CLINICAL and experimental research, developed recently, showed that the autonomic nervous system may influence the disturbance of the arterial circulation of the brain in cases of arterial thrombosis and ischemia.1 During investigations I have observed, in cases of cerebral embolism or thrombosis, clinical improvement following the physiologic interruption by blocking with an anesthetic or the surgical section of the sympathetic innervation of the arteries of the brain. This observation led me to investigate the changes caused by these operations in the brain circulation.
I studied some patients with neurologic disturbances due to disorders of the arterial circulation of the brain. The study of the cerebral circulation was done by injecting 12 cc. of thorotrast® (colloidal thorium dioxide) into the primitive carotid artery. Then the classic roentgenograms of the three phases (arterial, arteriovenous and venous) of the brain circulation were obtained. After this arteriographic study, I carried out on these