LOW VISION

This is a loss of eyesight that makes everyday tasks difficult.
A person with low vision finds it difficult or impossible to accomplish activities such as reading, watching television,
driving a car or recognizing faces.

When vision cannot be improved with regular eyeglasses, medicine or surgery, people with low vision need
rehabilitation to learn how to make the most of their remaining sight and keep their independence.

Vision Loss

Classification patterns of vision loss include:

CLASSIFICATION FEATURES
Central vision This is the detailed vision we use
when we look directly at something.
Age-related Macular degeneration
(AMD) affects central vision. Diabetic
retinopathy can affect central or
peripheral vision
Peripheral
vision
This is the less detailed vision we use
to see everything around the edges.
Glaucoma affects peripheral vision
first. Strokes can affect one side of the
peripheral vision
Contrast
sensitivity
This is the ability to distinguish between
objects of similar tones like milk in
a white cup or to distinguish facial
features. All eye problems can decrease
contrast sensitivity
Depth
perception
This is the ability to judge the position
of objects. New vision loss in one eye
can affect depth perception, such as the
height of a step
Visual
processing
The lens in our eye focuses light rays
onto our retina. The retina converts
these light rays into signals that are sent
through the optic nerve to our brain,
where they are interpreted as the images
we see. A problem with any of these
processes affects our vision in various
ways

Causes of vision loss

  • Congenital (e.g., prenatal or postnatal trauma, genetic or developmental abnormalities)
  • Hereditary (e.g., retinitis pigmentosa or Stargardt’s macular degeneration)
  • Acquired conditions (e.g., ocular infection or disease, trauma, age-related changes, or systemic disease)

Clinical features

  • Loss of the ability to read standard-sized print
  • Difficulty performing work-related tasks or leisure activities
  • Inability to recognise faces or familiar people

Investigations

  • History, visual Acuity
  • Refraction
  • Ocular motility
  • Binocular Vision Assessment
  • Visual Field Assessment
  • Ocular Health Assessment: external examination, Slit lamp exam, tonometry, fundoscopy with dilated pupil

MANAGEMENT

  • Low vision aids
  • Mobility instruction and community based rehabilitation
  • Co-management with optometrist, low vision worker, community rehabilitation worker
  • Counselling services (psychiatric, psychological and social work)
  • Occupational therapy