Sudden sensorineural hearing loss

Sudden sensorineural hearing loss (SSNHL) is defined as a loss of hearing of 30 dB or more over at least three contiguous frequencies. Usually, symptoms present unilaterally and suddenly within 24-72 h. As the majority of patients (30-65 %) with unilateral sudden SNHL report spontaneous recovery within 2 weeks, unilateral disease is mostly regarded as a benign condition. Prognosis for recovery is dependent on a number of factors, including patient age, presence of vertigo at onset, degree of hearing loss, and time between onset of hearing loss and treatment. The pathology of sudden SNHL remains unclear. However, a series of factors, including viral infections, microcirculatory disorders, autoimmune disorders, and labyrinthine hemorrhage, have been proposed as causative factors. Different treatment regimens like antioxidants, corticosteroids, vasodilators, hyperbaric oxygen (HBO), or carbogen therapy have been described. Among these approaches, steroid treatment is the most common.