Introduction
According to the definition of WHO, blind children aged 0 to 15 years are those with the best corrected visual acuity of the better eye being less than or equal to 0.1 (6/60). For severe visual disability in children, the corrected visual acuity of the better eye is less than or equal to 0.3 (6/18). For visually impaired children the term visual aid is used, and for adults - visual rehabilitation.
Aim:
The aim of this article is to study the functional vision of children from the school for the blind `Prof. Dr. Ivan Shishmanov` - Varna, assessing the effect of long-term specialized training and visual rehabilitation.
Materials and Methods
The children from the specialized school for blind `Prof. Dr. Ivan Shishmanov` - Varna were studied in 2009 and 2018. During the initial study 23 children were examined and in 2018 the children were 16. The visual acuity and the objective state of the eye were examined at the first visit. During the second one, in addition to visual acuity, we checked functional vision through a specially developed and adapted questionnaire. Low vision rehabilitation in the school is provided by auxiliary magnification devices.
Results
At the first visit in 2009, a total of 23 children from grades 1-3 were examined. During the second visit in 2018, 16 students were examined. There were five children with one-eye blindness and 18 with low vision in both eyes. Ten children were recommended for visual aids through a magnifier, six were targeted for correction with dioptric glasses, for four only Braille was possible, and three did not get any specific recommendation, as they did well without aids, according to the visual therapist. Nine years later, it was found that eleven children used a magnifier, seven of them using a magnifying glass and an electronic magnifier, and only one child used dioptric glasses and a magnifier. The remaining three children used a magnifying glass. The most preferred magnification was 5x, used by six children (37.5%). Three students learned only be means of Braille. The assessment of functional vision showed positive development of near vision skills. The students held the optical devices correctly in 93.75% of the cases and recognized a face in 81.25%. The evaluation of the activities at distance showed 100% success in climbing stairs. Additional training with a magnifying device is still need in 50 %. In 12.5% of the cases the aid device was completely rejected.
Conclusion
Our study found that most of the children with visual impairment in the school had enough useful sight capacity. The learning of Braille was often combined with the flatbed font, in addition to enlarged or bigger-sized fonts on optical or electronic devices. All students in the specialized school knew Braille, but a large part of them also use the flatbed fonts. Their high motivation to cope with magnifying devices coincided with their good adaptation and developed skills. This confirms the effective need for visual rehabilitation also for children as early as possible.
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