O27/263 Evaluation of relative risk of rupture of intracranial aneurysms by location: the case of ophthalmic aneurysms

Introduction Aneurysm location is a key element in predicting an intracranial aneurysm’s rupture risk. Ophthalmic aneurysms, superior hypophyseal/carotid cave aneurysms, internal carotid artery termination aneurysms are grouped together under the ‘internal carotid artery aneurysm’ label in studies evaluating the rupture risk of unruptured intracranial aneurysms. A shared experience suggests that ophthalmic aneurysms are under-represented in ruptured intracranial aneurysms. Aim of Study The purpose of this study is to evaluate specifically the relative risk of rupture of ophthalmic aneurysms. Methods This multicentre study compared the frequency of ophthalmic aneurysms in a prospective cohort of ruptured intracranial aneurysms admitted in 13 neuroradiology centres between January 2021 and March 2021 and the frequency of ophthalmic aneurysms in a retrospective cohort of unruptured intracranial aneurysms who underwent cerebral angiography at the same neuroradiology centres during the same time period. Results Six hundred and four intracranial aneurysms were included in this study (355 unruptured and 249 ruptured; median age 58-year-old, IQR [49; 65]; female 386/604 [63.9%]). Median aneurysm size was 5.4 mm (5.0 mm for unruptured intracranial aneurysms; 6.0 mm for ruptured intracranial aneurysms, p-value < 0.0001). Aneurysm shape was irregular for 37% unruptured aneurysms and 73% ruptured aneurysms (p-value < 0.0001). Ophthalmic aneurysms frequency was 15.2% of unruptured intracranial aneurysms (2nd most frequent aneurysm location) and 1.2% of ruptured intracranial aneurysms (2nd least frequent aneurysm location); OR 0.06798 (95% CI [0.2100; 0.2201], p-value < 0.0001). Conclusion Ophthalmic aneurysms have a low relative risk of rupture compared to other intracranial aneurysms. Disclosure of Interest Nothing to disclose.