Objective:To evaluate the effect of radial optic neurotomy on visual acuity(VA)and foveal thickness in patients with hemicentral retinal vein occlusion.Methods:A prospective noncomparative case series of 13 eyes in 13 patients with hemicentral retinal vein occlusion and a preoperative VA of 20/60 or less from a total of 232 retinal vein occlusions diagnosed.All patients underwent pars plana vitrectomy,posterior hyaloid dissection,and radial optic neurotomy at the nasal border of the optic disc.Results:Visual acuity and macular thickness were measured with optical coherence tomography.Nine patients(69.2%)gained 2 ormore Snellen lines of vision,and in 4 patients(30.8%)VA improved by 4 ormore Snellen lines(median visual acuity,20/50;mean VA,20/45;P<.01)(average gain,2.7 Snellen lines).The decrease in foveal thickness was statistically significant(P<.01)(median decrease,297 μ m).Final VA was statistically related to decreased macular thickness at optical coherence tomography(P=.03;ρ =-0.62).Retinochoroidal shunts developed in 6 patients(46.1%)at the radial optic neurotomy site.No surgical complications were observed.Conclusions:Radial optic neurotomy seems to be a potential treatment in selected patients with hemicentral retinal vein occlusion,probably because of the more rapid appearance of retinochorioretinal collateral vessels,which promote faster resolution of macular edema. Objective: To evaluate the effect of radial optic neurotomy on visual acuity (VA) and foveal thickness in patients with hemicentral retinal vein occlusion. Methods: A prospective noncomparative case series of 13 eyes in 13 patients with hemicentral retinal vein occlusion and a preoperative VA of 20/60 or less from a total of 232 retinal vein occlusions diagnosed. All patients underwent pars plana vitrectomy, posterior hyaloid dissection, and radial optic neurotomy at the nasal border of the optic disc. Results: Visual acuity and macular thickness were measured with optical coherence tomography.Nine patients (69.2%) gained 2 ormore Snellen lines of vision, and in 4 patients (30.8%) VA improved by 4 ormore Snellen lines (median visual acuity, 20/50; mean VA, 20/45; P < .01) (average gain, 2.7 Snellen lines). The decrease in foveal thickness was significantly significant (P <.01) (median decrease, 297 μ m). Final VA was statistically related to decreased macular thickness at optical coherence tomography = .03; ρ = -0. 62). Retinochoroidal shunts developed in 6 patients (46.1%) at the radial optic neurotomy site. Non-surgical complications were observed. Conclusions: Radial optic neurotomy seems to be a potential treatment in selected patients with hemicentral retinal vein occlusion, probably because of the more rapid appearance of retinochorioretinal collateral vessels, which promote faster resolution of macular edema.