Idiopathic macular hole is a full-thickness defect of the neurosensory retina which can be treated by three-port vitrectomy. The pathogenesis is not understood completely, but tangential traction of the vitreous and retinal surface may cause opening of a macular hole. Vitrectomy with or without internal limiting membrane peeling may relieve the tangential traction. The anatomical success rate is 58-85% without internal limiting membrane peeling and 88-95% with internal limiting membrane peeling. A high success rate was achieved in patients who had surgery within 6 months of the onset of symptoms. Among the complications were retinal breaks, retinal detachment, retinal pigment epitheliopathy, and visual field defect, the most serious complication. Temporal visual field defect can be eliminated by reducing the fluid-gas exchange time and stabilizing intraocular pressure during surgery. Nasal visual field defect can be eliminated by the use of a lower concentration of indocyanine green or of triamcinolone acetonide instead of indocyanine green.