was good. In conclusion 64-row dual-energy CTA is reliable for classification of significant stenosis in patients with suspected peripheral arterial occlusive disease. Limitations were shown in the different anatomic regions. In the pelvic region, it was the high degree of calcifications, which lead to difficulties in evaluation. In the crural and pedal region, the proximity between calcified vessels and bony structures caused suboptimal results. Considering the good results of this study, future developments, such