A Case of Moyamoya Disease with a Transient Neurologic Deterioration Associated with Subcortical Low Intensity on Fluid-Attenuated Inversion Recovery Magnetic Resonance Images After Bypass Surgery.

Abstract

Moyamoya disease often is treated by revascularization surgery. In this report, we are the first to describe a case of moyamoya disease that repeatedly showed a transient subcortical low intensity (SCLI) on fluid-attenuated inversion recovery (FLAIR) magnetic resonance images postoperatively. A 59-year-old woman presenting with repeated transient ischemia underwent right superficial temporal artery to middle cerebral artery anastomosis with encephalo-duro-myo-synangiosis. After the operation, the patient had a transient neurologic deterioration. Findings on magnetic resonance imaging were not particular apart from SCLI and sulcal hyperintensity on FLAIR images, but no abnormalities in cerebral blood flow on single-photon emission computed tomography with N-isopropyl [123I]-p-iodoamphetamine and no abnormalities on electroencephalogram were found. Symptoms improved in a few days, and SCLI on FLAIR images disappeared in a few months. Thereafter, when the left-sided bypass surgery was performed, similar findings occurred in the left cerebral hemisphere. The mechanisms of transient SCLI on FLAIR images remain unclear, but this finding appears to be associated with a postoperative transient neurologic deterioration.