Retinal Thinning Rates Vary Between Glaucomatous Optic Disc Phenotypes

Senile sclerotic optic discs had the fastest rate, according to the study.

In early glaucoma, circumpapillary retinal nerve fiber layer (cpRNFL) thinning patterns were different among 4 glaucomatous optic disc phenotypes. Senile sclerotic optic discs had the fastest rate of global cpRNFL thinning, according to research published in the American Journal of Ophthalmology. As such, these patients may benefit from more frequent monitoring or more advanced therapy if cpRNFL thinning is detected.

Managing glaucoma requires detecting the disease early via structural and functional changes. Optical coherence tomography (OCT) quantifies structural parameters of the optic disc and cpRNFL with precision and reproducibility, according to researchers. 

In this clinical cohort study, 218 early glaucoma eyes with at least 3 years of follow-up and a minimum of 4 spectral-domain OCT scans were examined. Optic discs were classified into 4 types based on appearance: 76 generalized cup enlargement (GE), 53 focal ischemic (FI), 22 myopic glaucomatous (MY), and 67 senile sclerotic (SS). 

Investigators found that after adjusting for confounders, the SS group (mean [95% CI]: -1.01 [-1.30, -0.73] µm/yearear) had the fastest mean rate of global cpRNFL thinning followed by FI (-0.77 [-0.97, -0.57] µm/year), MY (0.59 [-0.81, -0.36] µm/year), and GE (-0.58 [-0.75, -0.40] µm/year) at P <.001. The inferior temporal sector had the fastest rate of cpRNFL thinning among the regional measurements except for the MY group (-0.68 [-1.10, -0.26] µm/year, P =.002). In the multivariable analysis, GE (P = .002) and MY (P = .010) phenotypes were associated with significantly slower global cpRNFL thinning rates than the SS phenotype.

This study’s limitations include optic disc phenotype classifications being based on subjective observation. Uncontrolled differences in ocular and systemic characteristics between optic disc phenotype groups could affect the cpRNFL measurements, only pure optic disc phenotypes were included, and that IOP-lowering therapy may decrease the true effect of distinct phenotypes on the rates of cpRNFL thinning.

Disclosure: Some of the study’s authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.


David RCC, Moghimi S, Ekici E, et al. Rates of retinal nerve fiber layer thinning in distinct glaucomatous optic disc phenotypes in early glaucoma. Am J Ophthalmol. 2021;229(4):8-17. doi:10.1016/j.ajo.2021.04.010.