[Comparison between binocular and monocular reading ability and its relation with central visual field sensitivity in glaucoma patients].

PURPOSE: To evaluate binocular and monocular reading ability in glaucoma patients with good visual acuity and to examine its relationship with central visual field sensitivity. METHODS: Glaucoma patients(35 individuals, mean +/- SD : 51.8 +/- 12.9 years) with a decimal visual acuity in each eye of >or=1.0, reading ability was tested both binocular and monocular using Japanese version of Minnesota Reading Acuity Chart (MNREAD-J). Reading ability parameters were calculated for maximum reading speed (MRS), critical print size (CPS), and reading acuity (RA). The results were compared with those of people with normal vision; differences in reading ability under varied testing conditions and correlations between visual field sensitivity and each parameter were examined. RESULTS: Under binocular reading conditions, MRS, CPS, and RA were decreased significantly in glaucoma patients compared with normal controls (p = 0.00044, p = 0.00004, p = 0.00028, respectively). Under monocular reading conditions, glaucoma patient MRS and RA were decreased significantly in comparison with normal controls (p=0.00155, p= 0.00142). In glaucoma patients undergoing binocular reading tests, MRS was greatest in the paracentral bottom right quadrant of the worse eye (r = 0.41709, p= 0.04447). The CPS decreased in proportion to the extent of the difference between both eyes in the mean deviation value and the visual field sensitivity of the paracentral bottom left (r = 0.40693, p = 0.02699 and r=0.41478, p=0.02384). RA improved in proportion to the extent of the difference between both eyes in the visual field sensitivity of the upper left (r = 0.33557, p=0.04799). CONCLUSION: In glaucoma patients, binocular reading is not necessarily useful in cases of visual field sensitivity differences.