[Evaluation of stereometric parameters of optic disc and nerve fiber layer using HRT III. Report 1: reproducibility and intraobserver variability coefficients].

29 patients with initial primary open angle glaucoma were examined using Heidelberg retinal tomograph III (HRT III). In one visit 2 observers took 2 measurements. Intra- and interobserver errors (reproducibility and intraobserver variability coefficient) were calculated for 13 stereometric parameters of optic disc and retinal nerve fiber layer (RNFL). Rim area, cup depth (mean, maximum) and linear cup/disc ratios showed to be minimally variable. Cup area and volume, disc/cup area ratio were found to have greater variability. When performed by different observers (each entering his own contour) reproducibility was 1,4 fold lower compared with intraobserver reproducibility.