It is not uncommon to find children who have low vision attending mainstream schools. These children have the mental capacity to cope with the educational demands; however, they still have to encounter visual challenges gallantly. The World Health Organisation (WHO) defines a person with low vision as one who has impairment of visual functioning even after treatment and/or standard refractive correction, and has a visual acuity of less than 6/18 to light perception, or a visual field less than 10 degrees from the point of fixation, but who uses, or is potentially able to use, vision for the planning and/or execution of a task for which vision is essential. It is well known that the optometrist will find the most appropriate optical device to assist these learners but is there any other support that these clinicians can provide these learners?
How is visual impairment classified?
The International Classification of Diseases (2018) classifies vision impairment into two groups, distance and near presenting vision impairment.
Distance vision impairment:
- Mild – presenting visual acuity worse than 6/12
- Moderate – presenting visual acuity worse than 6/18
- Severe – presenting visual acuity worse than 6/60
- Blindness – presenting visual acuity worse than 3/60
Near vision impairment:
- Presenting near visual acuity worse than N6 (6/12 distance equivalent) or N8 (6/15 distance equivalent) at 40cm with existing correction.
Key global statistics according to the World Health Organisation
- Globally, it is estimated that approximately 1.3 billion people live with some form of vision impairment.
- With regards to distance vision, 188.5 million people have a mild vision impairment, 217 million have moderate to severe vision impairment, and 36 million people are blind.
- With regards to near vision, 826 million people live with a near vision impairment.
- Globally, the leading causes of vision impairment are uncorrected refractive errors and cataracts.
- Approximately 80% of all vision impairment globally is considered avoidable.
- The majority of people with vision impairment are over the age of 50 years.
So, how can an optometrist assist visually impaired learners who attend mainstream schools?
Firstly, visually-impaired learners attending mainstream schools in South Africa can be assisted by optometrists providing the best-corrective device. Secondly, the principal of the school has to be notified of the visual status of the learner. In light of this, the Department of Basic Education allows the learner 10 minutes extra per hour of test/examination. This means that for a 3-hour paper, the learner gets an extra thirty minutes. Also, the examination papers are printed in larger font size. This effort by the optometrist supports and promotes the learner’s development and educational experience.
Low vision is a form of visual impairment and is a significant reduction in vision caused by eye diseases, trauma or congenital conditions. The impact of visual impairment has important health, socio-economic, and quality of life implications. Optometrists are encouraged to interact with schools to assist visually-impaired learners in maximising their learning opportunities.
- WHO Fact sheet on Blindness and Visual impairment 11 October 2018.
- Methods of assessment of avoidable blindness. WHO Offset Publication Geneva. 1980 No. 54.
- Bourne RRA, Flaxman SR, Braithwaite T, Cicinelli MV, Das A, Jonas JB, et al.; Vision Loss Expert Group. Magnitude, temporal trends, and projections of the global prevalence of blindness and distance and near vision impairment: a systematic review and meta-analysis. Lancet Glob Health. 2017 Sep; 5(9):e888–97.
- Fricke, TR, Tahhan N, Resnikoff S, Papas E, Burnett A, Suit MH, Naduvilath T, Naidoo K, Global Prevalence of Presbyopia and Vision Impairment from Uncorrected Presbyopia: Systematic Review, Meta-analysis, and Modelling, Ophthalmology. 2018 May 9