Usher syndrome is the most common syndrome affecting both hearing and vision, and is the leading cause of deafblindness (having no hearing or vision).
There are three types of Usher syndrome, and types I and II are further divided into subtypes. The three types are characterized by severity and age of onset, but the genes that cause each of these types also vary. In general, Usher syndrome is characterized by hearing loss caused by problems in the development of the inner ear and progressive vision loss caused by Retinitis pigmentosa (RP) (See: Retinitis pigmentosa). The hearing loss in Usher syndrome may be apparent at birth (type I and II), or not develop until later in childhood (type III). The vision loss takes longer to develop and may be noticeable before age 10 (type I) or not until later in childhood (types II and III). This vision loss caused by RP affects night vision first, then peripheral vision resulting in blind spots or tunnel vision. Cataracts (a clouding of the lens) have also been reported. The vision loss may progress to the point of blindness, but many retain some vision. The individual may also have problems with balance due to the same inner ear problem that affects their hearing.
Diagnosis of Usher syndrome requires a physical examination and genetic testing. There is no cure for Usher syndrome at this time, but there are various treatment options available. Hearing aids, cochlear implants, and other devices are available to manage hearing loss. There are also options to slow the progression of vision loss. It is important to talk to your child's doctor immediately if you notice any changes in hearing or vision. If your child has been diagnosed with Usher syndrome, talk to your doctor to find the most current treatment options.