モヤモヤ病の脳循環動態(第1報)

蛍光.血管造影による脳表微小循環動態の検討

抄録

Fluorescein angiography (FAG) was performed during encephalo-myo-synangiosis on the cortical surface of the frontotemporal lobe in 15 hemispheres of 11 patients with moyamoya disease to study the epicerebral microcirculation. Initially, 0.05 ml/kg weight of 1 % sodium fluorescein was injected into the common carotid artery of the exposed brain, and about 5 minutes later, 5 ml of 10% fluorescein was injected into the peripheral vein. Fluorescence of the surface vessels was recorded photographically using an electric motor-driven camera and Kodak Tri-X pan film with 36 frames, taking up to 1.3 exposures per second.
The time interval between carotid injection of the dye and the first filling of the cortical arteries varied in each gyrus or in each part of each gyrus, and was markedly delayed in most parts. In seven hemispheres of seven patients, the vessels of some cortical surfaces were not filled even in the last frame, 26.9 seconds after carotid injection of the dye. By venous injection, however, the dye appeared in all vessels of the exposed areas before the last frame. Regional circulation time, which was the transit time of the dye from a small artery to a nearby small vein with the diameter of about 100 to 200μm, was prolonged in most parts and took more than 10 seconds in some areas of five hemispheres of four patients. The average regional circulation time took more than 5 seconds in six hemispheres of five patients. Extravasation of the dye was seen around the small arteries in some areas of five hemispheres of four patients.
FAG findings were well correlated with those of conventional cerebral angiography, especially with the filling pattern of the middle cerebral arteries, but were slightly correlated with the findings of preoperative computed tomographic scans and cerebral blood flow values measured by the ¹³³Xe inhalation method.
The heterogeneous patterns of the epicerebral microcirculation in patients with moyamoya disease were considered to be caused by the blood supply originating from multiple collateral pathways and by the extensive occlusion of the main arteries.