Influence of an Improvement in Frontal Lobe Hemodynamics on Neurocognitive Function in Adult Patients with Moyamoya Disease

In adults, moyamoya disease (MMD) often presents with slight neurocognitive impairment, which may result from frontal lobe hemodynamic insufficiency. In this study, we performed revascularization surgery by superficial temporal artery–anterior cerebral artery (ACA) direct bypass in 20 adults with MMD with poor anterograde ACA flow (Group M). The pre- and postoperative neurocognitive test results of these patients were retrospectively analyzed. The comparative group (Group C) included 23 patients with unruptured aneurysms or brain tumors who underwent craniotomy, as well as the same neurocognitive tests as Group M. We calculated the compositive frontal lobe function index (CFFI) based on the results of 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. Frontal perfusion improved postoperatively in all patients in Group M. The CFFI Post − Pre was significantly higher in Group M 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 M had a significantly higher CFFI Post − Pre than Group C in the multiple regression analysis (t value = 4.01; p < 0.001). Improving frontal lobe hemodynamics might be the key for improving neurocognitive dysfunction in adults with MMD. The surgical indication and method should be considered from the perspective of both stroke prevention and neurocognitive improvement or protection.