Causes of Visual Impairment and Blindness Among children in schools for the Blind in Yemen

Abstract

Background: Childhood blindness is increasingly becoming a major challenge worldwide. It is estimated that a child goes blind somewhere in the world every minute. Aim: To determine the causes of visual impairment and blindness in children in schools for the Blind in Yemen. Methods: Children attending 13 schools for the Blind in Yemen were examined during February and April 2009. A modified WHO/PBL eye examination record for children with blindness and low vision was used to categorize the anatomical and the etiological causes of visual loss. Data were analyzed by using the EPI-INFO 2004 programme. Results: A total of 453 students less than or equal to 16 years of age were examined in 13 schools for the Blind in 9 governorates of Yemen. Of the children examined, 120 (26.5%) were visually impaired (<3/9.5-≥ 3/60) and 288 (63.6%) were blind (<3/60-NLP). The major anatomical sites of visual loss were whole globe (30.0%) mainly buphthalmos, retina (26.6%), optic nerve (16.9%), lens (11.8%) and cornea (8.2%). The major etiology was hereditary in 50.0%, undetermined in 35.5% and postnatal/childhood factors in 13.5%. Nearly half of cases (49.2%) were considered to be potentially avoidable. The family history was positive in 229 (50.6%) and the products of consanguineous marriages was found in 199 (43.9%). In 39 children (8.6%), additional disabilities were present mainly mental retardation in 22 (4.9%). Conclusions: Hereditary diseases are the predominant causes of childhood visual loss in Yemen. Consanguineous marriages were highly observed in the parents of the children. The treatable conditions buphthalmos and cataract or poorly treated cataracts were the important leading causes of visual loss. Information about the causes of visual impairment and blindness is important for adequate provision of special services and for developing preventive strategies