The usher syndrome (US) is an autosomal recessive disorder characterized by congenital bilateral sensorineural hearing loss and progressive visual loss secondary to retinitis pigmentosa. It is the most common cause of the hereditary combined
deafness-blindness in the western world. Three different types of US are recognized by clinical criteria. The US type Ⅰhas severe to profound hearing loss, vestibular dysfunction, and prepubertally diagnosed retinitis pigmentosa, while the US
type
Ⅱhas moderate to severe hearing loss, normal vestibular function, and later onset of retinitis pigmentosa. The US type Ⅲhas a progressive hearing loss and retinitis pigmentosa with variable vestibular involvement. The diagnosis is confirmed by
medical
history and thorough otoscopical, audiologic, vestibular, and ophthalmolgical examinations. We have recently experienced a case of the US type Ⅰ and report this with a brief review of the related literature.
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