A Clinic-based Survey of Blindness in Kenya.

During the course of a seven-month period in 1998 and 1999, 617 new patients with unilateral or bilateral blindness were evaluated as to the underlying cause. This was done at the Lighthouse for Christ Eye Centre in Mombasa, Kenya. These patients came not only from the Mombasa area, but from the entire coastal region — from the frontier with Somalia in the north to the border with Tanzania in the south. Others were from towns in the interior along the highway to Nairobi. Many of these had been made aware of the medical and surgical care available at the Lighthouse through our mobile clinics. Upon arrival at the Lighthouse each patient was registered and then a history of vision problems was obtained. Visual acuity was measured using the Snellen E chart at six metres. Patients were then examined with a slit-lamp, an applanation tonometer and either a direct or indirect ophthalmoscope. Where question existed regarding the degree of vision loss, the patient was referred to the clinic refractionist. With the exception of twelve patients seen by the clinical officer, all others were evaluated by one of the ophthalmologists at the Lighthouse. Patients with visual acuity of less than 3/60 in one eye, but 3/60 or better in the other eye were considered unilaterally blind. Those with less than 3/60 in both eyes were considered bilaterally blind. When compound causes for blindness were present in one eye, the most preventable or avoidable one was selected as the main cause of the blindness. This same principle was applied when different causes led to blindness in both eyes.