Abstract
Gamma Knife radiosurgery (GKRS) is a well-established, minimally invasive treatment modality for meningiomas, offering high rates of tumor control and symptom relief. However, clinical outcomes are influenced by tumor anatomical location, necessitating a comprehensive evaluation of its effectiveness across infratentorial and supratentorial regions. A systematic review was conducted by following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, including clinical trials and observational studies evaluating GKRS outcomes in meningiomas. Studies were included if they explicitly stratified results by anatomical location and reported clinical outcomes such as tumor control, progression-free survival (PFS), symptom relief, and complications. The ROBINS-I (Risk of Bias in Non-randomized Studies - of Interventions) tool was used to assess the risk of bias. Data were synthesized qualitatively, and outcomes were compared between anatomical locations. Eighteen studies involving 2,257 patients were included. Overall five-year tumor control rates were high for both infratentorial (93.2%) and supratentorial (91.4%) meningiomas. Infratentorial tumors showed slightly better control rates but higher complication rates, including peritumoral edema and cranial nerve deficits due to proximity to critical structures. Supratentorial meningiomas demonstrated favorable long-term outcomes with fewer complications. Infratentorial tumors achieve excellent control but present higher risks of complications, partly due to their proximity to critical structures and the need for precise dosimetry in typically smaller tumors. In contrast, supratentorial tumors, often larger and more accessible, benefit from fewer adverse events and comparable long-term outcomes. Tumor size, along with anatomical location, plays a key role in radiosurgical planning and complication risk. Future research should focus on prospective studies to refine treatment protocols and enhance outcomes in atypical and anaplastic meningiomas.