Rapidly progressive fatal bihemispheric infarction secondary to Moyamoya syndrome in association with Graves thyrotoxicosis

Abstract

Moyamoya syndrome is the secondary form of intracranial arterial occlusive diseases that produces collateral vessels from the base of brain. We report a case of Moyamoya syndrome developing in association with Graves thyrotoxicosis; as a result of its rapid progression and severe global ischemia, it was ultimately fatal. Because of the rarity of this association, we reviewed the literature in an attempt to establish possible demographic and clinical characteristics that may suggest putative mechanisms of pathogenesis.

Fig 1.

Axial cranial CT scans obtained with intravenous contrast enhancement (A, -B) show multiple areas of abnormal low attenuation, which are most dramatic within both frontal lobes as well as within the bilateral basal ganglia.

Fig 2.

The anteroposterior projections of bilateral internal carotid artery (ICA) angiography in early (A, right; -B, left) and late arterial phases (C, right; -D, left) and lateral projections of bilateral ICA angiography (E, right; -F, left) show nearly complete occlusion of the bilateral supraclinoid ICA as well as bilateral proximal segments of the ACAs and MCAs. Only minimal delay antegrade flows of the bilateral MCAs are noted. Collateral flows are seen from the posterior cerebral artery via the posterior choroidal plexus to the pericallosal artery.

Fig 3.

Magnified lateral projections of bilateral ICA angiography (A, right; -B, left) show only minimal collateral flows (arrows) from lenticulostriates over the base of brain, which reconstitute into the postocclusive or highly stenotic portions of the MCAs.