Review of current treatment modalities and clinical outcome of giant saccular aneurysms of the basilar apex

Introduction: Giant aneurysms of the basilar apex represent formidable challenges as the high rupture rate of untreated lesions must be balanced against the technical complexity and potential morbidity of intervention. Research question: Review of treatment modalities and outcomes of patients harboring giant (>2.5 cm) basilar apex saccular aneurysms, in an effort to refine treatment decision-making. Material and methods: A systematic literature review through the PubMed and Scopus databases was performed according to the PRISMA guidelines to identify cases of giant basilar apex saccular aneurysms treated either microsurgically or endovascularly. Patients' demographics, aneurysm size, preoperative and postoperative neurologic status, angiographic and clinical outcomes as well as follow-up information were obtained. Results: Data from 32 studies fulfilling the inclusion criteria, including 49 patients (32 treated surgically and 17 endovascularly) was obtained. Mean patient age at presentation was 51.69 years, with a male-to-female ratio of 1:2. Mean maximum aneurysm diameter was 30.57 mm. A favorable outcome (mRS 0-2) was reported on 70.6% of endovascular and 56.3% of open surgical cases. Complete aneurysm occlusion was achieved in 55.6% of the open and 23.5% of the endovascular cases. Death rate was 33% for endovascular and 15.6% for open cases; the higher mortality of endovascular treatment is mainly attributed to the mass effect from continued brainstem compression after treatment. Discussion and conclusion: Higher rates of complete occlusion but higher morbidity are associated with microsurgery compared to endovascular modalities. Severe, clinically apparent brainstem mass effect may require decompression associated with microsurgery, when technically feasible.