The epidemiology of low vision and blindness associated with trichiasis in southern Sudan

Ngondi, Jeremiah; Reacher, Mark; Matthews, Fiona; Ole-Sempele, Francis; Onsarigo, Alice; Matende, Ibrahim; Baba, Samson; Brayne, Carol; Emerson, Paul

Abstract

Background. We investigated vision status associated with trachomatous trichiasis (TT) and explored age-sex patterns of low vision and blindness associated with trichiasis in Mankien district of southern Sudan where trachoma prevention and trichiasis surgery were absent. Methods. A population based survey was undertaken and eligible persons underwent eye examination. Visual acuity (VA) was tested using Snellen E chart and persons with TT identified. Vision status was defined using the WHO categories of visual impairment based on presenting VA: normal vision (VA ≥ 6/18 in better eye); low vision (VA < 6/18 but ≥ 3/60 in better eye); and blindness (VA < 3/60 in better eye). An ordinal logistic regression model was fitted and age/sex specific distribution of vision status predicted. Results. Overall 341/3,567 persons examined had any TT. Analysis was based on 319 persons, 22 persons were excluded: 20 had both TT and cataract; and 2 had missing VA data. Of the 319 persons: 158(49.5%) had trichiasis-related corneal opacity (CO); bilateral TT and bilateral CO were found in 251(78.7%) and 110 (34.5%), respectively; 146 (45.8%) had low vision or blindness; the ratio of low vision to blindness was 3.2:1; and no sex differences were observed. In our model the predicted distribution of vision status was: normal vision, 53.9% (95% CI 50.9-56.9); low vision, 35.3% (95% CI 33.3-37.2); and blindness, 10.9% (95% CI 9.7-12.0). Conclusion. We have reported severe trichiasis and high prevalence of vision loss among persons with trichiasis. Our survey showed that almost 1 in 20 of the entire population suffered low vision or blindness associated with trachoma. The need for trichiasis surgery, trachoma prevention services, and rehabilitation of the blind is acute. © 2007 Ngondi et al; licensee BioMed Central Ltd.

Citation

Ngondi, J., Reacher, M., Matthews, F., Ole-Sempele, F., Onsarigo, A., Matende, I., …Emerson, P. (2007). The epidemiology of low vision and blindness associated with trichiasis in southern Sudan. BMC Ophthalmology, 7, https://doi.org/10.1186/1471-2415-7-12

• Journal Article Type: Article
• Publication Date: Nov 23, 2007
• Deposit Date: Dec 8, 2023
• Journal: BMC Ophthalmology
• Electronic ISSN: 1471-2415
• Publisher: BioMed Central
• Volume: 7
• DOI: https://doi.org/10.1186/1471-2415-7-12
• Public URL: https://hull-repository.worktribe.com/output/4455386