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Contribution of refractive errors to visual impairment in patients at korle-bu teaching hospital
1Ophthalmology Unit, Department of Surgery, University of Ghana Medical, P.O. Box GP 4236, Accra, Ghana.
Summary Objective:
To determine the contribution of refractive error to visual impairment in visually impaired patients attending Korle-Bu Teaching Hospital, Ghana.
Method:
This study was conducted over a period of 1 year beginning October 2002 at Korle-Bu Teaching Hospital. Every 4th consecutive new case attending the eye clinic, aged 6 years and above was selected and interviewed using a structured questionnaire. A Snellen's chart was used to determine the unaided visual acuity, visual acuity with spectacles where the patient was wearing one, and visual acuity with pin hole with or without spectacles. Improvement in visual acuity by 2 or more lines on the Snellen's chart when looking through the pin hole was regarded as an indication of refractive error.
Results:
A total of 1,069 respondents, 594 female and 475 male were recruited into the study. One hundred and fifteen (115) patients (10.76%) were found to have impaired vision (Visual acuity worse than 6/18 to PL in the better eye). The vision of 51 of those with impaired vision improved when looking through the pin hole. Refractive error with Visual Acuity worse than 6/18 was present in 4.8% of all patients who attended the eye clinic. Refractive error was present in 44.3% of patients with visual impairment.
Conclusion:
Visual impairment was a common presentation and uncorrected refractive error was a major cause of visual impairment.
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