Nystagmus is a disorder of the eyes that causes involuntary and repetitive movements of your eyes. Symptoms range from a slow rhythmic movement to rapid involuntary jerking.
Nystagmus is considered a part of the vestibular system and results from damage in the inner ear or abnormal brain stem responses.
Hereditary nystagmus can be caused by a mutation of the MYOC gene on the chromosome. This is an autosomal dominant disorder, meaning a person only needs one mutated gene copy to get the disease. In contrast, two mutated copies are needed for a full expression.
If you as a parent have hereditary nystagmus, there is a 50/50 chance you will pass it on to your offspring. A person with hereditary nystagmus most likely has two mutated copies of MYOC, one copy from each parent. You can learn more by scheduling an eye exam with eye doctor chandler.
Symptoms of Nystagmus:
The symptoms of hereditary nystagmus include:
When hereditary nystagmus occurs, different phases determine the intensity of the nystagmus.
The first phase is during birth, where the movement is triggered by an imbalance of cerebrospinal fluid levels or a loss of tone in the muscles that execute eye movements.
This phase can last for up to 3 months to 4 years.
The second phase is the developmental phase, where the nystagmus is most prominent. The eyes move in a wide circle and can better record movement.
The third stage is the stationary phase. The nystagmus becomes relatively stable and may stay constant even after being observed for up to ten years. This phase also persists after reaching adulthood, with most cases continuing into adulthood.
This phase lasts up to fifty years of age in most cases.
In the fourth phase, known as the paradoxical phase, nystagmus occurs in a wide movement, with the eyes moving in small circles and outward from a central point. Usually, this is not as prominent as the third stage of nystagmus. Your child will spend most of time at school and in school activities.
The fifth stage is the pathological phase. It is the last stage of nystagmus and occurs after reaching adulthood. The nystagmus becomes exaggerated and resembles a large circle in size, moving towards a central point. This can be mild or severe. Mostly it persists to adulthood without progression.
Causes of Nystagmus:
The cause of hereditary nystagmus is a mutation in the MYOC gene. This gene takes part in a critical role in regulating the movement of the eyes during development. When this gene is disrupted, one will get an abnormally fast or slow movement of the eyes from birth to adulthood.
When a person becomes pregnant, many changes occur to their bodies, including the fluid levels in their ear structures. This fluid allows the pressure in their ear to be adjusted when the head moves, balancing it with the body. The MYOC gene plays the main role in regulating that pressure balance.
In hereditary nystagmus, one or both copies of the MYOC gene are mutated. This results in a lack of regulation of cerebrospinal fluid levels and a huge imbalance, which causes the eyes to move faster and more erratically than usual from birth into adulthood.
Treatment of Nystagmus:
There is currently no cure for hereditary nystagmus, and it is impossible to eliminate its symptoms even with surgery completely. Usually, the treatment given depends on the severity of the symptoms and whether one becomes disabled or not.
The main goal of treatment is to reduce symptoms or prevent them from getting worse as time progresses. The treatments are not curative, and the goal is to reduce the severity and impact of symptoms on their daily lives.
Management of nystagmus in adults:
The management of nystagmus in adults determines the severity of the symptoms and considers some lifestyle adaptations that one may need.
One should be aware that medications are not very effective, and most are just used to reduce symptoms.
Some treatments provided include medication, OT, PT, and surgery. Medication can be used if it causes sleepiness or tiredness; if it is not taken during the daytime, increasing the dosage can help with reducing nystagmus symptoms.
In conclusion, hereditary nystagmus is a disorder that causes the eyes to move in a circular motion and is usually present since birth. Some cases can be very mild, while other cases will cause people to be disabled. The main goal of treatment is to lessen symptoms or prevent you from getting worse as time progresses. The treatments are not curative, and the goal is to reduce the severity and impact of symptoms on your daily lives.