The purpose of this study was to assess the diagnostic accuracy of dynamic computed tomographic angiography (dyn-CTA) in patients with critical lower leg ischemia.
A population of 29 patients with known peripheral arterial occlusive disease (Fontaine stage III or IV) was examined with a combined CTA protocol consisting of a standard CTA (s-CTA) of the lower leg runoff from the diaphragm to the toes and dyn-CTA of the calves (scan range, 48 cm; 8 phases; 3.5 seconds per phase, 100 kV; 120 mAs; contrast volume, 50 mL; flow rate, 5.0 mL/s). Digital subtraction angiography was performed on all patients and served as a reference standard. For each of seven lower leg artery segments, arterial contrast and diagnostic confidence for stenosis assessment (3-point scale) were tested for s-CTA and dyn-CTA. Similarly, stenoses of calf-segments were classified on a 3-point scale separately for s-CTA and dyn-CTA and were compared with digital subtraction angiography to assess diagnostic accuracy.
Compared with s-CTA, dyn-CTA resulted in significantly higher arterial contrast enhancement (68% vs 46% optimal contrast; P < 0.01) and higher diagnostic confidence (64% vs 48% fully confident, respectively, P < 0.05). Dyn-CTA had a slightly higher sensitivity for the detection of significant stenosis (98.0% vs 96.6%), and for the detection of occlusion (95.4% vs 94.4%). Specificity for dyn-CTA was higher than for s-CTA, both for detection of stenosis (97.1% vs 92.2%) and especially for the detection of vessel occlusions (99.3% vs 94.4%; P < 0.05).
Compared with s-CTA, dyn-CTA provides improved arterial contrast enhancement, higher diagnostic confidence, and increased diagnostic accuracy for the detection of stenoses and occlusions in peripheral arterial occlusive disease patients.
Supplemental Digital Content is available in the text.
From the Departments of *Clinical Radiology and †Surgery, University Hospitals-Grosshadern, Ludwig-Maximilians University, Munich, Germany.
Received June 12, 2011, and accepted for publication, after revision, November 27, 2011.
Conflicts of interest and sources of funding: none declared.
Reprints: Wieland H. Sommer, MD, Department of Clinical Radiology, University of Munich, Grosshadern Campus, Marchioninistr 15, 81377 Munich, Germany. E-mail: email@example.com.
Supplemental digital contents are available for this article. Direct URL citations appear in the printed text and are provided in the HTML and PDF versions of this article on the journal’s Web site (www.investigativeradiology.com).