Myelinated Retinal Nerve Fiber Progression in a 10-Year Follow-Up. The Beijing Eye Study 2001/2011

Abstract

To assess the prevalence of myelinated retinal nerve fibers (MRNFs), the rate of their change in a 10-year follow-up, and associations with ocular and systematic parameters in a population-based cohort. Longitudinal population-based cohort study. The Beijing Eye study including 4,439 participants aged 40+ years in 2001 and was repeated in 2011, with 2,695 individuals (66.4% of the surviving) being re-examined in 2011. All participants underwent detailed physical and ocular examinations. MRNFs were diagnosed on fundus photographs and their change was assessed using a flicker method of fundus photographs. Out of 35 eyes (29 participants) with detected MRNFs at baseline (mean prevalence: 0.4% ± 0.26% per eye or 0.7% ± 0.41% per individual), 23 eyes from 20 individuals (17 [85%] participants with unilateral MRNFs) were re-examined in 2011. MRNF enlargement was detected in all 19 eyes (100%) with clear fundus photographs. The mean MRNF area increased from 4,233 ± 3,670 µm2 (range: 178-11,643 µm2) at baseline to 5,243 ± 4,092 µm2 (range: 196-13,297 µm2) at follow-up (P < .001), by 1,010 ± 1,026 µm2 (18-3,967 µm2) or by 47% ± 74% (9%-315%). A larger MRNF increase was associated with an MRNF location distant from the optic disc as compared to a juxtapapillary location (P=.001, standardized regression coefficient beta: -0.53), smaller MRNF area at baseline (P=.006, beta: -0.34), and higher serum concentration of low-density lipoproteins (LDL) (P < .001, beta: 0.57). MRNFs (mean prevalence per eye: 0.4%) showed, in association with higher LDL serum concentration and peripheral located MRNF, an enlargement during a 10-year follow-up, while in the same period no new MRNFs were detected in the total study cohort.