Regional cerebral blood flow and oxygen utilization in superficial temporal-middle cerebral artery anastomosis patients

✓ Regional cerebral blood flow (rCBF) and regional cerebral oxygen utilization (rCMRO 2 ) were measured before and after surgery in nine patients undergoing a superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis to bypass cerebrovascular lesions not amenable to extracranial operative procedures. The objective of these studies was to determine whether measurements of this type could provide objective criteria for surgery as well as assess the effect of surgery. The preliminary data, although limited, suggest that measurements of regional cerebral hemodynamics and metabolism in these patients before and after surgery provide valuable data upon which to develop criteria and assess results. For example, 1) a significant depression of rCBF and rCMRO 2 in patients in whom a major cerebral infarction has not occurred, or 2) relative preservation of rCMRO 2 despite depressed rCBF seem to be favorable indications for establishing a functioning STA-MCA anastomosis. In such patients, STA-MCA anastomosis can be followed by a return of rCBF and rCMRO 2 to virtually normal levels. Relatively normal rCBF and rCMRO 2 in the presence of an occluded internal carotid artery in asymptomatic patients indicates satisfactory collateral circulation and is probably a contraindication to surgery.