[Regional hemodynamic and metabolic consequences of temporo-sylvian anastomosis. Study of 15 patients by positron emission tomography].

Cerebral Blood Flow (CBF), Oxygen Extraction Fraction, and Oxygen utilization (CMRO2) have been studied in 15 patients before and After Extra-Intracranial Arterial bypass (EIAB), using PET and 150 steady-State Inhalation technique. Fourteen patients had carotid artery obstructive lesions and the last one a middle cerebral artery occlusion. In the whole group of patients, both CBF and CMRO2 increased significantly on both cerebral hemispheres after the EIAB. This effect was more marked in patients with extensive occlusive disease of neck vessels. This metabolic improvement afforded by EIAB in our patients suggests that long-standing hemodynamic failure may induce a metabolic depression that's still potentially reversible by surgical revascularization. On the other hand, improvement of focal CBF abnormalities depends, in our patients, upon the preoperative coupling of CBF-CMRO2 (mainly misery perfusion syndrome) as reported earlier.