Usefulness of the 201TlCl exercise leg perfusion scintigraphy in arteriosclerosis obliterans (ASO). With evaluation of leg perfusion comparing before and after PTA

Twenty-eight patients of arteriosclerosis obliterans (ASO) complaining of intermittent claudication or pain at rest underwent symptom limited exercise leg perfusion scintigraphy using 201TlCl (Tl). Regions of interest (ROI) were drawn around each buttocks, thighs, calves and feet in whole body image, and we calculated Lesion/Normal Index (LNI) which was the devided value of the average count per pixel of each ROI of the affected side by that of the normal side. The average LNI of the foot was 0.81 and was smaller than other regions (p<0.05). Other region except foot showed Tl high uptake in affected side in some cases. Fifteen patients were compared after percutaneous transluminal angioplasty (PTA) with before PTA, and LNI of the foot statistically improved after PTA (p<0.005). The period suffering from disease of the group of Tl hight uptake in the affected leg was statistically shorter than that of the group of Tl non-high uptake (p<0.05). We supposed that the Tl uptake of the foot reflects ischemia of the leg sensitively, and high uptake of Tl in affected leg is concerned with compensatory change of microcirculation of ischemic leg in subacute period. This scintigraphy was thought to be useful to detect the ASO and to evaluate the effect of PTA, and was able to avail diagnosis and observation of the course of ASO patient. (author)