[Neuroretinal rim area (NRA) in early glaucoma].

The authors photographically measured the optic disks in 6 groups, namely, normal subjects with small cups and those with large cups, suspected glaucoma with small cups and those with large cups, primary open angle glaucoma (POAG) and low tension glaucoma (LTG). The effect of ocular optical magnification was corrected. The mean NRAs of POAG, LTG and suspected glaucoma with large cups were found less than those of the other 3 groups. In the normal subjects, an evident positive correlation existed between the cup area and the disk area, and the NRA was weakly correlated with the disk area. The diffuse and localized retinal nerve fiber layer defects were negatively correlated with the NRA significantly.