Sammendrag
Auditory neuropathy (AN) is a relatively new diagnosis in which hearing is seriously abrupted by dys-synchronized nerve transmission. It is characterized by normal otoacoustic emissions or cochlear michrophonics, abnormal or absent auditory brainstem response and loss of middle ear muscle reflexes. Word-discrimination is often weakened, and it seems disproportional to the pure-tone audiogram. The pathology is not yet fully understood, but there seems to be a wide spectrum of predisposing risk-factors in which prematurity, hyperbilirubinemia and hypoxia are among the most common. There are several possibilities of lesions along the auditory pathway that could lead to abrupted nerve transmission to the auditory cortex. In contrast to common assumptions, AN is frequent and counts for about 10 % of new cases regarding severe sensory-neural hearing-loss. For infants at risk for hearing impairment the prevalence of AN has been reported to be at 0,2 % - 2 %. Among children with confirmed diagnosis of hearing-loss the prevalence is estimated to be 7 % – 15,4 %.
In this study, four cases of AN from The National Hospital, Oslo, are retrospectively reviewed and discussed. The sparsity of information and the uncertainty regarding options of treatment seem to be challenging for affected families. There is a global disagreement regarding the most suitable treatment of AN (auditory training, hearing aids or cochlear implants – CI). These cases illustrate the complexity pertaining diagnostics and how appropriate treatment can improve quality of life (case 3). This underlines the importance of acknowledging the diagnosis and treating individually and adequately.