Aim: To investigate the causes of low vision and blindness among the pupils in a school for the blind.
Methods: Full ophthalmic assessment was carried out including visual acuity assessment, anterior and posterior segments examination, and where possible, intraocular pressure. Hence both the anatomical and aetiological causes of low vision/ blindness were determined.
Results: One hundred and eleven pupils were present during the period of the study while 110 consented and participated in the study. The ages ranged from 6-32 years with a mean of 14.5 +/- 5.6 years. Sixty-nine students (62.7%) were aged less than 16 years while 41 (37.3%) were aged 16 years and above. About forty-six percent (46.4%) had PVA of nil light perception (NLP) while 38.2% had PVA of <3/60- LP (category 4). Hence, the prevalence of low vision (PVA <6/18- 3/60) in this population was 14.6% while that of blindness (PVA< 3/60) was 84.6%. The commonest anatomic site responsible for visual loss was whole globe (38.2%). This was followed by retina (25.5%), lens (17.3%), cornea (7.3%) and uvea (1.8%). Only 29 (26.4%) had previously undergone any form of eye surgery. The commonest aetiological group in terms of timing of insult causing visual loss was made up of conditions whose aetiology ‘cannot be determined’ (36.4%). The second commonest group was childhood factors (34.5%). This was followed by hereditary factors (25.5%).
Conclusion: Avoidable childhood factors are the principal causes of blindness in this population. Therefore, there exists an urgent need to tackle these factors to save our future generations from needless blindness.