2026 Proffered Presentations
S002: ANEURYSM GEOMETRY AND LOCATION ARE ASSOCIATED WITH RUPTURE STATUS IN VERY SMALL ANEURYSMS
David Bonda, MD1; Danielle Golub2; Thomas Link, MD2; Athos Patsalides, MD2; Daniele Starnoni, MD2; Amir R Dehdashti, MD2; 1Cedars Sinai; 2Northwell Health
Introduction: It is well known that the majority of ruptured aneurysms are small <7mm. Understanding risk factors associated with aneurysm rupture is important when deciding treatment paradigms. We sought to identify factors associated with rupture status in very small aneurysms <4mm.
Methods: A retrospective chart review of patients with small aneurysms <4mm evaluated at our brain aneurysm center between 2013-2019 was done. Factors including aneurysm location, rupture status, medical history, and aneurysm geometry were collected. Aneurysms were placed into two cohorts, ruptured vs unruptured, and factors associated with rupture status were assessed.
Results: A total of 209 aneurysms with a maximum diameter of <4mm were identified. Mean aneurysm diameter was 2.53mm. A total of 65% of aneurysms were ruptured and most of the patients (75%) were female. Aneurysm aspect ratio and dome to neck ratio were significantly different between both groups (P=0.02 and P=0.00). Ruptured aneurysms had a higher aspect ratio of 1.23 vs. 1.09 and a higher dome to neck ratio of 1.1 vs. 0.94. Height, width and neck diameters were not significantly different between the two groups. Average height was 2.73mm vs 2.84 mm (P=0.33), average width was 2.4mm vs 2.6mm (P=0.01), and average neck was 2.73 vs 2.49 (P=0.12). Aneurysm morphology as defined by saccular vs irregular was also associated with rupture status (P=0.004). Finally, aneurysms of the anterior communicating artery, posterior communicating artery, and in the posterior circulation were also more frequent in the ruptured group when compared to middle cerebral artery, pericallosal, and internal carotid artery aneurysms (P=0.00).
Conclusions: Aneurysm geometry, morphology, and location are associated with rupture status in very small <4mm aneurysms. This may help develop risk models to better decide treatment paradigms for very small aneurysms.