Causes of visual field defects after vitrectomy]

PURPOSE: An inferotemporal visual field defect sometimes occurs following vitreous surgery for idiopathic macular hole. There is a possibility that this visual field defect is due to damage to the superonasal retina by fluid or air irrigation through an inferonasal infusion port. We tested this hypothesis by placing the infusion port in the inferonasal sector during vitreous surgery. CASES AND METHOD: We performed vitreous surgery on 31 eyes with idiopathic macular hole. The infusion port was placed in the inferonasal sector. The vitreous cavity was replanced either by 20% SF6 or 12% C3F8. We did not abrade the retinal pigment epithelium within the hole. The visual field was assessed before and 1 month after surgery using a Goldmann perimeter. FINDINGS: Three eyes developed a wedge-shaped visual field defect in the inferonasal sector. No visual field defect developed in the other 28 eyes. CONCLUSION: The findings show that visual field defect following surgery for idiopathic macular hole is dependent upon the site of the infusion port. We presume that the visual field defect is consequent to retinal damage caused by the flow of air or fluid during surgery.