Related Experiment Videos
Audiologic features of Norrie disease
Chris Halpin1, Grace Owen, Gustavo A Gutiérrez-Espeleta
1Department of Otology and Laryngology, Harvard Medical School, Boston, Massachusetts, USA.
The Annals of Otology, Rhinology, and Laryngology
|September 2, 2005
Summary
Patients with Norrie disease (an X-linked disorder) maintain high speech intelligibility despite severe hearing loss. This suggests the stria vascularis dysfunction is key to their unique audiologic profile.
Area of Science:
- Genetics
- Ophthalmology
- Audiology
Background:
- Norrie disease is an X-linked recessive disorder causing blindness at birth and progressive sensory hearing loss.
- Hearing loss in Norrie disease is linked to stria vascularis dysfunction, as observed in knockout mouse models.
- Most cochlear structures remain unaffected until later disease stages.
Purpose of the Study:
- To characterize the audiologic phenotype in individuals with Norrie disease.
- To compare the audiologic findings with the known pathophysiologic mechanisms of the disease.
- To investigate the impact of stria vascularis dysfunction on hearing.
Main Methods:
- Clinical audiologic evaluations were conducted.
- Two series of evaluations were performed to ensure comprehensive data.
- Special attention was given to assessing speech intelligibility.
Main Results:
- Audiologic data were collected from 12 individuals affected by Norrie disease and 10 carriers.
- Patients with Norrie disease demonstrated high speech intelligibility scores.
- High speech intelligibility was observed even in the presence of severe pure-tone threshold hearing loss.
Conclusions:
- The cochlear mechanism, specifically stria vascularis failure, contributes to the observed speech score variations.
- Stria vascularis dysfunction explains higher speech intelligibility scores in some patients with similar audiograms.
- The findings highlight a distinct audiologic profile in Norrie disease related to specific cochlear pathology.