Effect of xenon-induced flow activation on xenon-enhanced computed tomography cerebral blood flow calculations.
Computer simulations of stable xenon ((S)Xe) uptake curves were used to evaluate the effect of xenon-induced flow activation on CBF calculations by xenon-enhanced computed tomography. Estimates of flow activation were based on repeated transcranial Doppler measurements of blood velocity during 4.5 minutes of (S)Xe inhalation. The synthetic curves were generated from a generalized Kety equation that included time-varying blood flow activation. In contrast to the peak 35% increase in blood flow velocity during (S)Xe inhalation, a standard analysis of the flow-varying synthetic curves revealed only minor 3% to 5% increases in calculated CBF. It is concluded that brief xenon inhalations can provide blood flow estimates that contain minimal bias from activation.
Obrist
W D
WD
Department of Neurosurgery, University of Pittsburgh, Pennsylvania, USA.
Zhang
Z
Z
Yonas
H
H
D000280:Administration, Inhalation; D001783:Blood Flow Velocity; D001921:Brain / Q000098:blood supply* / Q000000981:diagnostic imaging*; D002536:Cerebral Arteries / Q000502:physiology; D002560:Cerebrovascular Circulation; D006801:Humans; D008955:Models, Cardiovascular; D014055:Tomography, Emission-Computed / Q000379:methods; D017585:Ultrasonography, Doppler, Transcranial; D014980:Xenon Radioisotopes / Q000008:administration & dosage
D014980:Xenon Radioisotopes