Usher Syndrome Symptoms

Symptoms

 

Vision

People with Usher syndrome have a type of vision loss called retinitis pigmentosa (RP). In RP, the rod cells, that give night vision, are first to deteriorate, resulting in night blindness and low peripheral vision. The lack of peripheral vision can result in narrowing of a visual field, or ‘tunnel vision’. The cone cells, that give colour and central vision, are next to degrade. RP is a progressive condition, meaning that vison will gradually decrease over time.
 

Hearing

Hearing loss can be present at birth in children with Usher syndrome or hearing loss develops shortly after. The onset of hearing loss differs between different types of Usher syndrome. Of all people with congenital bilateral, sensorineural hearing loss, it is estimated that at least ten percent have Usher syndrome.
 

Balance

Balance is a result of coordinated sensory input from eyes, the vestibular organs in the inner ear and the sensory systems of the body, such as the skin, muscles and joints. The vestibular organs are dysfunctional in Usher syndrome and result in balance issues.

Severity of Symptoms

 

Usher Type I

Usher type I causes deafness from birth and early childhood signs of RP. While cochlear implants may be of use, this form of deafness may be so severe that hearing aids may not be of use and individuals with Usher type I may not develop intelligible speech. Balance is often affected in those with type I and can slow the development of sitting or walking in children.

 

Usher type II

Individuals with Usher type II have less severe early onset hearing loss than those with type I and so affected children will benefit from hearing aids and develop intelligible speech. RP tends to present at the later age of teenage years in those with Usher type II and balance problems are not usually found.

 

Usher Type III

Usher type III is the rarest form. Hearing at birth is usually normal but is lost during late childhood and becomes worse over time, with most middle aged individuals with type III having profound hearing loss. RP begins to develop by teenage years and continues to progress. Balance problems are experienced by some people with type III.