Résumé
A cross-sectional survey of eye disease supported by the African Programme for Onchocerciasis Conffol (APOC) was carried out in October 1998, in Raja, Sudan, a Savanna ecological zone to determine the prevalence and distribution of onchocercal eye disease. Detailed eye examination including measurement of visual field using the Wu-Jones computerized Motion Sensitivity Screening Test (MSST) were carried out. A total of 481 individuals were examined, of which 379 underwent detailed eye examination. A high prevalence of blindness (8.1%) from all causes was recorded. Onchocerciasis-induced eye disease was responsible for blindness in 56.40/o of all blind persons. Of the 38 persons who had visual impairment, 13 (2.7%) were severely affected. As many as 91 (24.0%) persons had microfilariae (mfs) in the anterior chamber (AC) and /or cornea with the highest prevalence of 29.3Yo and 28.8% respectively, recorded among the young and active individuals. This age group (15-24yeus) also had the highest prevalence (15.3%) of flufff corneal opacities. Sclerosing keratitis was present in 46 (12.1%) subjects while iridocyclitis was diagnosed in 9.0% with the highest prevalenc e of 25 .0o/o noted in the 45 - 54 age group. Prevalence of blinding cataract was 54.1% while that of glaucoma was12.2%. Presumed optic nerye disease, a known pathway to onchocercal blindness was observed in 19.6% with one third of this percentage already at the advanced stage. Another common pathway to blindness, chorioretinitis, affected 15.2% of the subjects of which 7.2% had reached advanced stages.Prevalence of abnormal visual fields was 6.6Yo. Posterior segment oncho disease was found to be the main ocular pathology in 15.6% subjects followed closely by 13.5% whose main cause was anterior segment oncho lesion. Both sexes were almost equally affected. Ocular findings in this area particularly among the young conform to high intensity levels of onchocerciasis infection and therefore require urgent effective intervention to forestall further devastating oncho-induced blindness and alleviate the socio-economic burden imposed on this population.