Abstract
PURPOSE: To assess the long-term effects of focal/grid laser treatment on the central visual field in subjects with clinically significant diabetic macular oedema (CSMO). METHODS: Twenty-six subjects with CSMO were included in the study. Fundus photography, assessment of retinal thickness by time-domain optical coherence tomography (OCT), measurement of visual acuity (VA) and standard automated perimetry of the central 10° of the visual field were performed at baseline before focal/grid laser treatment and thereafter at four follow-up visits 6 months apart, when the laser treatment was also repeated in subjects with persistent oedema. Changes in VA and retinal thickness between baseline and study end at 24-month follow-up were calculated. Trends in changes in the visual field were assessed by linear regression of number of significantly depressed test points over time. RESULTS: On average after the laser treatment, retinal thickness decreased by 17% and VA decreased by three letters. In most eyes, visual fields were stable over time: the mean of the trend slopes (0.05 points/month) did not differ significantly from 0 (p = 0.63). The number of depressed test points at follow-up was not correlated with either the total number of laser effects or the number of laser sessions. CONCLUSION: Focal/grid laser treatment for CSMO did not affect retinal sensitivity in the central visual field in the subjects included in this 2-year follow-up study.