Cerebral Hemodynamics and Oxygen Metabolism in Patients with Moyamoya Syndrome Associated with Atherosclerotic Steno-Occlusive Arterial Lesions

Abstract

Background: Patients with major cerebral artery steno-occlusion and the formation of the moyamoya-like vessels associated with some other disorders have been distinguished from moyamoya disease and classified as moyamoya syndrome. The hemodynamic and metabolic backgrounds of the moyamoya syndrome associated with atherosclerosis have not yet been investigated. We aimed to elucidate the hemodynamic and metabolic characteristics associated with the development of basal moyamoya-like vessels in moyamoya syndrome with atherosclerosis. Methods: Twenty-one patients with chronic unilateral atherosclerotic steno-occlusive lesions of the internal carotid artery or middle cerebral artery (MCA) were enrolled in the study. Based on the angiographic findings, the patients were classified into 2 groups: the moyamoya syndrome group (n = 7) and the non-moyamoya-syndrome group (n = 14). We conducted angiographic evaluations of the extent of the development of basal moyamoya-like vessels in the moyamoya syndrome group. The cerebral blood flow, cerebral metabolic rate of oxygen, oxygen extraction fraction (OEF) and cerebral blood volume were measured using PET in the ipsilateral MCA area in the patients and in normal controls (n = 6). Results: The OEF in the ipsilateral MCA area, except in the basal ganglia, was significantly higher in the moyamoya syndrome group than in the non-moyamoya-syndrome group (p < 0.001). The extent of the development of basal moyamoya-like vessels was closely correlated with the elevation of the OEF (r > 0.999, p < 0.001). Conclusion: The basal moyamoya-like vessels are evidence of misery perfusion in patients with unilateral chronic atherosclerotic steno-occlusive lesions of major cerebral artery trunks.

Middle Cerebral Artery Occlusion with Moyamoya-Like Vessels and Aneurysms

“…nese patients 2,[4][5][6][7] . Most patients with isolated MCA steno-occlusive disease do not have severe perfusion impairment unless they have another intracranial vascular occlusion 8,9 , Moreover, Kato et al 3 , by PET examinations, showed significant perfusion impairment in patients with occlusion of the middle cerebral artery and moyamoya phenomenon compared with patients without moyamoya vessels. In addition, Tanaka et al 8 demonstrated that patients with occluded MCA and moyamoya vessels had a poor leptomeningeal collateral network.…”

“…A moyamoya collateralization pattern can occur in isolated middle cerebral atherosclerotic stenosis 2 in response to poor perfusion 3 . Previously, only one clinical case was published, with ruptured aneurysm located in the collateral network in patients with moyamoya phenomenon secondary to middle cerebral artery occlusion.…”

Vascular remodeling after ischemic stroke: Mechanisms and therapeutic potentials

“…The development of these vessels is negatively correlated with the development of leptomeningeal collaterals from the PCA, and thus are positively correlated with the severity of the stenotic lesions in the major arterial trunks (Yamada et al, 1995). Despite the pathological effects of the development of Moyamoya-like vessels, they may exist as an attempt to compensate the insufficient collateral networks in the ipsilateral cortical area (Kato et al, 2008). …”

Blood Pressure Lowering with Valsartan Is Associated with Maintenance of Cerebral Blood Flow and Cerebral Perfusion Reserve in Hypertensive Patients with Cerebral Small Vessel Disease

“…We excluded patients with stenotic lesion in extracranial or intracranial large artery 24 to focus on cerebral hemodynamics in patients with cerebral small vessel disease. Our study clearly showed that blood pressure lowering with valsartan preserved CBF and CVR in the whole cerebrum, both gray and white matter, in patients with hypertension and lacunar infarcts.…”