Sudden sensorineural hearing loss and delayed complete sudden spontaneous recovery

This is a case report of a 53-yr-old female who experienced sudden sensorineural hearing loss (SSNHL) accompanied by roaring tinnitus in her right ear. The patient's hearing partially improved in the low frequencies in response to intratympanic injections. Given that her hearing loss did not improve further, the patient was fitted with a hearing aid to mask the tinnitus and restore a sense of balance between the two ears. Approximately 9 mo postonset of the SSNHL, a complete spontaneous recovery of hearing occurred. Such a delayed and complete recovery is highly unusual. This case highlights that the spontaneous recovery in hearing indicates that the pathological cause for the SSNHL involved a process that was capable of repair or regeneration, thus ruling out pathologies related to cochlear hair cell destruction or nerve fiber loss. This leaves a possibility that the event causing the onset of the SSNHL resulted in a disruption of the ion homeostatic properties of the cochlea via the production of the endocochlear potential.