Improvement in colour vision parameters following successful trabeculectomy

. 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.