Cone-Rod Dystrophy

Congenital genetic-hereditary phenomenon. Disease incidence 1: 40,000 births.
The retina is the part of the eye that absorbs light. It consists of two types of receptors, which are the cells that receive light and convert the image into electrical signals that pass to the brain.

There are 2 types of receptors: 1. Rods 2. Cones.

  1. The cones are responsible for visual detail, colors, central vision and day vision.
  2. The reeds are responsible for peripheral vision and night vision.

The disease affects the 2 systems together, when first there will be damage to the cones (Cones and therefore visual acuity is less good, there will be damage to color vision and hypersensitivity to light. Then there will also be damage to the reeds (Rods) and will develop night vision difficulty and many difficulties in mobility due to loss of peripheral vision.

Functional implications:
The disease has no preventative or curative treatment although less exposure to light may slow the rate of disease progression. Blunt glasses that help due to the sensitivity to light are essential and it is also important to emphasize mobility education from a young age (when there is still peripheral vision). Due to the damage to central vision it is necessary to work with magnifications and aids, allow the child to approach objects (this causes magnification and then it is easier to identify them) and not to rely on colors. When age and mental level allow, children with optical devices should be helped to have visual impairment.

* A similar / parallel disease is Rod-Cone Dystrophy where the difference is that here the damage begins in the system of the canes and only then the vision of the cones is impaired.

Skip to content