Dystonia is a type of movement disorder in which intentional actions can be erratic. It may involve muscles in any part of the body including the face. It is often associated with other signs and is usually progressive.
Signs and symptoms are usually noted early in the first decade of life. Abnormal facial movements and some stiffness in the lower limbs may be present and these are usually progressive. Some patients lose independent ambulation. Speech is commonly slurred (dysarthria) and swallowing difficulties may be present. Cognition and reasoning do not seem to be affected. MRI imaging may reveal abnormalities of structures at the base of the brain.
Most patients exhibit damage to the optic nerve which connects the eye to the brain and carries visual impulses that enable us to see. The reduction in vision often leads to abnormal eye movements, such as the to-and-fro motion of nystagmus.
The inheritance pattern in reported families is autosomal recessive. The clinically normal parents each carry one mutation in a specific gene and 25% of their offspring can be expected to inherit both mutations from them and exhibit this condition.
Optic nerve damage has been seen in infants as young as 15 months and may be congenital. This would most likely be diagnosed by an ophthalmologist or perhaps a neurologist. The movement abnormalities are most likely diagnosed by a neurologist. The signs and symptoms of movement coordination progressively worsen and can lead to significant physical challenges. Nothing is known regarding longevity.
No direct treatment is known but low vision aids and physical therapy might be helpful in dealing with the challenges of daily living.