Influence of improvement in frontal lobe hemodynamics on neurocognitive function in adult patients with moyamoya disease

Abstract

Background Adult moyamoya disease (MMD) often present with slight neurocognitive impairment. This impairment may result from frontal lobe hemodynamic insufficiency. Methods In current study, we performed revascularization surgery incorporating superficial temporal artery (STA)–anterior cerebral artery (ACA) direct bypass for 20 adults with MMD who had poor anterograde ACA flow (Group A), and pre- and postoperative results of neurocognitive tests were retrospectively analyzed. The comparative group (Group C) included 23 patients with unruptured aneurysms or brain tumors who underwent craniotomy and the same neurocognitive tests as patients with MMD. We calculated the compositive frontal lobe function index (CFFI) based on seven neurocognitive tests for each patient, and the difference between the pre- and postoperative CFFI values (CFFI Post − Pre) was compared between the two groups. Results Frontal perfusion was improved postoperatively in all cases of Group A. The CFFI Post − Pre was significantly higher in Group A than in Group C (0.23 ± 0.44 vs. −0.20 ± 0.32; p < 0.001). After adjusting for postoperative age, sex, preoperative non-verbal intelligence quotient and preoperative period of stress, Group A had a significantly higher CFFI Post − Pre than Group C in the multiple regression analysis (t value = 4.01; p < 0.001). Conclusion Improvement of frontal hemodynamics might be the key for improving neurocognitive dysfunction in adult MMD. The surgical indication and method should probably be considered not only from the perspective of stroke prevention, but also from the perspective of neurocognitive improvement or protection.