A prospective comparison of lower limb colour-coded duplex scanning with arteriography

Objective: To compare the diagnostic value of colour Duplex scanning with arteriography for the detection of arterial disease of the aortoiliac arteries, femoropopliteal arteries and the origins of the tibial vessels. Design: Prospective, semi-blind study. Setting Vascular laboratory and radiology department, University Hospital. Methods: A total of 1658 arterial segments in 148 limbs were studied both by colour Duplex scanning and digital subtraction arteriography. Individual arterial segments were classified on the basis of peak systolic velocity ratios < 2.0, greater than or equal to 2.0 or an absent doppIer signal, as 0-49%, 50-99% diameter reduced, or occluded. The same arterial segments were similarly classified on the basis of arteriography and the two modalities were compared using a Kappa (k) analysis. Results: The overall agreement between arteriography and colour-coded Duplex ions k = 0.74 (95% CI, 0.70-0.78), this indicates substantial agreement. Kappa values (95% CI) from the aortoiliac, femoropopliteal and the origins of the infrapopliteal arteries were k = 0.59 (0.49-0.73; moderate agreement), k = 0.80 (0.76-0.84; substantial agreement) and k = 0.48 (0.35-0.61; moderate agreement) respectively. Conclusion: We conclude that there is substantial agreement between colour-coded Duplex and arteriography of the lower limbs, and that the ability of colour-coded duplex to plan and guide lower limb vascular interventions requires investigation.