Low vision

Home / Vision defects / Low vision

Low vision

Low vision

What is low vision?

Low vision, or visual impairment, is due to a significant decrease in visual acuity or a reduction in the field of vision. The term low vision is used when this degradation limits the fulfillment of daily tasks.
Anyone can suffer from low vision at any age, but elderly people are the most commonly affected.

Low vision can have several causes: Age-related macular degeneration (AMD), cataracts, glaucoma, diabetes, retinitis pigmentosa, etc.

What are the symptoms of low vision?

Low vision results in:

  • A reduction in the central vision: this causes difficulties reading, writing, carrying out tasks requiring precision, interpreting colors and recognizing faces. Macular degeneration and diabetic retinopathy are the most common causes.
  • A reduction in the peripheral vision: the field of vision is reduced as if looking through a tunnel. This results in difficulty moving around without bumping into objects. Advanced glaucoma and retinitis pigmentosa are examples of this.

Some pathologies

  • AMD is a condition affecting the macula, the central part of the retina which enables the precise vision so vital for reading, writing and the recognition of details. It leaves only the peripheral or lateral vision intact.
    Although this disease occurs with age, its exact causes are only partially understood. Risk factors in AMD include heredity and smoking.
  • Retinitis pigmentosa leads to a progressive loss in peripheral vision. This is the most frequent cause of blindness in middle aged patients in developed countries.
  • A cataract occurs when the crystalline lens opacifies, which prevents light from passing through. Vision gets blurred, the perception of colors is dulled, and the eye becomes very sensitive to light.
    Cataract is one of the leading causes of visual impairment in the world, which generally appear in persons aged over 60 due to ageing of the eye, but may also affect young children (congenital cataracts).
  • Glaucoma alters the field of vision, particularly peripheral and lateral vision. Glaucoma is often associated with an increase of pressure within the eye.
  • Diabetic retinopathy is the most common cause of blindness in adults. It is a degenerative disease which affects sufferers of diabetes. It occurs when excess sugar in the blood damages the vessels supplying the retina with nutrients and oxygen.