[Optic disc features on OCT in glaucomatous and normal black Africans]

Area of Science:

• Ophthalmology
• Glaucoma Research
• Optic Nerve Head Imaging

Background:

• Glaucoma is a leading cause of irreversible blindness worldwide.
• Optic nerve head (ONH) morphology is a key factor in glaucoma diagnosis and progression.
• Understanding ONH size correlations with glaucomatous defects is vital for early detection.

Purpose of the Study:

• To investigate the relationship between optic nerve head (ONH) size and glaucomatous defects in a black African population.
• To determine correlations between ONH parameters and retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) measurements.

Main Methods:

• Retrospective observational study of 586 eyes from 298 black Togolese patients.
• Optic nerve head (ONH) size categorized into small, medium, and large based on surface area.
• Correlation analysis using Pearson's coefficient (r²) to assess relationships between ONH size, cup size, neuroretinal rim area, and RNFL thickness.

Main Results:

• ONH size showed a strong correlation with optic cup surface area (r²=0.7).
• RNFL thickness was weakly correlated with ONH surface area (r²=0.39) and moderately with neuroretinal rim area (r²=0.57).
• Significant differences in neuroretinal rim, cup, cup-disc ratio, and RNFL thickness were observed across ONH size groups.

Conclusions:

• Optic nerve head (ONH) size is correlated with optic cup size but not directly with neuroretinal rim area or nerve fiber thickness.
• Analysis of RNFL and GCC is essential for glaucoma diagnosis, especially in individuals with large ONHs.