Association between Cognitive Decline and Altered Cerebral Perfusion in Adults with Moyamoya Disease after Revascularization

Abstract

<b><i>Introduction:</i></b> Certain studies have observed that patients with moyamoya disease (MMD) have cognitive decline after revascularization. Thus, this study analyzed the relationship between cognitive decline and altered cerebral perfusion after revascularization. <b><i>Methods:</i></b> Here, 313 adult patients with MMD underwent single unilateral revascularization. First, cognitive function was scored using a Mini-Mental Scale (MMSE) and Montreal cognitive function scale (MoCA) before and 3 months after the operation (superficial temporal artery-middle cerebral artery anastomosis with encephalo-myo-synangiosis). Then, computed tomography perfusion was performed before and 1 week after the operation to assess the cerebral perfusion. <b><i>Results:</i></b> Our data showed that cognitive function decreased in 55 cases (17.6%) after revascularization. Furthermore, the incidence of cerebral hyperperfusion (CHP) was significantly higher in the cognitive decline group (49/55) than in the cognitive nondecline group (89.1% vs. 5.4%, <i>p</i> &#x3c; 0.001). Results also showed that although all 55 patients had postoperative cognitive decline, 47 experienced relative cerebral blood flow (CBF) decrease at a relatively distant area of the anastomosis compared with that before the operation, which was significantly higher than in patients without cognitive decline (85.5% vs. 1.94%, <i>p</i> &#x3c; 0.001). In addition, 41 patients had a simultaneous occurrence of local CHP and paradoxical CBF decrease at a relatively distant anastomosis area, which indicated the incident of watershed shift (WS). As observed, WS occurred in 74.5% of patients with cognitive decline, significantly higher than in patients without cognitive decline (74.5% vs. 0%, <i>p</i> &#x3c; 0.0001). Through multiple logistic regression analysis, WS was also observed to be a strong independent risk factor for predicting postoperative cognitive decline 3 months after revascularization (odds ratio 17.780, 95% confidence interval 1.668–18.564; <i>p</i> = 0.017). <b><i>Conclusion:</i></b> Therefore, cognitive decline in patients with MMD after revascularization is related to WS, leading to an uneven distribution of CBF.