Prevention of visual field defect after macular hole surgery by passing air used for fluid-air exchange through water

PURPOSE: To evaluate the effect on peripheral visual field defects occurring after macular hole surgery of passing air that is used for fluid-air exchange through water before infusion to the eye. METHODS: We used Goldmann perimetry to measure the visual fields of patients who underwent vitrectomy to manage idiopathic full-thickness macular holes using either room air or humidified air for fluid-air exchange. We retrospectively studied visual fields measured in 39 patients (group 1) who underwent vitrectomy without humidification of air and prospectively studied visual fields measured in 33 patients (group 2) who consecutively underwent vitrectomy with humidified air for fluid-air exchange. RESULTS: In group 1, nine patients (23%) had peripheral visual field defects, most often located in the inferior or inferotemporal quadrant. No patients (0%) in group 2 had a visual field defect after vitrectomy. The difference between groups 1 and 2 in the proportion of patients with visual field defects after vitrectomy was statistically significant (P = .003). CONCLUSIONS: Passing air used for fluid-air exchange through water seems to prevent visual field defects after vitrectomy for macular hole surgery. Visual field defects that occur after room air is used may result from desiccation of the retina by room air. (C) 1999 by Elsevier Science Inc. All rights reserved.