Sensorineural hearing loss in patients with cerebral palsy after asphyxia and hyperbilirubinemia

The location of lesions causing hearing loss in patients with cerebral palsy due to asphyxia or neonatal hyperbilirubinemia has remained unclear. We performed behavioral audiometry, distortion product otoacoustic emission (DPOAE) and auditory brainstem evoked response (ABR) in six patients with cerebral palsy due to asphyxia or neonatal hyperbilirubinemia in order to determine the lesion location causing their hearing impairment. In all cases, behavioral audiometry revealed a threshold elevation of 50-75 dB and ABR were no response. DPOAE were totally absent in five patients and normal in one patient. Our study suggests that lesions causing hearing loss potentially include the organ of Corti especially at the outer hair cells and the cochlear nerve.