Macular Thickness and Its Associated Factors in a Healthy Cynomolgus Colony: The Non-Human Primates Eye Study.

Purpose: The research aims to investigate the normal macular thickness range in a healthy cynomolgus colony and examine its association with relevant parameters. Design: Cross-sectional observational study. Subjects: A total of 418 healthy cynomolgus monkeys (mean age, 13.22 ± 7.86 years; range, 1-29 years) from the Non-Human Primates Eye Study conducted between 2021 and 2022. Methods: All included monkeys underwent comprehensive ocular measurements, including macular thickness measurement using spectral-domain OCT. To account for the correlation between eyes, generalized linear mixed models were applied. To assess the gender differences in macular thickness and volume, independent T-tests were employed. Linear regression, including quadratic terms (Age Main Outcome Measures: Macular thickness in ETDRS subfields and its associations with age and ocular parameters. Results: Sex statistically significant differences were observed only in the superior sector of the inner ring and in the temporal sector of the outer ring after adjustment. In inner rings, all 4 subfields exhibited a significant age-related decline; meanwhile, temporal and superior subfields decreased with increasing age in the outer ring. After adjustment, macular thickness was independently associated with age and end-of-anesthesia intraocular pressure (IOP) in the central region, axial length (AXL) in the average inner ring, AXL and mid-anesthesia IOP in the average outer ring, and AXL and end-of-anesthesia IOP for the overall average thickness. Conclusions: This study provided valuable reference data on macular thickness in different ages and sexes of cynomolgus which could be utilized in preclinical nonhuman primate experiments. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.