Background: Worldwide Meningioma Accounts for Approximately Up to 30% Of Primary Intracranial Tumor in Adult (1) and About 20%~30% Of Them Occurs in The Skull Base. Most Are Benign and Slow-Growing Tumors. (2) Although The Mainstay Treatment in Most of Cases Is Surgical Resection, Many Patients with Large and Critically Located Meningioma often Fail to Achieve Complete Resection Without Significant Neurologic Deficit Due To The Frequent Involvement Of Cavernous Sinus Or Cranial Nerve, Or Close Proximity To Optic Nerve Or Chiasm (3) The Progression Rate After Incomplete Resection Has Been Reported To Be 30% At 5 Years, 60% At 10 Years, And 90% At 15 Years. (4) The Success of Stereotactic Radiosurgery (SRS) Confirmed By Series With Excellent Long Term Results Has Led To A Shift In The Treatment Paradigms From Radical Surgery to a Combined Surgical/ Radio surgical Approach Or Even SRS As Primary Therapy. (5) Several Studies Concluded That Radiosurgery Is Able to Control Growth of Tumors In 80-100 % of Cases of Skull Base Meningioma (SBM). (6) However, In Cases Where the Tumor Is Large and Close to Critical Structures Like Optic Apparatus, Auditory Apparatus and Brain Stem, Physicians Face A Clinical Dilemma As High-Dose Radiation Exposure Can Lead To Neuritis And Irreversible Deterioration In Function. (7) So, The Concept Of Staged Volume SRS Was Emerged. The aim of This Study to Assess Safety Of Staged Volume Gamma Knife (GK) In Large Skull Base Benign Meningiomas With Size ≥ 10 Cc.