Children in blind schools: what conditions should be treated?
During our team’s routine screening of children in blind schools in Madurai, we find a considerable number of children every year who can benefit by being given spectacles, simple magnifiers or by surgery. This situation can be attributed to the fact that many of these children were not seen by an ophthalmologist before admission to these schools.
Children who have vision better than counting fingers (CF) should be investigated thoroughly and this includes anterior segment examination, refraction and fundoscopy. With the preliminary diagnosis in hand, the examination of refraction should be given more importance. It may be practically difficult but every effort should be made to achieve the best corrected visual acuity with appropriate glasses. Many times we come across children with high myopia, macular dystrophy, congenital nystagmus, microphthalmos, albinism, coloboma, cone dystrophies, and sometimes even optic atrophies showing significant improvement for both distance and near vision or sometimes with near vision alone. Apart from doing routine refraction, steps should be taken to ascertain the acceptance of simple low visual aids.
Often these children show very good improvement with telescopes. The improved visual acuity (telescopic) could even be 6/6. Near vision also can be improved in the same way with simple magnifiers. It needs a lot of motivation from parents, teachers and the children to use these devices later in childhood. Reluctance is always experienced particularly since most of these children are trained in the use of Braille.
The children who show minimal improvement or no improvement at all, even with low visual aids, are often those with uncorrected aphakia because of dense stimulus deprivation amblyopia.
The most important and significant pathology causing blindness which was untreated has been congenital cataract. In this category of children are those who have had no treatment or had treatment but were not followed up properly or ended up with complications. Under the ‘Seeing 2000’ programme sponsored by the International Eye Foundation, 245 children admitted into blind schools in the city were examined by us in 1998. The main objective was to identify children who could benefit by surgery. Of the 245 children, 16 were found to be blind due to unoperated cataracts in both eyes. Thirteen were uncorrected aphakics. Among the unoperated children with cataract, nine had surgery. The remaining seven did not have surgery mainly because of less motivation by their parents. The minimum vision gained by those who had surgery was CF and the maximum vision was 6/60 (Table 1). Among these, three had intraocular lens (IOL) implants. Most children had only cataract extraction, either extracapsular cataract extraction (ECCE) or lensectomy, depending on the nature of the cataract (partially absorbed or calcified). Nystagmus was present in almost all cases. The number of children showing improvement post-operatively even at this late stage of childhood is encouraging and justifies the undertaking of surgery after proper investigation. The visual improvement was less when the child had associated micro-cornea, microphthalmos or coloboma.
Table 1. Children with cataract showing visual improvement after surgical intervention
|Number||Age||Surgical Procedure||Pre-op. VA||Post-op. VA|
|3||8||ECCE + IOL||HM||CF|
|7||12||ECCE + IOL||PL||1/60|
Table 2. Aphakic children showing improvement with correction
|No.||VA (without correction)||VA (aphakic with correction)||NV||DV (telescope)||NV (hand magnifier)|
Among the 13 children who had already had surgery but were uncorrected, only a few showed visual improvement with aphakic correction (Table 2). Only patient No.12 showed significant improvement with a telescope. Others were either not co-operative or unable to ‘fix’ because of nystagmus. Most were densely amblyopic and the visual acuity ranged from CF to 6/60. This strongly supports the fact that bilateral childhood cataract in South India is a significant cause of childhood blindness and accounts for 12% of admissions to blind schools.
One more condition which could be treated surgically is corneal opacity of late onset due to acquired pathology such as keratomalacia. Either keratoplasty or optical iridectomy before dense amblyopia develops is worth trying.
To conclude, we would like to emphasize that all the children who are likely to be admitted into blind schools should be thoroughly examined by an ophthalmologist. The eye specialist should have a background of working with children and a knowledge of amblyopia and the use of low visual aids. With this approach, and if simple low visual aids are introduced early in life, the quality of education and life can be significantly improved.
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