The prevalence of glaucoma in an onchoendemic community in South-Eastern Nigeria.

METHODOLOGY: With the aim of examining all the adults aged 30 years and above a survey was conducted in Alum-Inyi, a mesoendemic Community in South-Eastern Nigeria. The people were subjected to basic ophthalmic tests for the diagnosis of glaucoma namely corrected and uncorrected visual acuity at 6 metres using an illiterate E-chart, with pinhole assessment if visual acuity < 6/18; direct ophthalmoscopy to assess the vertical cup-disc ratio through undilated pupils and Schiotz indentation tonometry. In addition, static visual field analysis using the MK 1 Friedman visual field analyser was carried out in any glaucoma suspect.

RESULTS

Of 664 eligible persons examined (out of the estimated total of 946), 14 definite cases of glaucoma were identified, giving a prevalence of 2.10% in the 30 years of age and older population. The mean vertical cup-disc ratio for the non-glaucoma cases were 0.30 (+0.004) and 0.31 (+/- 0.004) and 0.31 (+/- 0.09) in the right and left eyes respective. Among the glaucoma cases, the average vertical cup-disc ratio in the right and left eye were 0.63 (+/- 0.05) and 0.70 (+/- 0.06 respectively. No physiological cup of > or = 0.6 was recorded in our study. The mean iOP in the right and left eyes respectively were 18.54 (+/- 0.15) and 19.42 (+/- 0.14) in the nonglaucomatous cases and 26.39 (+/- 1.75) and 27.46 (+/- 2.59) in the glaucoma cases.

CONCLUSION

Despite its limitations, this study confirms that the prevalence of glaucoma varies from one African population or population of African origin to another. It agrees with other reports that the risk of glaucoma increases with age.