Replacement of invasive monitoring of cerebral venous oxygenation with noninvasive techniques offers great promise in the management of life-threatening neurologic illnesses including traumatic brain injury. We developed and built an optoacoustic system to noninvasively monitor cerebral venous oxygenation; the system includes a nanosecond Nd:YAG laser and a specially designed optoacoustic probe. We tested the system <i>in vitro</i> in sheep blood with experimentally varied oxygenation. Our results demonstrated that (1) the amplitude and temporal profile of the optoacoustic waves increase with blood oxygenation in the range from 24% to 92%, (2) optoacoustic signals can be detected despite optical and acoustic attenuation by thick bone, and (3) the system is capable of real-time and continuous measurements. These results suggest that the optoacoustic technique is technically feasible for continuous, noninvasive monitoring of cerebral venous oxygenation.
© 2002 Optical Society of America
(040.1880) Detectors : Detection
(110.7050) Imaging systems : Turbid media
(120.4290) Instrumentation, measurement, and metrology : Nondestructive testing
(170.1460) Medical optics and biotechnology : Blood gas monitoring
(170.4580) Medical optics and biotechnology : Optical diagnostics for medicine
Rinat O. Esenaliev, Irina V. Larina, Kirill V. Larin, Donald J. Deyo, Massoud Motamedi, and Donald S. Prough, "Optoacoustic Technique for Noninvasive Monitoring of Blood Oxygenation: A Feasibility Study," Appl. Opt. 41, 4722-4731 (2002)