Early postoperative seizure after extracranial-intracranial revascularization for moyamoya disease and moyamoya syndrome: single centre post-revascularization moyamoya cohort study in Indonesia.

Early postoperative seizure after revascularization for moyamoya vasculopathy remains incompletely characterized, particularly in Indonesia. This study described the incidence and exploratory clinical and hemodynamic patterns associated with early postoperative seizure after extracranial-intracranial bypass in an Indonesian single center cohort. This single center retrospective cohort included moyamoya disease (MMD) or moyamoya syndrome (MMS) patients who underwent extracranial-intracranial revascularization. Early postoperative seizure was defined as a clinically documented new onset epileptic event occurring intraoperatively after bypass completion or within 14 days. Clinical and computed tomography perfusion (CTP) variables were compared between MMD and MMS and, within MMS, between seizure and non-seizure groups using descriptive exploratory analyses. Forty patients were analyzed, including 19 with MMD and 21 with MMS. Early postoperative seizure occurred exclusively in the MMS group (6/21, 29%) and was not observed in MMD (0/19; p = 0.021). Compared with MMS, MMD demonstrated larger pre-bypass infarct volume (14.48 ± 8.54 vs. 5.06 ± 5.52 mL; p = 0.005) and hypoperfusion volume (54.39 ± 33.07 vs. 27.26 ± 25.76 mL; p = 0.028). In paired CTP analysis, hypoperfusion volume decreased from 41.48 ± 27.78 to 26.06 ± 21.51 mL (p = 0.023), and infarct volume decreased from 10.27 ± 7.89 to 5.48 ± 4.16 mL (p = 0.040). Within MMS, patients with postoperative seizure were older (52.00 [41.75 to 55.00] vs. 35.00 [26.00 to 42.00] years; p = 0.014), more frequently presented with dysarthria (67% vs. 20%; p = 0.040) and monoparesis (50% vs. 0%; p = 0.015), and were more commonly classified as having suspected atherosclerotic vasculopathy (100% vs. 33.3%; p = 0.012). Follow up CTP demonstrated lower relative post-bypass CBV in the seizure group (0.31 [0.14 to 0.48] vs. 1.16 [0.68 to 1.22]; p = 0.026), although this finding was interpreted cautiously because postoperative imaging was not temporally aligned with seizure onset. In this exploratory Indonesian moyamoya cohort, early postoperative seizures were observed only in the MMS subgroup. Older age, baseline focal neurological deficits, and MMS related etiologic heterogeneity may be relevant to postoperative seizure susceptibility.