The risk of seizures during the in-hospital admission for surgical or endovascular treatment of unruptured intracranial aneurysms

Few studies detail the risk of in-hospital seizures following elective surgical or endovascular treatment of unruptured intracranial aneurysms (UIA). We compared the peri-procedural seizure incidence for clipping and coiling of UIA. A retrospective cohort study using the Australian National Hospital Morbidity Database from 1998 to 2008 was conducted. Treatment modalities were compared for the combined primary end point related to seizure. Putative risk factors were investigated with univariate and multivariate logistic regression analysis to identify independent predictors of outcome. A total of 5922 hospitalisations for UIA (3098 clipping, 2824 coiling) were identified. Overall, surgery was associated with a 2.7% (95% confidence interval [CI] 2.2–3.4) incidence of peri-operative seizures, compared to a 0.6% (95% CI 0.4–1.0) incidence following endovascular treatment (adjusted odds ratio [OR] 4.40; 95% CI 2.64–7.33; p < 0.001). The incidences of seizures declined over the 11 year study period in both treatment groups, from 4.2% to 2.0% for surgery and from 2.8% to 0.3% for endovascular. Haemorrhagic complication with intracerebral haemorrhage predicted occurrence of a seizure (OR 3.41; 95% CI 1.20–9.66; p = 0.021), whereas endovascular coiling was associated with a better seizure outcome (OR 0.23; 95% CI 0.14–0.39; p < 0.001). Overall, elective surgical treatment of UIA is associated with a higher risk of seizure occurrence compared to endovascular coiling. Contrary to conventional thinking, the risk of seizures following endovascular treatment is not entirely absent. Current recommendations must be considered in relation to the issue of driving after elective intracranial aneurysm treatment.