Usher syndrome , also known as Hallgren syndrome , Usher—Hallgren syndrome , retinitis pigmentosa — dysacusis syndrome or dystrophia retinae dysacusis syndrome ,  is a rare genetic disorder caused by a mutation in any one of at least 11 genes resulting in a combination of hearing loss and visual impairment. It is a major cause of deafblindness and is at present incurable. Usher syndrome is classed into three subtypes I, II and III according to the genes responsible and the onset of deafness. All three subtypes are caused by mutations in genes involved in the function of the inner ear and retina. These mutations are inherited in an autosomal recessive pattern. The occurrence of Usher syndrome varies across the world and across the different syndrome types, with rates as high as 1 in 12, in Germany  to as low as 1 in 28, in Norway.
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Usher syndrome is an inherited disease that causes serious hearing loss and retinitis pigmentosa , an eye disorder that causes your vision to get worse over time. It is the most common condition that affects both hearing and vision. There is no cure. Tools such as hearing aids or cochlear implants can help some people.
Training such as Braille instruction, low-vision services, or auditory training can also help. Usher Syndrome. There are three types of Usher syndrome: People with type I are deaf from birth and have severe balance problems from a young age. Vision problems usually start by age 10 and lead to blindness.
People with type II have moderate to severe hearing loss and normal balance. Vision problems start in the early teens and get worse more slowly than in type I. People with type III are born with normal hearing and near-normal balance but develop vision problems and then hearing loss. Learn More. Clinical Trials. Usher Syndrome -- see more articles. Patient Handouts. Retinitis pigmentosa Medical Encyclopedia Also in Spanish.
What is Usher syndrome?
Usher syndrome is a condition characterized by partial or total hearing loss and vision loss that worsens over time. The hearing loss is classified as sensorineural, which means that it is caused by abnormalities of the inner ear. The loss of vision is caused by an eye disease called retinitis pigmentosa RP , which affects the layer of light-sensitive tissue at the back of the eye the retina. Vision loss occurs as the light-sensing cells of the retina gradually deteriorate. Night vision loss begins first, followed by blind spots that develop in the side peripheral vision.
Alternative titles; symbols. Other entities represented in this entry:. Usher syndrome type I is an autosomal recessive condition characterized by profound congenital hearing impairment with unintelligible speech, early retinitis pigmentosa usually evident within the first decade , and constant vestibular dysfunction. Type I is distinguished from type II on the basis of severity of hearing loss and the extent of vestibular involvement. Type I patients are profoundly deaf, whereas type II patients are 'hard of hearing. Patients with type IV USH4; have late onset of both retinitis pigmentosa and progressive, moderate to severe sensorineural hearing loss without vestibular involvement Khateb et al.
A perda auditiva pode ser classificada em leve dB , moderada dB , severa dB ou profunda acima de 81 dB. The patients were scheduled for tests of visual acuity, refraction, biomicroscopy, direct and indirect ophthalmoscopy, tonometry, retinography, visual field with Goldman perimeter and audiometry. Family's pedigree was built and an anamnesis and indirect binocular ophthalmoscopy of 63 sixty-three relatives were performed. All patients had retinitis pigmentosa, and tubular visual field.