Audiologic features of Norrie disease.
OBJECTIVE
Norrie disease is an X-linked recessive disorder in which patients are born blind and develop sensory hearing loss in adolescence. The hearing loss associated with Norrie disease has been shown in a genetically altered knockout mouse to involve dysfunction of the stria vascularis; most other structures are preserved until the later stages of the disease. The objective of this study was to characterize the audiologic phenotype of Norrie disease for comparison with the pathophysiologic mechanism.


METHODS
The design combined two series of clinical audiologic evaluations, with special attention to speech intelligibility.


RESULTS
The audiologic results for 12 affected individuals and 10 carriers show that patients with Norrie disease retain high speech intelligibility scores even when the threshold loss is severe.


CONCLUSIONS
The cochlear mechanism-- failure of the stria vascularis-- accounts for some of the higher values in the wide distribution of speech scores in cases with similar pure tone audiograms.
Halpin
Chris
C
Department of Otology and Laryngology, Harvard Medical School, Boston, Massachusetts, USA.
Owen
Grace
G
Gutiérrez-Espeleta
Gustavo A
GA
Sims
Katherine
K
Rehm
Heidi L
HL
D000328:Adult; D001301:Audiometry, Pure-Tone; D001309:Auditory Threshold; D001766:Blindness / Q000235:genetics; D002648:Child; D003051:Cochlea / Q000503:physiopathology*; D015834:Cochlear Diseases / Q000503:physiopathology*; D005260:Female; D006319:Hearing Loss, Sensorineural / Q000503:physiopathology*; D006801:Humans; D008297:Male; D013065:Speech Intelligibility