Prevalence of auditory neuropathy spectrum disorder in an auditory health care service.
Auditory neuropathy spectrum disorder (ANSD) is characterized by impairment of the auditory nerve associated with preservation of outer hair cell function.


OBJECTIVE
To establish the prevalence of ANSD in subjects with sensorineural hearing loss (SNHL).


METHODS
This retrospective study was carried out between 2010 and 2012 and included the charts of 2,292 individuals with SNHL. Data from otolaryngological and audiological examinations based on pure-tone and speech audiometry, impedance tests, otoacoustic emissions (OAEs), and brainstem auditory evoked potentials (BAEPs) were collected.


METHODS
presence of OAEs and/or cochlear microphonic (CM); absent or altered BAEPs, and normal MRI scans of the brain.


RESULTS
Twenty-seven (1.2%) of the 2,292 subjects with SNHL had ANSD (37% males; 63% females). Mild SNHL was seen in 29.6% of the individuals with ANSD; 55.5% had moderate SNHL; 7.4% had severe SNHL; and 7.5% had profound SNHL. In terms of age, 14.8% were aged between zero and 20 years, 44.1% were 41 to 60 years old, and 7.4% were above the age of 60.


CONCLUSIONS
ANSD was seen in 1.2% of the individuals with SNHL included in this study.
School of Medicine of Ribeirão Preto, University of São Paulo, Ribeirão Preto-SP, Brazil. rosimarpenido@usp.br
Rosimar Costa
RC
Penido
Myriam Lima
ML
Isaac
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D001301:Audiometry, Pure-Tone; D002648:Child; D002675:Child, Preschool; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D006313:Hearing Loss, Central / Q000150:complications* / Q000175:diagnosis / Q000453:epidemiology / Q000503:physiopathology; D006319:Hearing Loss, Sensorineural / Q000209:etiology* / Q000503:physiopathology; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D008875:Middle Aged; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology; D015995:Prevalence; D012189:Retrospective Studies; D012720:Severity of Illness Index