抄録
Measurement of cerebral blood flow (CBF) utilizing the less invasive Laser Flow Meter (LFM) can be used to assess the functionality of the system. Flow, velocity, mass (sampling volume), and their relations were estimated by simulation models. Anaesthetized adult mongrel cats (19) were used. A craniectomy was performed to introduce probes and make lesions. Models with cold injuries and saline infusions were used for eliciting abnormal CBF. In the white matter of saline infused animals, a comparison of CBF evaluated by hydrogen clearance method was made. The effects of intravenously infused Evans blue dye on the changes in CBF were evaluated.
A linear correlation between flow and speed is presented. The correlation between mass and concentrations of the reflected particles (beads) approximated a Iogarithmic curve. CBF from hydrogen clearance correlated well with LFM. Simultaneous increasing in CBF and velocity in the gray matter surrounding the cold lesion accompanied increases in cerebral blood volume with some time delays, Several cautions concerning measurement with LFM are discussed. LFM is convenient for real-time observation of CBF. Changes in mass in animals in relation to blood volume may be underestimated because of multiple scattering.
