Thomas Schertler MD, Presenter: Nothing to Disclose

Thomas Boehm MD, Abstract Co-Author: Nothing to Disclose

Hatem Alkadhi, Abstract Co-Author: Nothing to Disclose

Michael Krupa, Abstract Co-Author: Nothing to Disclose

Borut Marincek MD, Abstract Co-Author: Nothing to Disclose

Simon Wildermuth MD, Abstract Co-Author: Nothing to Disclose

Four-channel multi-detector row computed tomography (MDCT) of lower leg vessels showed a discordance with digital subtraction angiography (DSA). We sought to assess the diagnostic concordance of three different 16-channel MDCT slice widths (three different reconstruction techniques) with DSA in patients with lower leg peripheral arterial occlusive disease (PAD).

Seventeen patients suffering from symptomatic PAD of the lower legs prospectively underwent DSA and 16-channel CT angiography (CTA) within 7 days. CTA data were reconstructed using three slice widths and reconstruction increments (CT2/1: 2.0mm/1.0mm, CT1/.5: 1.0mm/0.5mm, CT.75/.4: 0.75mm/0.4mm). Quality of arterial vessel opacification and stenosis grades (0-9%, 10-50%, 51-99%, occlusion) in 163 vascular segments of the lower leg from DSA and the three CTA techniques were independently rated by two readers who were blind to the conditions. Using DSA as the gold standard, the sensitivity, specificity, and accuracy for detection of hemodynamically significant stenoses (>50%) were determined for the three CTA techniques.

DSA and CTA were successfully performed on all patients and were diagnostically conclusive. Arterial opacification was superior with CTA for all three reconstructions compared to DSA (P<0.001). The sensitivities for the detection of stenoses between CT2/1, CT1/.5, and CT.75/.4 were not significantly different (95.6%, 95.6%, and 97.5%, respectively). The corresponding specificities were 85.0%, 88.8%, and 95.3%, resulting in significant differences between CT.75/.4 and the other two CTA reconstruction techniques (P<0.001 and P<0.016). The accuracy of stenosis detection was 96.1% for CT.75/.4 ans was significantly higher compared with CT2/1 and CT1/.5 (P<0.05).

When using the highest possible longitudinal resolution, 16-channel CTA has an excellent diagnostic concordance with DSA for the assessment of PAD of the lower legs.

Schertler, T, Boehm, T, Alkadhi, H, Krupa, M, Marincek, B, Wildermuth, S, Slice Width Does Matter: Sixteen-channel Computed Tomography versus Angiography for the Evaluation of Lower Leg Peripheral Arterial Occlusive Disease.  Radiological Society of North America 2004 Scientific Assembly and Annual Meeting, November 28 - December 3, 2004 ,Chicago IL. http://archive.rsna.org/2004/4407023.html