Hemodynamics of the Cortical and Deep Cerebral Regions in Patients with Occlusion of Cerebral Arterial Trunk

We measured cortical and deep cerebral blood flow(CBF) and cerebrovascular reserve capacity(CRC) using stable xenon computed tomography(Xe-CT) with acetazolamide test in 7 normal volunteers, 15 patients with internal carotid artery(IC) occlusion, 10 with IC stenosis, 10 with middle cerebralartery(MC) occlusion, and 11 with MC stenosis. Subsequent extracranial-intracranial(EC-IC) bypass surgery was performed in 22 of the patients. In the IC occlusion group, the cortical region showed decreased resting CBF compared with that in normals, while CRC was normal. Deep resting CBF in this group was reduced, but CRC was not. In this group, many patients showed matched low per fusion. In the IC stenosis group, cortical resting CBF showed normal range while cortical CRC was decreased. In the deep cerebral region, resting CBF and CRC were within the normal range. These findings indicated that in some patients with IC stenosis, normal CBF was maintained with vasodilation in the cortical regions. In the MC occlusion group, cortical resting CBF and CRC were both decreased. Deep resting CBF was also reduced, while deep CRC was within the normal range. Half of the patients in this group showed low per fusion with vasodilation. In the MC stenosis group, cortical resting CBF and CRC were both within the normal range. Deep resting CBF was reduced while CRC was within the normal range. The cortical region of many patients in this group showed normal hemodynamics. Bypass surgery did not increase resting CBF, but did increase CRC in the cortical region and putamen. The technique of Xe-CT combined with the acetazolamide test measuring of resting CBF and CRC in patients with occlusion of cerebral arterial trunk is useful in determing whether EC-IC bypass surgery is indicated.

cerebral blood flow

Xe-CT

actazolamide

crbrovascular reservecapaciy