A study of 363 patients with arterial occlusion and 50 normal adults tested the value of the ultrasound technique and xenon 133 (133 Xe) clearance in providing objective assessments of clinical ischemia. By comparing ankle systolic and brachial systolic pressures detected by ultrasound, an ischemic index was calculated. This correlated directly with the degree of ischemia present on clinical evaluation.
Intermittent claudication was quantitated in a special study group and serial systolic ankle pressures and 133Xe muscle clearance recorded. A strong inverse relationship was noted between postexercise ankle pressure and isotope muscle clearance. Muscle hyperemia with attendant 133Xe clearance preceded ankle pressure rise but both pressure and clearance reached a simultaneous plateau.
The pressure-flow patterns were directly related to number and location of anatomic arterial occlusions.