A method for assessing peripheral vascular disease (PVD) was developed from the pattern of transcutaneous oxygen (PtcO2) changes after temporary limb ischemia induced by pneumatic blood pressure cuff occlusion. The transcutaneous oxygen recovery half-time (TORT) was defined as the time required to recover half of the decrease in the limb/chest PtcO2 ratio produced by temporary limb ischemia. TORT was examined in subjects with and without significant PVD. Patients who underwent operative therapy for symptomatic PVD were studied before and after operation. Comparison was also made of the values of patients in whom therapy was successful in resolving symptoms vs. those in whom it was not. TORT was found to improve the diagnostic accuracy of PtcO2 measurements to differentiate normal vs. PVD limbs and successful vs. unsuccessful results of therapy. Normal subjects uniformly had TORT values less than or equal to 1.5 minutes at both calf and foot positions; limbs with symptomatic PVD consistently had TORT values that were significantly longer in duration (p less than 0.001). Limbs with PVD that received successful therapy had a significant improvement in calf and foot TORT values after surgery (p less than 0.01); postoperative values were usually slightly longer than those of normal subjects, probably reflecting some residual disease. Postoperatively, limbs with PVD that had received unsuccessful therapy either had only slight improvement or worsening of their TORT values, which were significantly greater than the TORT values of limbs that received successful therapy (p less than 0.001). We conclude that measurement of postocclusive TORT is a reliable method for diagnosing PVD and for quantitatively evaluating residual disease after operative therapy.(ABSTRACT TRUNCATED AT 250 WORDS)