Cerebral blood flow measured with intracerebral laser doppler flow
probes and radioactive microspheres.
Kirkeby, Ole J., Ingunn R. Rise, Lars Nordsletten, Sigmund Skjeldal,
Christian Hall, and Cecilie Ris[diaeresis]oe.
Institute for Surgical Research and Department of Neurosurgery, The
National Hospital, University of Oslo, N-0027 Oslo, Norway
APStracts 2:0355A, 1995.
We have measured cerebral blood flow with intracerebral laser Doppler
microprobes in pentobarbital-anestethized pigs. We compared the
results to measurements from laser Doppler probes placed on the
surface of the brain and to blood flow estimation by the radioactive
microsphere method. The cerebral blood flow was varied by alterations
in inspired carbon dioxide, hemorrhagic hypotension, and high
cerebrospinal fluid pressure. The intracerebral probes and the
surface probes showed parallel responses to variations in cerebral
blood flow. The correlation was closest between surface probes and
the intracerebral probes measuring from the cerebral cortex (r=0.46,
p<0.005). The correlation coefficient between laser Doppler
flowmetry and radioactive microspheres was 0.41 (p<0.0005) for
all measurements. The correlation to microspheres was best for the
probes located 3 or 10 mm into the brain and poorest for the surface
probe. In conclusion, intracerebral laser Doppler flow measurements
reflect changes in blood flow, and the technique appears useful for
continuous estimates of cerebral blood flow.
Received 29 March 1994; accepted in final form 21 June 1995.
APS Manuscript Number A296-4.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 14 August 1995.