The Bhaktapur eye study: ocular trauma and antibiotic prophylaxis for the prevention of corneal ulceration in Nepal.

AIMS To determine the incidence of ocular trauma and corneal ulceration in the district of Bhaktapur in Kathmandu Valley, and to determine whether or not topical antibiotic prophylaxis can prevent the development of ulceration after corneal abrasion. METHODS A defined population of 34 902 individuals was closely followed prospectively for 2 years by 81 primary eye care workers who referred all cases of ocular trauma and/or infection to one of the three local secondary eye study centres in Bhaktapur for examination, treatment, and follow up by an ophthalmologist. All cases of ocular trauma were documented and treated at the centres. Individuals with corneal abrasion confirmed by clinical examination who presented within 48 hours of the injury without signs of corneal infection were enrolled in the study and treated with 1% chloramphenicol ophthalmic ointment to the injured eye three times a day for 3 days. RESULTS Over the 2 year period there were 1248 cases of ocular trauma reported in the population of 34 902 (1788/100 000 annual incidence) and 551 cases of corneal abrasion (789/100 000 annual incidence). The number of clinically documented corneal ulcers was 558 (799/100 000 annual incidence). Of the 442 eligible patients with corneal abrasion enrolled in the prophylaxis study, 424 (96%) healed without infection, and none of the 284 patients who were started on treatment within 18 hours after the injury developed ulcers. Four of the 109 patients (3.7%) who presented 18-24 hours after injury developed infections, and 14 (28.6%) of the 49 patients who presented 24-48 hours subsequently developed corneal ulceration. CONCLUSIONS Ocular trauma and corneal ulceration are serious public health problems that are occurring in epidemic proportions in Nepal. This study conclusively shows that post-traumatic corneal ulceration can be prevented by topical application of 1% chloramphenicol ophthalmic ointment in a timely fashion to the eyes of individuals who have suffered a corneal abrasion in a rural setting. Maximum benefit is obtained if prophylaxis is started within 18 hours after injury.