RELATIONSHIP BETWEEN OPTICAL COHERENCE TOMOGRAPHY FINDINGS AND OPTIC NERVE HEAD FINDINGS AMONG A NIGERIAN POPULATION: A RETROSPECTIVE STUDY.

BACKGROUND

Glaucoma is a leading cause of irreversible blindness worldwide. Early detection remains challenging, particularly in resource-limited settings where disc-based assessment is subjective. Optical Coherence Tomography (OCT) provides objective structural measurements such as retinal nerve fiber layer (RNFL) thickness and Bruch's membrane opening (BMO)-minimum rim width (MRW), which may improve diagnostic accuracy.

AIM: To evaluate the relationship between OCT-derived parameters and optic nerve head findings among individuals classified as glaucoma suspects or cases using International Society of Geographical and Epidemiological Ophthalmology (ISGEO) criteria in a Nigerian population.

METHODS

This retrospective study included 310 participants screened during the 2024 World Glaucoma Week at a tertiary hospital. Glaucoma and suspects were defined using ISGEO criteria. OCT imaging (Spectralis SD-OCT) was performed in 55 participants (39.9% of suspects/cases). Global and sectoral RNFL thickness and MRW were analyzed using linear mixed-effects models adjusting for age, sex, and family history.

RESULTS

Of the 310 participants, 138 (44.5%) were classified as glaucoma suspects or cases, including 24 (7.7%) with glaucoma. RNFL thickness did not differ significantly between groups (all p≥0.46). In contrast, MRW was significantly thinner in glaucoma cases globally (b = µ26.5 mm; p = 0.043) and in multiple sectors (p < 0.05). Family history was independently associated with glaucoma status (adjusted OR = 1.98; p = 0.031).

CONCLUSION

MRW demonstrated superior discriminatory ability compared to RNFL thickness in differentiating ISGEO-defined glaucoma cases from suspects. These findings support the complementary role of MRW in glaucoma assessment where OCT is available.