Neuropsychological functioning of people with Moyamoya disease

Abstract

Moyamoya Disease (MMD) is a chronic, idiopathic, progressive cerebrovascular condition causing the abnormal narrowing or obstruction of cranial arteries around the Circle of Willis, causing a mesh of compensatory collateral capillaries to develop across the sites manifesting as “a hazy puff of smoke” (known as “Moyamoya” in Japanese). Patients are at risk of suffering from cardiovascular accidents that often prompt them to undergo surgery. Individuals with Moyamoya Disease often suffer from neuropsychological impairments in executive functions, complex attention and memory, currently understood to be related to prolonged disruption of blood flow due to the abnormal arterial growth. It remained unclear by far whether such impairments are reversible through surgical revascularization. The current study investigated patterns of neuropsychological changes upon surgical revascularization, attempting to take into account practice effects with a matched healthy comparison group. Associated with the rarity of disease and thus inevitably small sample size (n=11) of MMD patients, no conclusion based on inferential statistics could be obtained in this study. However, descriptive data pointed towards the direction that memory functions showed more reversibility than other cognitive domains which was consistent with current neuroscientific understanding of exclusively substantial adult neurogenesis of hippocampus. Executive functions and complex attention appeared to receive no benefit from surgery.