Nystagmus (flickering eyes) is a disorder characterized by involuntary movements of the eyes – jitter from side to side, from top to bottom or in rotations. Nystagmus usually appears in both eyes, but sometimes only one eye can be injured. The main cause of nystagmus is decreased vision in early childhood for various reasons including albinism, iris deficiency, optic nerve degeneration, or retinal disease. The origin of nystagmus is hereditary. Some children are born with nystagmus. Others develop it at an early age of six to twelve weeks, or at a later stage.
Characteristics of nystagmus:
• Children with congenital nystagmus are unaware of the constant shift in their vision because their brain adapts to eye movements.
• Children with nystagmus tend to nod their head to concentrate, as the nodding somewhat compensates for eye movements.
• In order to achieve optimal vision, and reduce eye movement, children with nystagmus usually tilt their head in a certain direction – sideways, downwards or upwards. The "cancellation point" is able to locate even a toddler less than a year old.
Poor depth perception
Effects of nystagmus:
• Difficulty making eye contact.
• In many cases – a significant reduction in the quality of vision
• Increased fatigue, due to the extra effort involved in observation.
• There may be a negative effect on equilibrium, due to poor depth perception, which may make it difficult to use stairs or pass over unstable surfaces. Poor depth perception can also cause the child to be slower and more cumbersome than usual.
A child can be helped in his early years to get maximum use of his vision by providing many stimuli.
It is recommended to use games that encourage the child to follow a moving object, as well as use games that develop eye-hand contact. The child should be allowed to find the head position that best suits him. Children with nystagmus may need a longer time to identify things. The vision of children with nystagmus can vary during the day depending on their emotional state: when tired, irritable, or stressed, eye movements are more extreme, and the quality of vision is impaired. This disability cannot be cured, but vision function can be improved through appropriate and long-term treatment. There is rarely room for improvement in vision through surgery.