Usher Syndrome
Usher syndrome is an inherited condition that affects both hearing and vision. It is the most common cause of combined deafness and blindness in Canada and worldwide. The condition results from mutations in genes involved in the function of hair cells in the cochlea and photoreceptor cells in the retina. There are three main clinical subtypes.
Type I involves profound hearing loss from birth, vestibular dysfunction (balance problems), and early onset of retinitis pigmentosa (a progressive deterioration of the retina) beginning in childhood or adolescence. Type II presents with moderate to severe hearing loss from birth, relatively normal balance, and vision changes that develop later. Type III features progressive hearing loss and variable vestibular function, with vision loss that develops later in adulthood.
Genetic counseling is recommended for affected individuals and families. Hearing management may include hearing aids or cochlear implants depending on the degree of hearing loss. Ongoing ophthalmological monitoring is important given the progressive nature of the retinal degeneration.
