TY - JOUR
T1 - Comparison of thermal clearance measurement of regional cerebral blood flow with radiolabel led microspheres
AU - Hoehner, Paul J.
AU - Dean, J. Michael
AU - Rogers, Mark C.
AU - Traystman, Richard J.
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1987
Y1 - 1987
N2 - A thermal clearance technique for measuring cerebral blood flow is described and compared with the radiolabelled microsphere technique. The thermal technique involves measurement of the rewarming curve generated after bolus infusion of 4-5 ml of ice-cold saline into the common carotid artery with a subdural thermistor placed on the parietal cortex. Evaluation of the biexponential decay curves obtained with this technique demonstrated a close correlation with total hemispheric, parietal, and parietal gray blood flow determined by simultaneous microsphere measurement. Despite significant correlations (p <0.001), scatter in the data produced a broad 95% confidence interval, thus making interpretation of blood flow with the thermal clearance technique impossible. Furthermore, instrumentation with the thermal probe, which required opening of the dura, blunted the cerebral blood flow response to hypercapnia. We conclude that the major limitations of the thermal clearance technique include 1) nonhomogeneous clearance function, 2) significant variability, and 3) depression of CO2 reactivity. These limitations must be addressed before this technique can be used reliably in the laboratory.
AB - A thermal clearance technique for measuring cerebral blood flow is described and compared with the radiolabelled microsphere technique. The thermal technique involves measurement of the rewarming curve generated after bolus infusion of 4-5 ml of ice-cold saline into the common carotid artery with a subdural thermistor placed on the parietal cortex. Evaluation of the biexponential decay curves obtained with this technique demonstrated a close correlation with total hemispheric, parietal, and parietal gray blood flow determined by simultaneous microsphere measurement. Despite significant correlations (p <0.001), scatter in the data produced a broad 95% confidence interval, thus making interpretation of blood flow with the thermal clearance technique impossible. Furthermore, instrumentation with the thermal probe, which required opening of the dura, blunted the cerebral blood flow response to hypercapnia. We conclude that the major limitations of the thermal clearance technique include 1) nonhomogeneous clearance function, 2) significant variability, and 3) depression of CO2 reactivity. These limitations must be addressed before this technique can be used reliably in the laboratory.
KW - Cerebral blood flow
KW - Cerebral circulation
KW - Radiolabelled microspheres
KW - Thermal clearance
UR - http://www.scopus.com/inward/record.url?scp=0023265643&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0023265643&partnerID=8YFLogxK
U2 - 10.1161/01.STR.18.3.606
DO - 10.1161/01.STR.18.3.606
M3 - Article
C2 - 3590253
AN - SCOPUS:0023265643
SN - 0039-2499
VL - 18
SP - 606
EP - 611
JO - Stroke
JF - Stroke
IS - 3
ER -