gms | German Medical Science

Objective: Cerebral infarction (CI) is a potential complication of microsurgical clipping of intracranial aneurysms and can lead to severe morbidity and mortality. The association between aneurysm morphology and CI has not yet been analysed in detail. The objective of this study was to evaluate the impact of aneurysm shape and aneurysm neck configuration on CI after aneurysm surgery.

Methods: This is a retrospective, single-center analysis of consecutive patients with ruptured and unruptured aneurysms that were treated by microsurgical clipping between 2010 and 2018. Based on three-dimensional reconstructions from preoperative computed tomography (CT) and digital subtraction angiography, aneurysm shape was categorized as regular (single-sac) and irregular (daughter sac/lobulated). Likewise, the aneurysm neck was defined to be regular or irregular (protrusion of the aneurysm wall at the neck). Postoperative CT scans were used to assess CI. We analysed both symptomatic and asymptomatic infarction. Morphological and procedure-related risk factors for CI were identified by using univariate and bivariate logistic regression analyses.

Results: The study population consisted of 243 patients with 252 aneurysms (148 ruptured, 104 unruptured). Aneurysms were defined to have an irregular shape in 50.8% and an irregular neck in 33.0%. The overall and symptomatic CI rates were 17.1% and 9.9%, respectively. The CI rate was higher among ruptured aneurysms (20.9%) than among unruptured aneurysms (11.5%, p=0.05). CI occurred tendentially more often in aneurysms with irregular shape (23.2% vs. 10.3%, p=0.08). Moreover, aneurysms with an irregular neck had a higher CI rate (37.5%) than aneurysms with a regular neck (10.1%, p<0.01). Irregular neck configuration was further associated with an increased rate of intraoperative rupture (31.3% vs. 14.4%, p<0.01) and temporary parent artery occlusion (35.9% vs. 21.3%, p=0.04). In the multivariate analysis, irregular neck configuration remained as an independent risk factor for CI (OR=4.1, 95% CI: 1.9–9.1, p<0.01), while the association between aneurysm shape and CI was not significant (p=0.9).

Conclusion: In the current study, we identified irregular aneurysm neck configuration as independent risk factor for CI during microsurgical clipping of both ruptured and unruptured aneurysms.