What is the CPT code for transcutaneous oxygen measurements?

93922 Noninvasive physiologic studies of upper or lower extremity arteries, single level, bilateral (eg, ankle/brachial indices, Doppler waveform analysis, volume plethysmography, transcutaneous oxygen tension measurement)

93923 Noninvasive physiologic studies of upper or lower extremity arteries, multiple levels or with provocative functional maneuvers, complete bilateral study (eg, segmental blood pressure measurements, segmental Doppler waveform analysis, segmental volume plethysmography, segmental transcutaneous oxygen tension measurements, measurements with postural provocative tests, measurements with reactive hyperemia)