Effects of the relative positioning between the disc-fovea angle and localized optic disc defects on the 10-2 visual field results in glaucoma

Purpose To investigate the effects of the foveal position relative to the optic disc on the 10-2 visual field (VF) results of patients with glaucoma with localized inferotemporal (IT) neuroretinal rim defects. Design Cross-sectional study. Participants Fifty-seven eyes of 35 patients with open-angle glaucoma (OAG) were included and divided into 2 groups based on the presence (18 eyes) or not (39 eyes) of IT neuroretinal rim defects. Methods Three different parameters obtained from a spectral-domain (SD) OCT (disc-fovea angle [DFA], fovea vertical deviation [FVD] from midline, and the angular difference between the IT neuroretinal rim defect border and the DFA [defect's angular difference [DAD]) were tested for their relationship with four 10-2 VF sectors: superior hemifield, superior edge, nasal edge, and superonasal arcuate. These relationships were tested with regression analyses with linear mixed-effects models and random intercepts. Main Outcome Measures Influences of DFA, FVD, and DAD on 10-2 VF sectors. Results Mean (± standard deviation [SD]) values of DFA, FVD, and DAD were −5.05°±4.40°, −1346.6±1609.0 μm, and 43.30°±17.33°, respectively. After adjustment for multiple comparisons, both FVD and DAD, but not DFA, were significantly associated with the severity of defects on the predefined VF sectors. Larger DAD values (third tertile: 54°–77°) showed higher coefficient estimate for the nasal edge sector sensitivities. Conclusions The vertical foveal location and its position relative to the IT neuroretinal rim defects were associated with loss of sensitivity at 10-2 VF locations in the superior hemifield. This association was significant but weak and was not seen using other conventional parameters that describe the foveal position relative to the optic disc on SD OCT.