Doppler ultrasound assessment of the femoro-popliteal segment: comparison of different methods using ROC curve analysis.

Coexisting aorto-iliac and femoro-popliteal occlusive lesions remain a problem in vascular surgery. Arteriography does not provide information on their relative contributions to the presenting symptoms. The success of proximal reconstruction alone in such cases depends to some extent on the haemodynamic significance of the femoro-popliteal disease which will remain. Several noninvasive Doppler methods have been recommended for haemodynamic assessment of the femoro-popliteal segment. These methods were studied in 72 limbs of 38 patients. The results are compared using receiver operating characteristic curve analysis. The best single test in this group of patients was normalised transit time which was significantly better than pulsatility index damping factor (p less than 0.01). The addition of damping factor to normalised transit time tended to give some improvement but this was not statistically significant in the clinically relevant part of the ROC curve.