[An investigation on causes of blindness of children in seven blind schools in East China].

OBJECTIVE: To determine the anatomical sites and underlying causes of blindness and severe visual impairment (BL/SVI), potentially preventable and treatable causes in East China.
METHODS: Between April 1998 and May 1999, a total of 385 children attending seven blind school in East China area were examined, and WHO Prevention of Blindness Program (WHO/PBL) Eye Examination Record for children with blindness and low vision was used.
RESULTS: Of the 385 children, 356 (92.5%) were blind or visually impaired severely (visual acuity less than 0.1 in the better eye). The commonest anatomical sites of BL/SVI were lens (27.5%), retina (22.5%), whole globe (15.2%) and optic nerve (14.9%). The commonest eye diseases were cataract (26.4%), retinal dystrophy (10.7%), optic nerve hypoplasia (8.4%). The aetiologic causes were hereditary factors (35.1%), meningitis (5.3%), trauma (2.8%), vitamin A deficiency (0.6%) and so on, drugs or alcohol taken during pregnancy (6.2%), retinopathy of premature infant (2.8%). Corneal scarring due to vitamin A deficiency or infection was not a major cause of visual loss. It was considered that 47.5% of cases were avoidable blindness, i.e. 23.0% potentially preventable and 24.4% potentially treatable.
CONCLUSIONS: Along with the improvement of health and socio-economic status, nutritional and infective causes of blindness are uncommon, and now hereditary factors become the major causes in children. We shall propagandize rudimentary knowledge of ophthalmology actively, and strengthen the building of pediatric ophthalmology, so as to prevent and treat childhood blindness better.