Document resource
Background Evidence regarding the clinical course of unruptured giant intracranial aneurysms (GIAs) after conservative management (CON), microsurgical treatment (SURG) or endovascular treatment (EVT) remains limited. We aimed to assess mortality, functional outcome, symptom course and retreatment rates after different management strategies.Methods In this prospective, multinational registry, patients with unruptured GIAs treated at 37 neurovascular centres between 2008 and 2018 were included. Outcomes after CON, EVT or SURG were analysed with standardised 3-year follow-up. The study is registered at ClinicalTrials.gov.Results We included 339 patients of whom 22.7% received CON, 42.8% EVT and 34.5% SURG. Three-year survival was 64.0% (95% CI 53.73% to 76.20%) in the CON group, 82.0% (95% CI 75.42% to 89.17%) in the EVT group and 93.5% (95% CI 88.91% to 98.28%) in the SURG group (p<0.001). Favourable neurological outcome (modified Rankin Scale 0–2) declined to 53.0%, 66.9% and 75.7% in the CON, EVT and SURG groups, respectively (p<0.01). Symptom improvement at 3 years occurred in 10.3% of CON, 22.1% of EVT and 11.1% of SURG patients, while deterioration was observed in 7.7%, 8.5% and 15.8%, respectively. Retreatment was required in 22.8% of EVT patients and 6.2% of SURG patients (p<0.01).Conclusions EVT and SURG were associated with significantly improved survival and functional outcomes compared with conservative management of unruptured GIAs. In patients eligible for intervention, both treatment modalities represent reasonable and effective options, with a high proportion of patients achieving favourable clinical outcomes.Trial registration number NCT02066493.