Marcus Treitl MD, Presenter: Nothing to Disclose

Stefan Wirth MD, Abstract Co-Author: Nothing to Disclose

Christoph Degenhart, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

To compare measurements of the diameter of the vessel lumen and quantification of stenosis in the superficial femoral artery (SFA) by angiography-based algorithms such as calibration of a catheter tip, calibration of calipers or visual estimation with measurements by intravascular ultrasound (US). To evaluate their impact on the assessment of balloon size.

30 consecutive patients with untreated SFA stenosis had digital subtraction angiography (DSA) and intravascular US before intervention. Measurements of the diameter of the native vessel lumen were made twice by two experienced radiologists with all algorithms and methods in a standardised vessel segment. Intermethod and interobserver differences were calculated. Resulting balloon sizes and calculations of the degree of stenosis were compared.

Mean vessel diameter was 5.72mm for intravascular US, 6.56mm for calipers calibration, 5.99mm for calibration of the catheter tip and 4.67mm for visual estimation. Resultant balloon sizes were 6.0mm, 7.0mm, 6.0mm, and 5.0mm, respectively. Mean degree of diameter stenosis was 78.8% for intravascular US, 81.6% for calipers calibration, 79.7% for catheter calibration and 88.8% for visual estimation. Inter-reader variability was best for intravascular US (0.994; p<0.0001), and worst for visual estimation (0.384; p<0.099). Intermethod correlation was best for intravascular US and calibration of a catheter tip (0.881; p<0.0001).

Measurements of the diameter of the vessel lumen and quantification of stenosis of the SFA based on DSA equipment calibrated to a catheter tip, correlate best with direct intravascular measurements by US. Visual estimation can lead to small balloons and overestimation of stenosis.

Our study demonstrates the pitfalls of vessel lumen diameter measurements during interventional treatment of PAD and gives clear recommendations for the daily practice.

Treitl, M, Wirth, S, Degenhart, C, Reiser, M, Measurement of the Diameter of the Vessel Lumen and Quantification of Stenosis in the Superficial Femoral Artery before Intervention: Algorithms Based on Angiograms Compared with Visual Estimation and Measurement by Intravascular Ultrasound.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6018323.html