LAUSR

BACKGROUND Balloon-assisted coil embolization (BAC) is one of the endovascular treatment (EVT). However, it may be associated with increased complications and thromboembolic events when compared to other coiling techniques. In this study, we compared the clinical outcomes of EVT (simple coiling, stent-assisted coil embolization (SAC), and BAC) in patients with unruptured intracranial aneurysms (UIAs) at the internal carotid artery (ICA) and assessed the risk factors that could cause cerebral infarction in patients who underwent BACs. METHODS We retrospectively reviewed the records of 528 patients with 544 aneurysms who underwent endovascular treatment for UIAs between January 2013 and November 2019. The demographic features, clinical information, balloon inflation time, fetal posterior cerebral artery, anterior cerebral artery (ACA) variants, and angiographic results were analyzed to reveal the risk factors for cerebral infarction. RESULTS There were no significant differences among the three groups in terms of general characteristics. However, 14/39 patients who underwent BAC showed a significantly higher incidence of cerebral infarction in the diffusion MRI compared to the SAC (37/238) and simple coiling (21/267) groups (p<0.001). There was no significant difference between the ACA variants (normal vs. hypoplasia or aplasia) and cerebral infarction in the simple coiling and the SAC groups, but the proportion of aplasia or hypoplasia in the BAC (p=0.001) group was significantly higher. CONCLUSIONS There is a significant association between anatomic ACA variants and cerebral infarction occurrence after BAC. Therefore, identifying the variant of the anatomic ACA by digital subtraction angiography would help to predict cerebral infarction after BAC.