- opacification of the normally clear lens due to a variety of causes
- often associated with aging
- most cataracts are bilateral, but usually progress at different rates in
- cataracts may be:
congenital – present at birth or developed shortly after birth existing without
other impairments; or associated with conditions such as Rubella syndrome,
Down syndrome etc.
acquired – caused by the aging process, trauma or associated with the development
of another eye disease (eg glaucoma, diabetes etc).
- with cataracts, vision is usually blurred or indistinct, but this depends
on the size, position and density of the opacity
- cataracts cause reduced visual acuities – generally the decrease in visual
acuity is directly proportional to the size, position and/or density of the
- cataracts cause light to be scattered over the retina meaning that bright
light and glare will usually cause problems for the student
- night vision is not usually affected
- as the cataract progresses, near vision is affected first
- colour vision may be affected, especially the perception of blue.
- where cataracts are small or centrally located, acuities may be improved
significantly by the regular use of dilating agents (drops or ointment). Dilation
of the pupil allows the student to see around the cataract
- where vision is markedly affected, surgery may be recommended. The procedure
usually involves removing the entire lens – the eye is then known as aphakic.
Aphakia or loss of the lens means that the eye has lost the ability to accommodate
(ability to focus the image clearly on the retina)
- an artificial lens may be implanted
- the aphakic student must wear thick spectacles or contact lenses to compensate
for the loss of the lens. For reading tasks, reading glasses or bifocals will
- for congenital cataracts, surgery is usually undertaken soon after birth.
If not, the macula will remain poorly developed.
Suggested teaching strategies
- ensure that all staff working with the student, including replacement teachers
and volunteers, are aware of the vision impairment and its educational implications.
In the Classroom:
- seating position within the classroom is critical. Glare must be minimized
– the student usually needs to be seated close to the front of the class with
the source of glare behind. If too much light enters the room, blinds or artwork
can be placed over windows
- the use of shiny surfaces (eg white boards, shiny paper for flashcards
or worksheets, shiny table tops) should be avoided as they can reflect light
toward the student’s eyes
- reading material often needs to be modified eg tactual diagrams, audio
format, braille, enlargement. For young students it may be sufficient to bring
reading material close to the eyes
- utilise high contrast materials eg black texta for writing, textas for
drawing, coloured paste, using clear bold illustrations to cut around
- for writing sheets or exercise books, recycled paper (creamy or grey coloured)
may be better than pure white paper, but remember that contrast is also important
- always use a clean chalk board with white or yellow chalk or white board
with black marker. Use a consistent layout when presenting information on
a board eg homework is always found on the far right hand side of the board
- a reading/writing stand can often assist, especially in primary school
or for prolonged visual tasks. The use of a reading/writing stand will also
help to occlude light from the eyes
- for older students, a magnifier or CCTV may need to be prescribed for near
work. If using a CCTV, students with cataracts may prefer to read white print
on a black background
- paper colour, print size and type of magnification (hand held or stand
magnifier, photo-enlargement or CCTV) will need to be assessed on an individual
- bold lined paper may assist
- students will benefit from desktop demonstrations ensuring visual access
eg correct handwriting formation of a new letter, science experiment etc
- organisational skills may require development. Developing efficient organisational
skills will assist a student with a vision impairment eg having a large pencil
case to store pens, calculator and visual aids; setting aside extra time to
collect any equipment required; allowing extra time to complete visual tasks
- additional verbal description and verification may be required to ensure
the student has access to his/her environment eg describe a new classroom
or excursion venue, provide verbal praise etc. The student with a vision impairment
may miss a smile of encouragement
- the use of a personal computer (eg laptop) may be of great assistance to
a student with a vision impairment as an alternative to handwriting and to
reduce visual fatigue. Software is available for enlarging text and graphics,
including icons, menus etc. Voice output is available for both IBM and Macintosh
computers. Individual assessment of the needs of each student is essential.
Keyboarding skills should be taught in primary school
- strategies to reduce vision fatigue should be considered eg appropriate
visual rests may include listening to audio tapes both for information and
- students with a vision impairment often need to be taught social skills
using a direct teaching approach. Modeling appropriate social behaviors can
be difficult when you cannot see them accurately
- students with a vision impairment may need additional orientation and mobility
- thick glasses can attract unpleasant attention from other students – understanding
and acceptance of the student’s vision impairment, individual learning
modes and work production methods (eg braille, computer etc) may be facilitated
through carefully planned simulation activities and class education programs.
- glare will cause problems – the teacher should keep the sun behind the
student when addressing him/her
- students may be more comfortable wearing darker colours, especially on
their upper body. Light coloured clothing may cause glare and discomfort especially
- sun hats can be useful to shield the eyes from glare
- reading environmental signs eg street signs may cause difficulties.
These notes were made by the staff of the Statewide Vision Resource Centre.
They are general statements and may not apply to all students with this condition.