PAEDIATRIC LOW VISION (RE)HABILITATION
Comprehensive medical care includes preventive, curative and rehabilitation
medicine. In ophthalmology we usually talk about
- preventive ophthalmology or primary prevention,
- curative ophthalmology or secondary prevention of blindness and
- low vision rehabilitation or tertiary prevention of blindness.
All three aspects of prevention of blindness should be present in the work of
each unit. However, in a number of ophthalmological centres the work is
nearly solely curative forgetting the importance of primary prevention of
diseases and disorders and the need of rehabilitative services also in
The goal of low vision rehabilitation is to reduce the functional vision loss by
enhancing the visual function through the use of different optical and
non-optical devices and by compensating, substituting, the loss by the use of
new skills and techniques based on other modalities.
Although low vision rehabilitation is concerned with the tertiary prevention of
blindness, we need to have our eyes open for the possibilities of preventing
and taking care of diseases. It is particularly important in the therapy and
education of visually impaired children to notice any change in the childís or
young personís condition. An impairment does not preclude the possibility of
getting another disorder or disease that requires treatment, sometimes
So, if you see a school or preschool child deeply involved in knocking with his
fist on forehead as if listening to something, remember that the child may
be experimenting with flashing lights related to detachment of the retina and
do not take it as a sign of mental problems. Ideally, we should always know
about the possible new symptoms and signs that could occur in a disabled
child whom we take care of. Also, we can include in the daily program of the
children aspects of personal hygiene to prevent infections and teach them
about prevention of accidents in play, games and sports. In our work we are thus
involved with all the four important aspects: disorder, impairment, disability
The word disorder covers structural changes caused by diseases and trauma.
The structural changes may or may cause loss of vision so the diagnosis
alone does not depict the impairment.
The impairment means the measurable changes in the different subfunctions
of vision. The usual functions that are measured for the characterisation of
impairment are visual acuity and visual field but also visual functions like
contrast sensitivity, colour vision, visual adaptation to different luminance
levels, diplopia etc. characterise the impairment. Often visual impairment is
thought to be equal to impaired function of the eye. However, a lesion at any of the locations in the long visual pathway may cause visual impairment. Today, we do not have a good classification of visual impairment caused by changes in the function of posterior visual pathway and visual cortices or by disturbances in motor functions in vision.
The visual disability is assessed based on the use of vision in the four
important functional areas of daily life: communication, orientation and
mobility, activities of daily life (ADL) and sustained near vision tasks like
reading and writing.
Since more than half of our visually disabled paediatric population has other
disorders and disabilities, these need to be considered when ever we assess
the childís functioning. This is particularly important in the assessment of
dual sensory impairment.
The words impaired and disabled seem to have strong emotional contents to
a number of persons. Sometimes to the point that the word disabled or
disability are abandoned and impaired or impairment used instead. It should
be clearly understood that visual impairment as such is not interesting in
rehabilitation, it is interesting in reporting for primary prevention of blindness
and for need of therapeutic services whereas only when it causes disability it
becomes a interesting question in rehabilitation.
The visual handicap is situation or task bound. A disability causes a handicap
when it prevents the person from doing a task or makes it more difficult than it
would be to a fully sighted or it interferes with participation in the different
functions of the society.
In young children there is also an arrow backwards from visual impairment to
visual disorder because of the pliability of the visual system. In these cases
therapy functions also as treatment because it may bring considerable
improvement in the visual functioning, more than would be possible through
the age related development of vision without supportive therapy. This is an
extremely important aspect of paediatric early intervention. Because of this
possibility I would like to stress the importance of communication between all persons related to
early intervention and education of these children.
[ Back ]