title: Optoacoustic monitoring of cerebral venous blood oxygenation though intact scalp in large animals.
abstract: Monitoring (currently invasive) of cerebral venous blood oxygenation is a key to avoiding hypoxia-induced brain injury resulting in death or severe disability. Noninvasive, optoacoustic monitoring of cerebral venous blood oxygenation can potentially replace existing invasive methods. To the best of our knowledge, we report for the first time noninvasive monitoring of cerebral venous blood oxygenation through intact scalp that was validated with invasive, "gold standard" measurements. We performed an in vivo study in the sheep superior sagittal sinus (SSS), a large midline cerebral vein, using our novel, multi-wavelength optoacoustic system. The study results demonstrated that: 1) the optoacoustic signal from the sheep SSS is detectable through the thick, intact scalp and skull; 2) the SSS signal amplitude correlated well with wavelength and actual SSS blood oxygenation measured invasively using SSS catheterization, blood sampling, and measurement with "gold standard" CO-Oximeter; 3) the optoacoustically predicted oxygenation strongly correlated with that measured with the CO-Oximeter. Our results indicate that monitoring of cerebral venous blood oxygenation may be performed in humans noninvasively and accurately through the intact scalp using optoacoustic systems because the sheep scalp and skull thickness is comparable to that of humans whereas the sheep SSS is much smaller than that of humans.
authors.affiliation: Laboratory for Optical Sensing and Monitoring, Center for Biomedical Engineering, The University of Texas Medical Branch, 301 University Blvd., Galveston, TX 77555-1156, USA.
authors.forename: I Y
authors.initials: IY
authors.lastname: Petrov
authors.forename: Y
authors.initials: Y
authors.lastname: Petrov
authors.forename: D S
authors.initials: DS
authors.lastname: Prough
authors.forename: I
authors.initials: I
authors.lastname: Cicenaite
authors.forename: D J
authors.initials: DJ
authors.lastname: Deyo
authors.forename: R O
authors.initials: RO
authors.lastname: Esenaliev
mesh_terms: D000818:Animals; D049628:Body Size; D002550:Cerebral Veins / Q000502:physiology*; D002560:Cerebrovascular Circulation / Q000502:physiology*; D008991:Monitoring, Physiologic / Q000379:methods*; D010100:Oxygen / Q000097:blood*; D061088:Photoacoustic Techniques / Q000379:methods*; D012535:Scalp; D012756:Sheep / Q000033:anatomy & histology* / Q000097:blood / Q000502:physiology*; D012815:Signal Processing, Computer-Assisted; D054063:Superior Sagittal Sinus / Q000502:physiology
chemical_list: D010100:Oxygen