Invited Commentary to:'The Value of Aortic Flush Angiography in Detecting Pedal Run-off Vessels in Diabetics'

Abstract

The aetiology of diabetic foot lesions is complex, involving ischaemia, neuropathy and infection in varying degrees of severity. The diagnosis and correction of ischaemia is the cornerstone of success in diabetic foot management. A wellperfused foot ailows pertbrming minor amputation and salvage procedures with optimal success. In addition, it enhances the management of infection (4). An understanding of the mechanisms leading to ischaemia is of fundamental importance in this clinical problem, which is observed with growing frequency since the populations of most Western societies are aging (1). When ischaemia occurs in the diabetic foot, it is due to atherosclerotic occlusive arterial disease. The underlying process does not appear to be different from that which occurs in nondiabetics, but symptomatic atherosclerotic occlusive disease is more commonly seen in diabetic patients. The progression of disease is more rapid. Calcification in the media is common; this is not associated with occlusion but may interfere with noninva. sive testing and may augment technical difficulties if vascular reconstruction is undertaken. There is a special pattern of" athemsclerosis that blocks the infragenicular arteries but spares the vessels of the foot to a certain degree and the dorsalis pedis artery in particular. It is important to recognize this because it gives the opportunity of distal arterial reconstruction of the inframalleolar vessels. Therefore, the treatment plan for diabetic foot lesions consists in (7): • abandoning the idea of micmvascular disease as the cause of ulceration, as comparatively seen in diabetic nephropathy • control of infection by treating it emergently • evaluation of the degree of ischaemia • vascular reconstruction to restore perfusion of the foot As a result of this, amputation rates have been reduced (7). The results of distal arterial reconstruction in diabetics are as good as or even better than those in nondiabetics. An aggressive surgical approach is justifiable. Distal bypass surgery with autogenous vein remains the therapy of choice in such far-progressed arterial lesions (2, 6, 8, 10). Diabetics need more distal bypasses and often require distal amputations. Foot lesions may present complex management problems and need multidisciplinary efforts. Age, smoking, hypertension and diabetes mellitus are recognized risk factors in such patients with limb ischaemia. Investigation of renal function should be considered by no means neglected as it is often impaired. Performing an angiogram might be indicated but could create a problem because the degree of renal insufficiency might increase. The most important information before a treatment plan may be instituted is whether or not there is a patent run-off vessel, which the vascular lumen reopening procedure or a graft can resupply. Over the past decade, angiography has been used as the gold standard for deciding whether or not this approach is practicable (2). This may pose a problem for the radiologist because of poor cardiac function or the limitations of contrast media injection in patients with poor kidney function. Techniques, especially in