Radiation-associated intracranial aneurysms: A systematic review of clinical presentation, morphology, and treatment outcomes.

BackgroundRadiation-associated intracranial aneurysms (RAIs) are a rare but increasingly recognized late complication of cranial and cervical radiotherapy, particularly among long-term survivors of head and neck tumors. This study aims to provide a comprehensive review of the clinical, anatomical, and therapeutic characteristics of RAIs.MethodsWe conducted a systematic review of published RAI cases (1984-2024), collecting data on patient demographics, oncologic history, aneurysm morphology and location, latency from radiotherapy, clinical presentation, and treatment outcomes. The review followed Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines.ResultsA total of 103 patients with 142 intracranial aneurysms were included. The mean latency between radiotherapy and aneurysm diagnosis was 11.3 years (range: 2-21 years). The mean age at radiotherapy was 36.7 years (range: 4 months to 79 years), and the mean age at aneurysm diagnosis was 47.8 years (range: 6-90 years). Aneurysms were most commonly located in the internal carotid artery (32%) and posterior circulation (23%). Morphologically, 45.1% were dissecting or nonsaccular. Half of the aneurysms presented with subarachnoid hemorrhage. Approximately 65% underwent treatment, with about two-thirds managed via endovascular approaches-primarily coiling and stent-assisted coiling. Adequate occlusion was achieved in 66% of aneurysms overall, with an even higher rate of complete/near-complete occlusion-73.1%-among endovascularly treated aneurysms, compared to 48.5% for those treated surgically. The mean radiological follow-up period was 19.5 months.ConclusionRadiation-associated intracranial aneurysms are rare vascular lesions with distinct anatomical and clinical features. Early recognition and sustained long-term monitoring are crucial to enable timely intervention. Further research is needed to establish evidence-based strategies for screening and managing this high-risk population.