Purpose of review: The review critically appraises the available evidence and current rationale for treating incidental intracranial aneurysms.
Recent findings: The rationale for treating incidental intracranial aneurysms uses comparisons between the so-called natural history, provided in a recent meta-analysis, and risks of treatments. Some risk factors for ruptures were identified (age >60, female sex, size >5 mm, posterior circulation aneurysms), but study quality is poor and relative risks are modest, of borderline statistical significance.
Summary: The medical literature cannot provide reliable numerical data of sufficient precision and quality to feed mathematical models of prediction of potential treatment benefits. Hence, the rationale fails to justify increasingly used treatments. A different approach using randomized trials is now in order.
Trial registration: ClinicalTrials.gov NCT00537134.