Eye Condition Fact Sheet
Condition
Usher Syndrome
Description
Usher syndrome is an inherited condition which results in hearing loss and a progressive loss of vision from Retinitis pigmentosa (RP) a degenerative condition of the retina, and usually appears during adolescence or early adulthood. RP can occur without hearing loss. The condition is named after a British ophthalmologist, C.H. Usher, who in a paper in 1914described several cases in which the link between congenital deafness and RP was stressed. Other names for Usher syndrome include Hallgren syndrome, Usher-Hallgren syndrome, rp-dysacusis syndrome and dystrophia retinae dysacusis syndrome.
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).
Parts of visual system affected/Effects on the conditions of visual system
There are at least three different forms of Usher syndrome.
Usher syndrome type 1 (USH1)
People with Usher syndrome type 1 (USH1) are born completely deaf and experience problems with balance.
Usher syndrome type 2 (USH2)
In Usher syndrome type 2 (USH2), newborns have moderate to severe hearing impairment.
A rarer third type of Usher syndrome (USH3) was documented in 1995.
Children with USH3 are usually born with good or only mild impairment of hearing. Their hearing and vision loss is progressive, starting around puberty. Balance may be affected.
Treatments
Currently, there is no cure for Usher syndrome. The best treatment involves early identification so that educational programs can begin as soon as possible. Researchers found that vitamin A palmitate can slow retinal degeneration in some people with RP and Usher syndrome type 2.
Is condition congenital, adventitious, progressive or stable?
Usher is transmitted genetically by an autosomal recessive gene. To produce a child with Usher both parents must carry the recessive gene. Autosomal implies that the gene is not sex linked and so both males and females are equally affected by the condition. In recessive inheritance both parents carry the gene, but are not aware that they are carriers until the condition is diagnosed in their children. The child with Usher syndrome has two recessive genes for the trait and will transmit these genes to their offspring.
Anticipated functional implications of the condition
This syndrome is characterized by deafness and a gradual vision loss. The hearing loss is associated with a defective inner ear, whereas the vision loss is associated with retinitis pigmentosa (rp), a degeneration of the retinal cells. Special tests such as electronystagmography (ENG) to detect balance problems and electroretinography (ERG) to detect retinitis pigmentosa help detect Usher syndrome early.Furthermore, symptoms of Usher Syndrome may vary on an individual basis for each patient. Only your doctor can provide adequate diagnosis of symptoms and whether they are indeed symptoms of Usher Syndrome.
References