CHANGES IN CEREBRAL BLOOD-FLOW ESTIMATED AFTER STELLATE GANGLION BLOCK BY SINGLE-PHOTON EMISSION COMPUTED-TOMOGRAPHY

The validity of the hypothesis that the cerebral vasculature is under the control of sympathetic innervation was investigated using brain sc intigraphy imaging before and after stellate ganglion block (SGB). The experiment with HM-PAO showed a definite increase in the blood flow o f the brain on the block side on both by the dynamic images and the SP ECT images. The tympanic temperature (Tty) of the block side decreased significantly after SGB, compared to the unblock side in this study, as had been reported before. This change in Tty coinsided with the inc rease in cerebral blood flow as mentioned above. This study demonstrat ed that the cerebral vasculature is under the control of sympathetic i nnervation, the pathway of which is relayed and/or passes through the stellate ganglion. We conclude that SGB increases intracerebral blood flow and can also exert secondary effects systemically due to CNS bloo d flow changes as have been previously reported.