Usher Syndrome (cont.)
What are the characteristics of the three types of Usher syndrome?
Type 1
Children with type 1 Usher syndrome are profoundly deaf
at birth and have severe balance problems. Many of these children obtain little
or no benefit from hearing aids. Parents should consult their doctor and other
hearing health professionals as early as possible to determine the best
communication method for their child. Intervention should be introduced early,
during the first few years of life, so that the child can take advantage of the
unique window of time during which the brain is most receptive to learning language, whether spoken or
signed. If a child is diagnosed with type 1 Usher syndrome early on, before he
or she loses the ability to see, that child is more likely to benefit from the
full spectrum of intervention strategies that can help him or her participate
more fully in life's activities.
Because of the balance problems associated with type 1
Usher syndrome, children with this disorder are slow to sit without support and
typically don't walk independently before they are 18 months old. These children
usually begin to develop vision problems in early childhood, almost always by
the time they reach age 10. 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. Although the severity of
hearing loss varies, most of these children can benefit from hearing aids and
can communicate orally. 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. Hearing and sight worsen
over time, but the rate at which they decline can vary from person to person,
even within the same family. A person with type 3 Usher syndrome may develop
hearing loss by the teens, and he or she will usually require hearing aids by
mid- to late adulthood. 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.
|
Usher Syndrome: Type 1, 2, and 3 |
| |
Type 1 |
Type 3 |
Type 3 |
| Hearing |
Profound deafness in both ears from birth |
Moderate to severe hearing loss from birth |
Normal at birth; progressive loss in childhood or early teens |
| Vision |
Decreased night vision before age 10 |
Decreased night vision begins in late childhood or teens |
Varies in severity; night vision problems often begin in teens |
| Vestibular function (balance) |
Balance problems from birth |
Normal |
Normal to near-normal, chance of later problems |
Next: How is Usher syndrome diagnosed? »
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