AN EVALUATION OF I-123 IODOAZOMYCINARABINOSIDE AS A MARKER OF LOCALIZED TISSUE HYPOXIA IN PATIENTS WITH DIABETES-MELLITUS

Peripheral vascular disease is a serious and common complication in patients with diabetes mellitus (DM). Evaluation is, conventionally. by transcutaneous oxygen tension measurements (TcpO(2)), although this technique has some limitations in the evaluation of tissue viability. We have evaluated a new, radiolabelled, in vivo marker of tissue hypoxia, iodoazomycinarabinoside (IAZA), by comparing TcpO(2) measurements with patterns of iodine-123 IAZA uptake in ten patients (19 lower limbs) with DM and peripheral vascular disease using conventional gamma camera imaging techniques. Normal uptake patterns were seen in limbs in which normal TcpO(2) measurements were obtained. Diffusely increased uptake of [123]IAZA was seen in limbs with reduced TcpO(2). Focally increased uptake was seen in ulcers or in areas of atrophic skin change. A semiquantitative measure showed an inverse correlation between [123]IAZA and TcpO(2) values. These data suggest that tissue hypoxia can be imaged in this population of patients and that severity of disease can be assessed. A longitudinal prospective trial is now being developed.