Sensorineural hearing loss

Sensorineural hearing loss (SNHL) refers to deafness secondary to conditions affecting the inner ear, internal acoustic canal, cerebellopontine angle, or vestibulocochlear nerve.

Pathology

Conditions that cause sensorineural hearing loss can be divided by location:

• inner ear
  • bony labyrinth
    • otosclerosis (and other causes of otic capsule demineralization)
    • trauma, e.g. temporal bone fracture
    • congenital (developmental or acquired)
      • complete labyrinthine aplasia
      • cochlear aplasia
      • cochlear hypoplasia
      • common cavity malformation
      • incomplete partitioning
      • malformations of the vestibule or semicircular canals
      • large vestibular aqueduct syndrome
  • membranous labyrinth
    • infectious, e.g. labyrinthitis
      • can be complicated labyrinthine ossificans
    • trauma, e.g. intracochlear hemorrhage
    • intracochlear schwannoma
    • Meniere disease
• internal acoustic canal or cerebellopontine angle mass or vestibulocochlear nerve
  • vestibular schwannoma
  • meningioma
  • vascular (rare), e.g. hemangiomas
  • metastases: most commonly lung, breast, melanoma, lymphoma
  • cystic lesions, e.g. epidermoid cyst, arachnoid cyst
  • cochlear nerve anomalies 
  • superficial siderosis