Visual impairment on a cortical background is a neurological impairment, and the damage is cerebral rather than ocular. It is a temporary or permanent condition created as a result of impaired nerve conduction to the visual center, causing difficulties and inconsistencies in the procedures for absorbing, processing and deciphering visual information.
The degree of neurological injury depends on the time of the injury, as well as the location and intensity of the injury.
There are two types of cortical visual impairment
Congenital: Children born with brain damage whose impairment in the center of vision is one of its components.
Acquired : As a result of an accident – many of the cases are reversible and curable.
There are several causes of CVI (cortical visual impairment), but the main one is a reduction in the blood supply to the brain – HYPOXIA ISCHEMIA.
Other causes: accumulation of fluid in the brain, epilepsy, meningitis, trauma, hemorrhage in the brain.
• The eyes of a child with CVI look normal.
• Inconsistency in visual function.
• Tendency to look at an object with the help of the peripheral field of view, rather than the central field of view.
• Due to difficulty in distance vision, a tendency to bring the object closer to their eyes due to the need to isolate the object from the background, which makes it easier for them to process the visual information.
• Compulsively looking at a light source.
• Children with CVI usually recognize colors.
• Difficulty in hand-eye coordination.
• Difficulty in separating a character from a background, which is manifested in a lack of proper decoding, lack of vision of details and difficulty in hand-eye coordination in performing motor tasks.
• Some children look at an object for a moment and turn their head when reaching out.
• Spontaneous vision loss.
• Delay in visual response to visual stimulus.
• Preference for a particular field of view.
Preference for clear objects or toys.
• Sometimes impaired reflex to threatening movement and touch on the bridge of the nose.
• Difficulty integrating between sight and hearing.
The prognosis for cortical blindness varies. Many times following a focused intervention in functional vision, and following a general improvement in the various areas of development, there may be a significant improvement in functional vision.
Ways to help a child with cortical vision:
The main goals in treating children with CVI are to achieve maximum use of visual remnants, improve functional vision, and allow the child to learn from the environment. The more the child improves his visual ability, the greater his ability to focus on the stimulus.
• To improve the child's responses, the visual environment must be stimulated.
• Controlled exposure to stimuli.
• Exposure to stimuli while transmitting simple, regular and predictable information.
• Create a color contrast.
• Use of objects familiar to the child from everyday life.
• The object must be used again and again many times, as this gives the child confidence.
• Work in very short periods of a single number of minutes.
• The child should be allowed a long time to observe, so that he can respond to what he has seen.
• Vestibular activity (movement, swing, ball, walking) increases the ability to see, so it is recommended to perform some motor activity before vision stimulation treatment.