title: Auditory neuropathy: endocochlear lesion or temporal processing impairment? Implications for diagnosis and management.
abstract: OBJECTIVE
  Auditory neuropathy/dys-synchrony, characterized by absent auditory brainstem responses, normal otoacoustic emissions or cochlear microphonics, and word discrimination disproportional to the pure-tone audiogram, may be accompanied by perceptual consequences that could jeopardize language acquisition in affected children. However, the related evidence is constantly changing leading to a serious debate. The aim of the present paper is to review the current knowledge on auditory neuropathy/dys-synchrony, and to present the therapeutic strategies that can be employed in its management, taking into account the potentially underlying pathophysiology.
  
  
  METHODS
  Literature review from Medline and database sources. Related books were also included.
  
  
  METHODS
  Controlled clinical trials, prospective and retrospective cohort studies, nested-based case-control and analytical family studies, laboratory and electrophysiological studies, animal models, case-reports, joint statements and review articles.
  
  
  RESULTS
  Auditory neuropathy/dys-synchrony, in contrast to what is widely believed, is a very frequent disease, responsible for approximately 8% of newly diagnosed cases of hearing loss in children per year. Hyperbilirubinemia and hypoxia represent major risk factors, whereas generalized neuropathic disorders, or a genetic substrate involving the otoferlin gene, are responsible for the phenotype of auditory neuropathy/dys-synchrony in certain cases. Auditory nerve myelinopathy and/or desynchrony of neural discharges are the most probable underlying pathophysiologic mechanisms. Genetic testing may be helpful in cases of non-syndromic prelingual children. Auditory neuropathy/dys-synchrony management aims at restoring the compromised processing of auditory information, either through conventional amplification and/or alternative forms of communication, or by cochlear implantation (combined with intensive speech and language therapy).
  
  
  CONCLUSIONS
  Auditory neuropathy/dys-synchrony is more frequent than considered in the past, especially amongst hearing-impaired children. Accurate diagnosis, based on subjective and objective hearing assessment techniques (including the various electrophysiological assessment measures), and timely treatment of the affected children is of paramount importance, with hearing aids, intensive speech and language therapy (and sign language when indicated) providing the mainstay of habilitation, and cochlear implantation representing a valid therapeutic alternative.
authors.affiliation: ENT Department, Hippokrateion General Hospital of Athens, 114 Vas. Sofias Avenue, Athens, 11527, Athens, Greece. pevlast@hotmail.com
authors.forename: Petros V
authors.initials: PV
authors.lastname: Vlastarakos
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Nikolopoulos
authors.forename: Evangelia
authors.initials: E
authors.lastname: Tavoulari
authors.forename: George
authors.initials: G
authors.lastname: Papacharalambous
authors.forename: Stavros
authors.initials: S
authors.lastname: Korres
mesh_terms: D019929:Cochlear Implantation; D003055:Cochlear Microphonic Potentials; D003056:Cochlear Nerve / Q000503:physiopathology*; D016057:Evoked Potentials, Auditory, Brain Stem; D006311:Hearing Disorders / Q000175:diagnosis* / Q000209:etiology* / Q000503:physiopathology / Q000628:therapy; D006801:Humans; D017084:Otoacoustic Emissions, Spontaneous; D013063:Speech Discrimination Tests; D013067:Speech Perception