Retinitis Pigmentosa – (RP)

Description

  • retinitis pigmentosa (RP) is a hereditary eye disease which causes
    degeneration of the retina. The retina slowly degenerates and loses its
    ability to transmit images to the brain. Characteristic clumps of pigment
    appear on the retina in later stages of RP (this is seen through an ophthalmoscope)
  • there are different genetic forms of RP
  • the student with RP often loses peripheral vision first, often described
    as tunnel vision. In some cases there is a central vision
    disturbance at the same time as the peripheral vision is degenerating.
    In many cases central vision retains relatively high acuity, whilst there
    is an absence of receptors in the periphery (ie cone cells)
  • one symptom of RP is night blindness. Night blindness
    occurs because central vision does not function with low illumination
  • RP can eventually lead to total blindness, though most people retain
    limited vision for years after diagnosis. Statistics suggest that the
    earlier the onset of the RP, the more the vision will degenerate. Degeneration
    rates differ from individual to individual. For some, vision loss is slow,
    whilst for others vision loss may occur rapidly, or in bursts and plateaus
  • a person with less than 10° of visual field remaining is classified
    as legally blind, and is eligible for the blind pension
    at 16 years of age. The handicapped child allowance is available to a
    legally blind child under the age of I6 years.

Some syndromes which include RP

  • Usher’s Syndrome – this syndrome includes hearing impairment.
    There are two types of Usher’s Syndrome – type one and type two.
    The students with type one are more likely to develop symptoms of RP earlier
    than those diagnosed with type two
  • Laurence-Moon-Bardet-Beidl Syndrome – the symptoms of this syndrome
    can include RP, polydactyly (extra digits), obesity, intellectual impairment,
    congenital heart disease, scantness of body hair, shortness of stature
    and genital hypoplasia (underdeveloped genitals).

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
  • illumination is critical for student with RP. A student with RP will
    require high illumination to avoid night blindness. Some
    students may require additional illumination (eg a lamp), to be used at
    their desk. High quality torches can be useful for dark areas eg keep
    a torch in a locker to assist with locating books, a penlight in a pencil
    case can be useful, a penlight attached to a key ring is useful for negotiating
    a locker key and a torch beside the student’s bed when on school
    camp – for those middle of the night toilet trips
  • orientation and mobility difficulties may occur due to peripheral vision
    loss. A student with RP will need to be taught to turn his/her head to
    see beyond his/her field of view. Students with a RP may need additional
    orientation and mobility training
  • students with limited central visual field may benefit from a reduction
    in the size of print they use
  • consider contrast when producing/presenting materials to a student
    with RP
  • 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
  • reading strategies may need to be developed to compensate for a narrowed
    field of view. With a reduced field, the student will see only a few words
    or letters at a time. Visual memory and the ability to chunk
    information can be a helpful strategy
  • utilise high contrast materials eg black texta for writing, textas
    for drawing, coloured paste, using clear bold illustrations to cut around
  • bold lined paper may assist
  • consider acceptance of impairment. A student with a degenerative impairment
    may be going through a grieving process. Loss of peripheral vision can
    cause mobility difficulties which can produce anxiety and a loss of confidence
    in moving about in the environment
  • keep the classroom layout as static as possible
  • 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
  • assist student in locating where s/he is required to look eg The
    handwriting task is on the left hand side of the chalkboard
  • the speaker should be in front of the student with RP (or best field
    of vision), particularly with students with an additional hearing impairment
  • 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 etc
  • 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 relaxation
  • 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
  • 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
  • reading environmental signs eg street signs may cause difficulties.

Some useful resources

  • Retina Australia represents people who have Retinitis Pigmentosa and
    other Retinal Dystrophies.
    Phone: 03 9650 5088.
  • Usher’s Syndrome – Vision and Hearing Loss (information kit), produced
    by The Usher Committee c/o Deaf Blind Care Association, PO Box 267, Clifton
    Hill 3068.
    Phone: (03) 9482 1155.

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.