MultiHance-enhanced MR angiography of the peripheral run-off vessels in patients with diabetes

Abstract

Foot complications associated with diabetes are the most common cause of nontraumatic lower extremity amputations in the industrialized world. Advances in surgical revascularization techniques in patients with lower limb ischemia require precise preoperative imaging of the peripheral vessels with the ultimate aim of reducing the rate of major foot amputations in these patients. MultiHance-enhanced 3-D MR angiography has been shown to provide better vascular contrast enhancement and better vessel delineation than conventional gadolinium agents at equivalent dose. Moreover, MultiHance-enhanced MR angiography results in significant increases in sensitivity and specificity over unenhanced MR angiography when compared with intraarterial digital subtraction angiography as the reference standard. Specifically, the greatest benefit of MultiHance is noted in the smaller more distal vessels of the lower leg. This is of utmost importance in diabetic patients as the presence of a patent distal calf or pedal vessel enables distal bypass grafting, and thus may significantly change treatment planning. The optimal approach for delineating the peripheral vasculature seems to be the application of a hybrid dual bolus approach in which cruropedal arteries are acquired first using sagittal slabs and a time-resolved acquisition technique. This allows the calf and pedal arteries to become assessable in a continuous way and partial volume artifacts to be decreased in the slice direction. This is followed by a two- or three-station bolus chase MR angiography for assessment of the aortoiliac, femoropopliteal, and proximal calf vessels. Vessel imaging may be supplemented by imaging of soft tissues for delineation of associated inflammatory or necrotic complications in the diabetic foot.