acoustic nerve injury

The auditory nerve is composed of the cochlear nerve and the vestibular nerve, which together pass through the internal auditory canal to the inner ear, so they are often damaged simultaneously, manifesting as symptoms in both hearing and balance. Although the two are different components of the same nerve, their responses to etiological factors are not entirely consistent. Factors affecting the auditory nerve include noise, pressure, disease, and genetics. The damage of sound to hearing is mainly divided into two types: one is sudden loud noise, such as firecrackers; the other is chronic noise, where prolonged work under high noise levels causes imperceptible hearing damage. Stress is likely to cause sudden deafness, a type of sensorineural hearing loss, often presenting as sudden hearing loss in one ear, possibly accompanied by tinnitus, a feeling of fullness in the ear, and so on. Medications can also affect the auditory nerve. Otitis media, acoustic neuroma, otosclerosis, and other conditions are diseases that can directly lead to hearing loss; with early treatment, most people can avoid deafness. In addition, 50% of deafness is hereditary, meaning congenital auditory nerve damage with a genetic basis. Patients with auditory nerve injury often present with tinnitus, a sensation of blockage in the external auditory canal, and hearing loss, especially poor perception of high-pitched sounds; this type of deafness is called neural deafness or sensorineural deafness. Patients presenting with balance disorders experience vertigo, nausea, and vomiting, and may show vagal stimulation symptoms such as pallor and excessive sweating.