Current Treatment Paradigms for Giant Thrombotic Intracranial Aneurysms: A Systematic Review

Objective: Giant thrombosed intracranial aneurysms (GTIAs) are aneurysmal dilatations containing partial or complete intraluminal thrombus. Representing approximately 2–5% of intracranial aneurysms, GTIAs present diagnostic and therapeutic challenges. Optimal management remains controversial and may involve microsurgical, endovascular, or hybrid strategies. Methods: A systematic review was performed in accordance with PRISMA guidelines using PubMed and Embase to identify relevant studies published between January 2000 and August 2025. Eligible studies reported clinical, anatomical, or treatment-related data for patients with GTIAs. Extracted variables included patient demographics, aneurysm characteristics, treatment modality, and outcomes. Data were standardized and analyzed using Python. Complication and recurrence rates were pooled in subsets of studies reporting explicit event counts; comparisons between treatment modalities were assessed using chi-square analysis. Results: In total, 101 studies including 536 patients met our criteria. Mean patient age was 50.2 years. Most aneurysms arose from the anterior circulation (88.2%) involving the internal carotid artery (46.6%) and middle cerebral artery (39.9%). The unweighted mean aneurysm diameter was 39.0 mm, with a patient-weighted mean of 24.3 mm. Hybrid treatment strategies were most frequently reported (62.7%), followed by endovascular (23.3%) and microsurgical (14.0%) approaches. Among studies reporting explicit counts, the pooled complication rate was 17.0% and the recurrence rate was 21.0%. Complication rates did not differ significantly between treatment modalities (p = 0.48), whereas recurrence differed significantly (p = 0.00013). Conclusions: Management of GTIAs remains heterogeneous, with increasing reliance on multimodal and hybrid treatment strategies. However, inconsistent outcome reporting and the predominance of retrospective studies limit definitive comparisons between treatment modalities.