Rates and Patterns of Macular and Circumpapillary Retinal Nerve Fiber Layer Thinning in Preperimetric and Perimetric Glaucomatous Eyes

Purpose: To evaluate and compare the rates and patterns of macular and circumpapillary retinal nerve fiber layer (cRNFL) thickness thinning, assessed by spectral-domain optical coherence tomography (Cirrus SD-OCT), in eyes with preperimetric (PPG) and perimetric glaucoma (PG). Methods: The present retrospective cohort study included 127 eyes of 75 patients (PPG, 87; PG, 40) with a mean follow-up of 2.53 years. All patients underwent at least 4 SD-OCT examinations. Linear mixed effects models were used to evaluate the rates of changes in relevant cRNFL and macular parameters. Results: Overall, after adjusting for covariates including age, baseline OCT data, and visual field severity, thickness changes in the 6 o'clock (-2.325 mu m/y, cRNFL) and inferior outer sector (-2.879 mu m/y, macular) showed the highest progression rates among all evaluated parameters. When -0.26 and -0.42 mu m/y in average cRNFL and macular thickness changes were used as reference values for age-related physiological loss, 64.4% and 80.5% of PPG eyes and 60% and 70% of PG eyes, respectively, showed higher progression rates than these values. PG eyes showed significantly higher progression rates in the fovea and the inferior inner sector of the macula than did PPG eyes, although no progression rate of any cRNFL parameter differed between the 2 groups. Conclusions: PG and PPG eyes showed different rates and patterns in macular thickness progression when assessed by Cirrus SDOCT.