Value of duplex scanning in evaluation of crural and foot arteries in limbs with severe lower limb ischaemia - A prospective comparison with angiography

Objectives: To compare Duplex scanning with angiography for evaluation of crural and pedal arteries in limbs with lower limb ischaemia. Design: The findings obtained during Duplex scanning and angiography were prospectively compared in a blinded manner: Setting: Departments of Surgery, Diagnostic Radiology and Clinical Physiology, University Hospital. Materials: Duplex scanning and selective angiography of femoropopliteal, crural and foot arteries were performed in 40 limbs (38 patients, 480 segments) with intermittent claudication (n = 6), rest pain (n = 13) and ulcer/gangrene (n = 19). Each arterial segment were graded into four categories: normal, less than or equal to 50% diameter reduction, >50% diameter reduction and occlusion. Pedal arteries were evaluated as patency or occlusion of dorsal pedal artery and plantar arch. Chief outcome measures: Accuracy (AC), sensitivity (SE), specificity (SP), positive predictive (PPV), negative predictive (NPV) and kappa values. Main results: The Duplex scanning of the tibioperoneal trunk, crural and pedal arteries had an accuracy of 80% (kappa = 0.6). The SE, SP, PPV and NPV values were 83%, 77%, 79% and 81%, respectively. The SP was relatively low for the peroneal artery (58%) compared to the others. Conclusions: The results demonstrate the feasibility and reliability of Duplex scanning in detecting crural and pedal artery lesions in lower limbs with severe ischaemia.