title: Comparative study of visual, auditory, and olfactory function in Usher syndrome.
abstract: BACKGROUND
  Usher syndrome is a genotypically and phenotypically heterogeneous group of autosomal recessive diseases featuring retinitis pigmentosa (RP) and sensorineural hearing loss. A general ciliary dysfunction has been suspected following reports of a mutated cytoskeletal protein (myosin VIIA) in type IB, and preliminary data has suggested an olfactory deficit. The purpose of this study was to quantitatively assess olfactory function in Usher syndrome patients and to search for a correlation between the degree of impairment of the three sensory systems as indication of an underlying ciliary defect.
  
  
  METHODS
  39 patients with Usher syndrome (8 type I, 31 type II) were examined. The ophthalmologic protocol included patient history, visual acuity, eye morphology, Goldmann perimetry, and electroretinography. The ENT protocol included a thorough examination, speech-recognition test, pure-tone audiometry and an olfactory function test.
  
  
  RESULTS
  In both groups, visual acuity was typically 20/40, the remaining visual field area was small, and the ERG responses were low to non-detectable. Average hearing loss was 100% in type I and 40% in type II. Olfactory thresholds were normal [median 9.7 (I) and 8.5 (II) vs. 8.5 in the control group]. There were multiple significant correlations between parameters of the same organ, but no relationship between parameters of different sensory systems.
  
  
  CONCLUSIONS
  Almost all Usher syndrome patients in this study had an advanced form of RP. In contrast, auditory function differed considerably between type I and type II. An impairment of the olfactory system could not be detected, and there was no correlation between parameters representing visual function, hearing ability, and olfactory sense.
authors: University Eye Hospital, Department II, Tübingen, Germany. see@uni-tuebingen.de
authors: M
authors: M
authors: Seeliger
authors: M
authors: M
authors: Pfister
authors: K
authors: K
authors: Gendo
authors: S
authors: S
authors: Paasch
authors: E
authors: E
authors: Apfelstedt-Sylla
authors: P
authors: P
authors: Plinkert
authors: H P
authors: HP
authors: Zenner
authors: E
authors: E
authors: Zrenner
mesh_terms: D000328:Adult; D001301:Audiometry, Pure-Tone; D004596:Electroretinography; D005260:Female; D005500:Follow-Up Studies; D006319:Hearing Loss, Sensorineural / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012174:Retinitis Pigmentosa / Q000175:diagnosis / Q000235:genetics / Q000503:physiopathology*; D012684:Sensory Thresholds; D012720:Severity of Illness Index; D012903:Smell; D013067:Speech Perception; D013577:Syndrome; D014792:Visual Acuity; D058609:Visual Field Tests; D014794:Visual Fields