POSTSURGICAL OBSERVATIONS OF MEAN HEMISPHERIC CEREBRAL BLOOD-FLOW WITH PATIENTS RECEIVING HIGH-FLOW EC-IC BYPASS USING A RADIAL ARTERY GRAFT (PRELIMINARY-REPORT, ONE-YEAR OBSERVATION OF 10 HEMISPHERES)

BACKGROUND When we encounter an inaccessible internal carotid artery l esion, we sacrifice the inaccessible internal carotid artery and, at t he same time, establish a high-flow extracranial-to-intracranial arter ial bypass (EC-IC bypass). Questions and concerns remain, however, abo ut the dynamics of the patient's cerebral blood flow postoperatively. METHOD Ten hemispheres from 9 patients had received radial artery graf ting as an EC-IC bypass with the simultaneous obstruction of the inter nal carotid artery. Their mean hemispheric cerebral blood flow (mCBF) was measured longitudinally during 1 year after surgery by single phot on emission computed tomography (SPECT) and a (133)Xenon-inhalation me thod. RESULTS The serial mCBF values of the five hemispheres with gian t aneurysm or paracavernous meningioma were attenuated during the post operative 3-month period and then returned to the normal range. In onl y one case did the postoperative reduction of mCBF fail to return to n ormal; in addition there was a memory disturbance that had developed a nd progressed, Five hemispheres with the ICA stenosis did not present reduction in mCBF. In three out of five hemispheres, transient elevati on of mCBF at 1 month after surgery was observed. CONCLUSIONS We concl ude from our study that the internal carotid artery can be safely subs tituted by the radial artery graft from the view point of cerebral blo od flow.