title: A new technology for detecting cerebral blood flow: a comparative study of ultrasound tagged NIRS and 133Xe-SPECT.
abstract: There is a need for real-time non-invasive, continuous monitoring of cerebral blood flow (CBF) during surgery, in intensive care units and clinical research. We investigated a new non-invasive hybrid technology employing ultrasound tagged near infrared spectroscopy (UT-NIRS) that may estimate changes in CBF using a cerebral blood flow index (CFI). Changes over time for UT-NIRS CFI and 133Xenon single photon emission computer tomography (133Xe-SPECT) CBF data were assessed in 10 healthy volunteers after an intravenous bolus of acetazolamide. UT-NIRS CFI was measured continuously and SPECT CBF was measured at baseline, 15 and 60 min after acetazolamide. We found significant changes over time in CFI by UT-NIRS and CBF by SPECT after acetazolamide (P ≤ 0.001). Post hoc tests showed a significant increase in CFI (P = 0.011) and SPECT CBF (P < 0.001) at 15 min after acetazolamide injection. There was a significant correlation between CFI and SPECT CBF values (r = 0.67 and P ≤ 0.033) at 15 min, but not at 60 min (P ≥ 0.777). UT-NIRS detected an increase in CFI following an acetazolamide bolus, which correlated with CBF measured with 133Xe-SPECT. This study demonstrates that UT-NIRS technology may be a promising new technique for non-invasive and real-time bedside CBF monitoring.
authors.affiliation: Danish Headache Center and Department of Neurology, Glostrup Hospital, Faculty of Health Sciences, University of Copenhagen, 2600, Glostrup, Denmark. henrikschytz@hotmail.com
authors.forename: Henrik W
authors.initials: HW
authors.lastname: Schytz
authors.forename: Song
authors.initials: S
authors.lastname: Guo
authors.forename: Lars T
authors.initials: LT
authors.lastname: Jensen
authors.forename: Moshe
authors.initials: M
authors.lastname: Kamar
authors.forename: Asaph
authors.initials: A
authors.lastname: Nini
authors.forename: Daryl R
authors.initials: DR
authors.lastname: Gress
authors.forename: Messoud
authors.initials: M
authors.lastname: Ashina
mesh_terms: D000086:Acetazolamide; D000328:Adult; D000927:Anticonvulsants; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology*; D003422:Critical Care / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D012372:ROC Curve; D012016:Reference Values; D012680:Sensitivity and Specificity; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*; D014463:Ultrasonography / Q000379:methods*; D014980:Xenon Radioisotopes; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D014980:Xenon Radioisotopes; D000086:Acetazolamide