We report a case of a 52-year-old man who developed superficial and intraretinal hemorrhages, retinal edema and extensive cotton-wool patches, 2 weeks after the subconjuctival injection of gentamicin at the end of a 25 gauge sutureless vitrectomy (pars plana vitrectomy) for the repair of a, macula on, retinal detachment in his left eye. Fluorescein angiography revealed sharply defined zones of retinal vascular non-perfusion, mostly confined to the posterior pole and visual acuity deteriorated to 1/20 and remained unchanged during the follow up time. Our case illustrates the possibility of aminoglycoside toxicity after 25-gauge transconjunctaval sutureless PPV when the latter is administered subconjuctivally. It emphasizes that less toxic subconjuctival antibiotics may be considered for sutureless surgery, since if aminoglycoside toxicity occurs, the patient's vision may be permanently affected.