A comparison of optic disc size and retinal thickness between a glaucomatous and nonglaucomatous African population

This study identified retinal biomarkers for various stages of primary open-angle glaucoma (POAG) severity in a high-risk Ghanaian population. The findings of this study may guide eye-health professionals in determining the POAG risk for Ghanaians to allow for early detection and management as a strategy to reduce POAG-related visual impairment.

This study aimed to determine the most reliable POAG retinal biomarkers for different stages of disease severity in a Ghanaian population.

Optic coherence tomography (OCT) was conducted on 487 persons with POAG and 339 controls using Zeiss Cirrus HD-OCT. Peripapillary retinal nerve fiber layer (ppRNFL), macula ganglion cell complex, and optic nerve head measurements were extracted from the OCT test results. POAG participants were classified into three groups based on disease severity. Cohen's d effect size and adjusted odds ratios (aOR) were used to determine the POAG predicting ability of the retinal parameters.

Superior and inferior ppRNFL were POAG biomarkers across all stages of POAG severity; early POAG (superior ppRNFL: Cohen's d effect size = 1.50, aOR = 0.03 and inferior ppRNFL: Cohen's d effect size = 1.55, aOR = 0.04), moderate POAG (superior ppRNFL: Cohen's d effect size = 2.03, aOR = 0.02 and inferior ppRNFL: Cohen's d effect size = 1.93, aOR = 0.02), and advanced POAG (superior ppRNFL: Cohen's d effect size = 2.79, aOR = 0.01 and inferior ppRNFL: Cohen's d effect size = 2.79, aOR = 0.02). The inferior sector of the macula ganglion cell complex was a significant POAG biomarker at the early (Cohen's d effect size = 0.94, aOR = 0.08) and moderate (Cohen's d effect size = 1.48, aOR = 0.05) stages of the disease, while inferotemporal sector was the best biomarker for the advanced stage (Cohen's d effect size = 2.20, aOR = 0.01). Larger optic disc area measurements were highly associated with early POAG (Cohen's d effect size = 0.89, aOR = 3.52) and fairly associated with moderate (Cohen's d effect size = 0.66, aOR = 1.63) and advanced (Cohen's d effect size = 0.46, aOR = 1.45) POAG.

The identified parameters may aid eye-health professionals in determining POAG risk for Ghanaians to allow for early detection and management.