Optimizing outcome in radiosurgery for spheno-orbital meningioma: the critical role of planning quality. Illustrative case

Abstract

BACKGROUND Spheno-orbital meningiomas (SOMs) pose significant challenges due to their proximity to critical structures, such as the optic nerve. This report underscores the pivotal role of meticulous planning in achieving favorable outcomes with Gamma Knife radiosurgery (GKRS). OBSERVATIONS A 54-year-old woman with a left SOM encasing the optic nerve underwent GKRS after being deemed unsuitable for surgery. The radiosurgical plan was meticulously tailored to balance effective tumor control with optic nerve sparing. A prescribed dose of 10 Gy at the 50% isodose line ensured a maximum optic nerve dose of 9.6 Gy, remaining within safe limits. Metrics such as high target coverage (0.96) and conformity (Paddick index: 0.83) highlighted the precision of the approach. A 12-year follow-up demonstrated stable tumor volume and preserved visual function without adverse effects, confirming the long-term efficacy and safety of this strategy. This case underscores the critical importance of comprehensive dose planning, particularly for perioptic lesions, where the therapeutic margin is narrow. LESSONS GKRS offers a minimally invasive alternative for SOMs ineligible for surgery, emphasizing the need for individualized treatment strategies. This case highlights how tailored radiosurgical planning can optimize outcomes, preserve function, and improve quality of life for patients with complex skull base tumors.