Quantitative assessment of diffuse retinal nerve fiber layer atrophy using optical coherence tomography: diffuse atrophy imaging study.

Objective: To evaluate quantitatively the degree of diffuse retinal nerve fiber layer (RNFL) atrophy using Stratus optical coherence tomography (OCT).

Methods: Prospective, cross-sectional study. Methods: One hundred two eyes of 102 patients with diffuse RNFL atrophy and 102 healthy eyes of 102 age-matched subjects were enrolled in the Diffuse Atrophy Imaging Study. Methods: Two experienced observers graded RNFL photographs of diffuse RNFL atrophy eyes using a previously reported standardized protocol with a 4-level grading system. Readings were taken from the superior and inferior RNFL areas. The OCT-measured RNFL thickness parameters were compared among normal eyes and diffuse atrophy subgroups. Area under the receiver operating characteristic curves (AROCs) was calculated for various OCT RNFL parameters. Methods: Average and segmental (4 quadrants and 12 clock-hours) OCT-measured RNFL thicknesses and AROCs for various OCT parameters.

Results: For superior and inferior RNFL areas, diffuse atrophy grading by 2 observers agreed in 82.5% and 83.3% of cases, respectively, with a substantial agreement (kappa value = 0.760 [P < 0.001] and 0.777 [P < 0.001]). Significant differences were observed in RNFL thickness among normal and all diffuse atrophy subgroups, especially in the 7 and 11 o'clock sectors (P < 0.0001). The OCT RNFL thickness measurements decreased with increasing severity of RNFL damage. The 7 and 11 o'clock sectors showed the highest AROCs for discrimination of mild RNFL atrophy from normal eyes (0.972 and 0.979, respectively).

Conclusions: The OCT RNFL thickness parameters showed excellent quantitative correlation with the degree of diffuse RNFL atrophy. Our results suggest that Stratus OCT may serve as a useful adjunct in accurately and objectively assessing the degree of diffuse RNFL atrophy.