Usher Syndrome

Usher Syndrome 

What is Usher syndrome?

is a relatively rare genetic disorder caused by a mutation in any one of 10 genes that affects both hearing and vision

Photograph of the retina of a patient with Usher syndrome (left) compared to a normal retina (right). The optic nerve (arrow) looks very pale, the vessels (stars) are very thin and there is characteristic pigment, called bone spicules (double arrows)

There are three clinical types of Usher syndrome:

type 1, type 2, and type 3. In the United States, types 1 and 2 are the most common types

type 1

Children with type 1 Usher syndrome are profoundly deaf at birth and have severe balance problems. 

Vision problems most often begin with difficulty seeing at night, but tend to progress rapidly until the person is completely blind.

Type 2

Children with type 2 Usher syndrome are born with moderate to severe hearing loss and normal balance.

The vision problems in

type 2 Usher syndrome tend to progress more slowly than those in type 1, with the onset of RP often not apparent until the teens.

Type 3

Children with type 3 Usher syndrome have normal hearing at birth. Although most children with the disorder have normal to near-normal balance, some may develop balance problems later on.

Night blindness usually begins sometime during puberty. Blind spots appear by the late teens to early adulthood, and, by mid-adulthood, the person is usually legally blind.

How is Usher syndrome treated?

Currently, there is no cure for Usher syndrome. The best treatment involves early identification so that educational programs can begin as soon as possible. The exact nature of these programs will depend on the severity of the hearing and vision loss as well as the age and abilities of the person. Typically, treatment will include hearing aids, assistive listening devices, cochlear implants, or other communication methods such as American Sign Language; orientation and mobility training; and communication services and independent-living training that may include Braille instruction, low-vision services, or auditory training.

Some ophthalmologists believe that a high dose of vitamin A palmitate may slow, but not halt, the progression of retinitis pigmentosa. This belief stems from the results of a long-term clinical trial supported by the National Eye Institute and the Foundation for Fighting Blindness. Based on these findings, the researchers recommend that most adult patients with the common forms of RP take a daily supplement of 15,000 IU (international units) of vitamin A in the palmitate form under the supervision of their eye care professional. (Because people with type 1 Usher syndrome did not take part in the study, high-dose vitamin A is not recommended for these patients.)