Combining segmental systolic pressures and plethysmography to diagnose arterial occlusive disease of the legs.

Computer-assisted analysis of the data from SLP and PVR study of the legs with angiographically documented arterial occlusive disease, projected against a background of normal limbs, was used to assess the diagnostic value of each study, including its individual variables, as well as their varied combinations. The accuracy of both SLP and PVR interpretation was significantly improved by standarization against brachial values, but even with the aid of superimposed physician interpretation, each only reached 86 per cent when cases with multilevel occlusive disease were included. The combination of these two studies, which compensate for each other's limitations in several respects, achieved an overall accuracy of 97 per cent, with no errors observed in diagnosing either normal limbs or those with isolated occlusive disease. Objective diagnostic criteria for both SLP and PVR interpreatation are presented in algorithmic form.