Knowledge acquisition and evaluation of an expert system for managing disorders of the outer eye

The aim of the current study was to develop and evaluate an expert system for diagnosing outer eye disorders, intended to support family physicians and nurse practitioners in the management of patients with minor eye complaints. The knowledge in the program was gathered from the scientific literature and from 6 experienced ophthalmologists and 6 ophthalmic nurses. Fourteen diagnoses must be considered, and the differential diagnosis is dependent upon 32 signs and symptoms. The program calculates the most likely diagnosis, presents photographs of the typical ocular findings, and provides information regarding management and treatment. The program's output was compared with the diagnosis made by 8 other ophthalmologists at a Swedish university clinic, based on data from 157 patients with disorders of the outer eye, who visited the emergency ward during a one-week period. The concordance between the diagnosis made by the ophthalmologists and the program was 96%. In conclusion, the expert system for disorders of the outer eye provided essentially the same diagnostic information as an examination by an ophthalmologist. Support from the program would make it possible for family physicians and nurse practitioners to manage most of these patients.