Noninvasive ankle pressure measurements by oscillometry.

Noninvasive ankle systolic, mean and diastolic pressures were obtained with an oscillometric instrument available commercially. Systolic pressures were also measured at either the posterior tibial or dorsal pedal artery by using the Doppler technique with the ultrasound probe. Ankle pressures were obtained in normal subjects and in patients with peripheral vascular disease, particularly patients with calcified or incompressible vessels or with different posterior tibial and dorsal pedal Doppler pressures. Systolic pressures by oscillometry and by Doppler were equal in normal subjects and in functionally normal limbs of patients. In the presence of mild vascular disease, systolic pressure was decreased and mean and diastolic pressures were within normal limits. Measurements by Doppler and by oscillometry were similar. In patients with moderate disease, the systolic pressure by oscillometry, although decreased, was consistently higher than Doppler pressures, and the mean ankle pressure was decreased. In patients with different posterior tibial and dorsal pedal pressures, the systolic oscillometric pressure was closer to the highest Doppler pressure measured. In contrast, in patients with partially incompressible vessels, the systolic oscillometric pressure was consistently lower than Doppler pressures. The oscillometric instrument available did not detect pressure pulses in patients with severe vascular disease; the weak pressure pulses present can, however, be detected with more sensitive instrumentation.