Estimating the Binocular Visual Field of Glaucoma Patients With an Adjustment for Ocular Dominance

To investigate whether it is possible to improve estimation of the binocular visual field (VF) using monocular sensitivities on a linear scale adjusted for ocular dominance. Monocular and binocular VF measurements were evaluated using the Humphrey Field Analyzer (HFA; 24-2 Swedish Interactive Threshold Algorithm standard program) in 60 eyes of 30 patients with open angle glaucoma. Ocular dominance was measured twice in each patient and the average value was used. Measured binocular sensitivity was then predicted based on monocular measurements using the "better sensitivity" integrated visual field (IVF) method, monocular sensitivity summation methods on the dB scale, linear scale (1/Lambert), and finally monocular sensitivity summation methods on the linear scale adjusted for the ocular dominance. The absolute prediction error with the linear scale summation method (mean ± SD: 3.11 ± 4.00) was significantly smaller than the IVF method (3.15 ± 4.09; P = 0.014). Further, the absolute prediction error for the ocular dominance adjusted method (3.10 ± 3.99) was significantly smaller than the nonadjusted linear scale summation method (P = 0.014). The absolute prediction error associated with the dB scale summation method was significantly larger than any other method (8.15 ± 5.06; P < 0.0001). The most accurate estimation of binocular sensitivity was achieved using the linear monocular sensitivity summation model adjusted for ocular dominance.