RESUMO
PURPOSE: To determine whether colour vision improves following reduction of intraocular pressure (IOP) in glaucoma patients. METHODS: The medical records of 29 glaucoma patients (41 eyes) were reviewed. Inclusion criteria required subjects to have made more than four visits to the Glaucoma Service Laboratory and to undergo a thorough eye examination including a Farnsworth-Munsell 100-hue colour vision test and Goldmann tonometry before and after pressure lowering. Colour vision parameters of total error score (TES), yellow-blue score (YBS) and red-green score (RGS) were measured. The study group consisted of 21 eyes of glaucoma patients who underwent uncomplicated trabeculectomy with an IOP reduction of >/= 20% from baseline. The control group consisted of 21 eyes of glaucoma patients matched for age and colour vision, who received medication and/or underwent surgery with a post-intervention IOP reduction of < 20% from baseline. The primary outcome was a comparison of pre- and post-intervention colour vision parameters between the two groups. RESULTS: There was a statistically significant improvement in TES (43 +/- 44, p < 0.001), RGS (19 +/- 27, p = 0.0077) and YBS (23 +/- 29, p = 0.0007) in the study group compared with the control group. The improvement in TES (r = 0.52, p < 0.001), RGS (r = 0.55, p < 0.001) and YBS (r = 0.40, p = 0.008) was correlated with the percentage of IOP reduction. There was no statistically significant difference between improvement in Y-B and R-G scores in the study group. CONCLUSION: Intraocular pressure reduction of >/= 20% post-trabeculectomy was associated with an improvement in colour vision. Colour vision tests may be useful as an adjunctive outcome measure for therapeutic interventions.