Morphological Risk Factors for Rupture of Small (<7 mm) Posterior Communicating Artery Aneurysms

Background The management of small, unruptured intracranial aneurysms is still controversial. Given the distinctive natural history of aneurysm at different locations, location-specific analysis might be a reasonable approach. This study aimed to investigate morphological discriminators for rupture status by focusing on only posterior communicating artery (PcomA) aneurysms smaller than 7 mm. Methods In 108 small PcomA aneurysms (68 ruptured, 40 unruptured), clinical and morphological characteristics were compared between the ruptured and unruptured groups. Multivariate logistic regression analysis was performed to determine the independent predictors for the rupture status of small PcomA aneurysms. Results None of the clinical characteristics were significantly different between the ruptured and unruptured groups ( P > 0.05). The ruptured group revealed a significantly larger size ( P = 0.009), aspect ratio ( P = 0.009), size ratio ( P = 0.002), dome-to-neck ratio ( P = 0.002), inflow angle ( P