The noninvasive assessment of aortoiliac disease: a comparison of dynamic isotope angiology with thigh brachial pressure index.

In 41 patients with severe claudication, the time taken for an intravenously injected isotope bolus of TC99m pertechnetate to pass from the aortic bifurcation to the common femoral arteries was measured using a gamma camera and computer. This isotope transit time (ITT) then was correlated with the severity of aortoiliac disease determined arteriographically. Highly significant differences in ITT were found between normal vessels and those with minor stenosis of less than 50%, major stenosis of 50% or more, or complete occlusion. With major disease there was a longer ITT than with minor disease (P less than 0.01). ITT gave a greater degree of differentiation between disease groups than did thigh/brachial pressure index, as measured by Doppler ultrasound in the same patients, and was not influenced by superficial femoral artery occlusion.