Prevalence and causes of mono ocular blindness and visual impairment among vehicle drivers in Port Harcourt Nigeria

Abstract

Aim: To determine the prevalence and causes of mono ocular blindness and visual impairment among vehicle drivers in Port Harcourt, Nigeria.
Method: Four hundred commercial vehicle drivers in the 10 major motor parks of Port Harcourt LGA were interviewed and examined in this study. A structured questionnaire on demographic characteristics, driving and ocular history was administered. Ocular examination included visual acuity, refraction, visual field, tonometry, colour vision test and ophthalmoscopy. The
data collected was entered into computer using EPI-INFO statistical software for analysis. Ethical approval was obtained from relevant authorities.
Result: The prevalence of mono ocular blindness was 3.5% while that of visual impairment was1.8% in the better eye and 8.0% in the worse eye. The causes of monocular blindness were cataract (50%), glaucoma (35.7%), optic atrophy and corneal opacity contributed 7.1% each. Cataract found in 37 cases was also the leading cause of visual impairment (42.8%) while other common ocular problems were pterygium (26.7%), presbyopia (22.9%), glaucoma (11.5%), and refractive error (8.4%).
Conclusion: A good number of drivers in this study were still driving with mono ocular blindness and visual impairment. Cataract and glaucoma being the major causes of these visual problems can be tackled by enlightenment and provision of quality eye care services. Proper supervision of vision safety regulations and enforcement of rules by the relevant authorities is recommended to avoid fatal road traffic accidents.

Keywords: Mono ocular blindness, visual impairment, vehicle drivers.