"Neural capacity" index correlates with neuroretinal rim area of glaucomatous eyes better than light sensitivity
We compared the relationship between the neuroretinal rim area and the neural capacity (NC) index of high-pass resolution perimetry (HRP) and the differential light sensitivity (DLS) of a Humphrey Field Analyzer (HFA). Subjects were 40 eyes of 27 normal-tension glaucoma (NTG) patients. The total rim area and the area of its temporal, superior, nasal, and inferior quadrants were determined with a confocal laser tomographic scanner. Mean local NC (MLNC) was calculated using the resolution thresholds corresponding to the quadrant. Mean local DLS (MLDLS) was calculated using the data of program 30-2 of HFA. In a total of 40 eyes, NC and mean deviation were significantly correlated with the total rim area (rs = 0.422, p < 0.01: rs = 0.360, p < 0.05, respectively). NC was also significantly correlated with the total rim area in 19 eyes with early visual field changes, but not in 21 eyes with advanced changes. MLNC was significantly correlated with the superior and inferior rim areas, and MLDLS was significantly correlated with the inferior rim area. These results indicate that indices of HRP may relate to glaucomatous optic disc changes better than those of HFA in NTG, especially in patients with early visual field defects.