Visually impaired Swedish children. The 1980 cohort study--a 19-year ophthalmological follow-up

To assess the ophthalmological outcome in a cohort of visually impaired children in a geographically defined area.

A 19-year follow-up of medical records, interview and, if needed, re-examination of the initial 128 patients, born 1962-1976.

Follow-up was possible in 123 patients (96%); 76 (59%) were still visually impaired, 17 (13%) were deceased, while 30 (23%) had acquired a visual function > or = 0.3. The chances of gaining a visual function outside the WHO limits for visual impairment was significantly higher for patients without additional impairments (p=0.0023). The initial ophthalmologic diagnosis remained unchanged in 88%. The diagnoses with improved visual development included albinism and congenital nystagmus, while retinal diseases showed poorer results. An increase in visual function could be seen even in the initially older age-groups, indicating a maturation of visual function beyond what is usually considered the limit of plasticity of the visual system.