Influence of topical betaxolol and timolol on visual field in Japanese open-angle glaucoma patients

Purpose: To assess the effects of topical betaxolol and timolol on the visual field in Japanese open-angle glaucoma (OAG) patients. Methods: This study was a multicenter, 2-year, prospective, randomized and double-masked study. Tests using the Humphrey 30-2 perimeter program were conducted every 6 months and the data of 95 patients were analyzed using regression analysis. Estimated regression coefficients for mean deviation (MD), corrected pattern standard deviation (CPSD), and total deviation (TD) values clustered into 15 sectors were obtained for each treatment group. Results: Estimated slopes (dB/year) for MD and CPSD showed no significant difference from zero in either group. However, in the betaxolol group, estimated slopes (dB/year) for two adjacent sectors in the inferior arcuate area were significantly positive (P=.0135,.0116) while in the timolol group, no significant difference from zero was seen in any of the sectors. IOP changes from baseline in the timolol group were greater than in the betaxolol group, although no statistical significance was seen at any of the examination times. Conclusion: MD and CPSD showed no significant change in either group. In the betaxolol group, however, a significant trend in improvement of visual field performance was seen in the inferior arcuate subfield. Timolol reduced IOP more effectively than betaxolol in OAG patients.