SNHL is at least partially preventable by avoiding environmental noise, ototoxic chemicals and drugs, and head trauma, and treating or inoculating against certain triggering diseases and conditions like meningitis. Signs and symptoms
Since the inner ear is not directly accessible to instruments, identification is by patient report of the symptoms and audiometric testing. Of those who present to their doctor with sensorineural hearing loss, 90% report having diminished hearing, 57% report having a plugged feeling in ear, and 49% report having ringing in ear (tinnitus). About half report vestibular (vertigo) problems. For a detailed exposition of symptoms useful for screening, a self-assessment questionnaire was developed by the American Academy of Otolaryngology, called the Hearing Handicap Inventory for Adults (HHIA). It is a 25-question survey of subjective symptoms. Causes
Sensorineural hearing loss may be genetic or acquired (i.e. as a consequence of disease, noise, trauma, etc.). People may have a hearing loss from birth (congenital) or the hearing loss may come on later. Many cases are related to old age (age-related). Genetic
Hearing loss can be inherited. More than 40 genes have been implicated in the cause of deafness. There are 300 syndromes with related hearing loss, and each syndrome may have causative genes. Recessive, dominant, X-linked, or mitochondrial genetic mutations can affect the structure or metabolism of the inner ear. Some may be single point mutations, whereas others are due to chromosomal abnormalities. Some genetic causes give rise to a late onset hearing loss. Mitochondrial mutations can cause SNHL i.e.
For example, a hearing loss of 30 dB would make conversational speech sound more like a whisper. Causes
Only 10 to 15 percent of the cases diagnosed as SSHL have an identifiable cause. Most cases are classified as idiopathic, also called sudden idiopathic hearing loss (SIHL) and idiopathic sudden sensorineural hearing loss (ISSHL or ISSNHL) The majority of evidence points to some type of inflammation in the inner ear as the most common cause of SSNHL. Viral – The swelling may be due to a virus. A herpes type virus is believed to be the most common cause of sudden sensorineural hearing loss. The herpes virus lies dormant in our bodies and reactivates for an unknown reason. Vascular ischemia of the inner ear or cranial nerve VIII (CN8)
Perilymph fistula, usually due to a rupture of the round or oval windows and the leakage of perilymph. The patient will usually also experience vertigo or imbalance. A history of trauma is usually present and changes to hearing or vertigo occur with alteration in intracranial pressure such as with straining; lifting, blowing etc. Autoimmune – can be due to an autoimmune illness such as systemic lupus erythematosus, granulomatosis with polyangiitis

Treatment
Hearing loss completely recovers in around 35-39% of patients with SSNHL, usually within one to two weeks from onset. Eighty-five percent of those who receive treatment from an otolaryngologist (sometimes called an ENT surgeon) will recover some of their hearing.