The Importance of Aneurysm Morphology and Perianeurysmal Environment in Aneurysmal Subdural Hematomas

Abstract

Aim: Aneurysmal subdural hematoma (anSDH) is an uncommon condition associated with significant mortality risk. This study focused on the relationship between morphology and the perianeurysmal environment by comparing aneurysm location and clinical outcomes. Material and Methods: A total of 486 patients with aneurysmal subarachnoid hemorrhage were retrospectively analyzed for accompanying subdural hematoma (SDH) cases. Demographic information, rebleeding, discharge, and 6 months of the modified Rankin scale scores (favorable and unfavorable) were recorded. The aneurysms were divided into 3 groups: internal carotid artery (ICA), anterior cerebral artery (ACA), and middle cerebral artery (MCA). Other parameters included aneurysm morphology, SDH width, intracerebral hematoma (ICH) volume, the presence of intraventricular hematoma, and distance to the subdural space. Results: Concomitant SDH was detected in 19 (3.9%) patients. Aneurysms were located in the ICA, 10 (52.6%); MCA, 8 (42.1%); and ACA, one (5.3%). The mean size was 9.5±4.3 mm, and there was a significant difference in aneurysm size between the ICA and MCA (p=0.025). In six supraclinoid aneurysms (posterior communicating and anterior choroidal arteries), the aneurysm dome was in the inferior lateral projection. No significant differences were observed between patients with favorable and unfavorable modified Rankin scale in terms of clinical and aneurysm morphological characteristics, except for increased ICH volume (p=0.020) and shift effects (p=0.030). Conclusion: The size and dome projection of ICA supraclinoid segment aneurysms may be important risk factors for SDH. We also believe that aneurysm localization may have a limited impact on clinical outcomes in the context of SDH.