TY - JOUR
T1 - In vivo cerebrovascular measurement combining diffuse near-infrared absorption and correlation spectroscopies
AU - Cheung, Cecil
AU - Culver, Joseph P.
AU - Takahashi, Kasushi
AU - Greenberg, Joel H.
AU - Yodh, A. G.
PY - 2001
Y1 - 2001
N2 - We combine two near-infrared diffuse optical techniques to study variations of blood flow, haemoglobin concentration, and blood oxygen saturation in the functioning rat brain. Diffuse correlation spectroscopy (or flowmetry) monitors changes in the cerebral blood flow, without the use of the principles of tracer clearance, by measuring the optical phase-shifts caused by moving blood cells. Near-infrared absorption spectroscopy concurrently measures tissue absorption at two wavelengths to determine haemoglobin concentration and blood oxygen saturation in this same tissue volume. This optical probe is non-invasive and was employed through the intact skull. The utility of the technique is demonstrated in vivo by measuring the temporal changes in the regional vascular dynamics of rat brain during hypercapnia. Temporal and spatial variations of cerebral blood flow, haemoglobin concentration and blood oxygen saturation during hypercapnia are compared with other measurements in the literature, and a quantitative analysis demonstrating the self-consistency of our combined observations of vascular response is presented.
AB - We combine two near-infrared diffuse optical techniques to study variations of blood flow, haemoglobin concentration, and blood oxygen saturation in the functioning rat brain. Diffuse correlation spectroscopy (or flowmetry) monitors changes in the cerebral blood flow, without the use of the principles of tracer clearance, by measuring the optical phase-shifts caused by moving blood cells. Near-infrared absorption spectroscopy concurrently measures tissue absorption at two wavelengths to determine haemoglobin concentration and blood oxygen saturation in this same tissue volume. This optical probe is non-invasive and was employed through the intact skull. The utility of the technique is demonstrated in vivo by measuring the temporal changes in the regional vascular dynamics of rat brain during hypercapnia. Temporal and spatial variations of cerebral blood flow, haemoglobin concentration and blood oxygen saturation during hypercapnia are compared with other measurements in the literature, and a quantitative analysis demonstrating the self-consistency of our combined observations of vascular response is presented.
UR - http://www.scopus.com/inward/record.url?scp=0034879422&partnerID=8YFLogxK
U2 - 10.1088/0031-9155/46/8/302
DO - 10.1088/0031-9155/46/8/302
M3 - Article
C2 - 11512610
AN - SCOPUS:0034879422
SN - 0031-9155
VL - 46
SP - 2053
EP - 2065
JO - Physics in medicine and biology
JF - Physics in medicine and biology
IS - 8
ER -