This study compared photon radiosurgery plans and IMPT plans to the clinically delivered photon treatment plans of 24 vestibular schwannoma patients to investigate the potential of dose reduction to cochlear. Photon plans were generated with Cyberknife with no PTV margin. Proton plans were generated with three or nine-beam arrangements and 3 % range robustness. A reduction of cochlear Dmean > 1.5 Gy(RBE) could be achieved in 11/24 Cyberknife plans, 4/24 three-beam proton plans and 6/24 nine-beam proton plans. The authors concluded that with the set-up robustness, proton therapy was capable of providing lower dose to organs at risk located distant to the tumor, but not for organs adjacent to it. Consequently, photon plans provided better cochlear sparing than proton plans.