Diagnosis

Acoustic neuroma

Etiology

Causes

• Conductive hearing loss: cerumen, foreign body, neoplasm, swelling/stenosis of the canal, Perforated tympanic membrane, Ossicular discontinuity, Otosclerosis, Fluid, scarring.

• Sensorineural hearing loss: Neuronal damage by intense noise, barotrauma, viral infection, ototoxic drugs (aminoglycosides), Presbyacusis, Iatrogenic, Temporal bone fracture, Meningitis, Cochlear otosclerosis, Menieres disease, Acoustic neuroma.

Pathophysiology

• Tumor growth occupy the cerebellopontine angle of the internal auditory canal and gradually compresses vestibular fibers on the surface

Complications [4tk]

• Injury to the inferior cerebellar arteries

• Neurological injury

• Brain herniation

• Brain hemorrhage

• Injury to the cerebellum

• Facial paralysis

• Hearing loss

Risk factor

• Exposure to high-dose ionizing radiation

• Associated with neurofibromatosis types I and II

Epidemiology

Incidence per 100.000 [9rn][4tk]

Approach

• Otoscopy

• Weber test

• Rinne test

• Audiogram

• CT caput

• Biopsy

Treatment

Over a 5-year period, ~50% of tumors grow with a risk of hearing loss

1. Observation with imaging/audiologic evaluation (elder patients, small/asymptomatic tumors) [5oq][4tk]

2. Stereotactic radiosurgery

3. Surgical removal

Differential diagnoses

Arachnoid cyst, Arteriovenous malformation, Cerumen, Cholesteatoma, Cholesterol cyst, Craniopharyngioma, Dermoid Cyst, Ependymoma, Epidermal cyst, Facial neuroma, Foreign body, Glioma, Granuloma, Hamartoma, Hemangioma, Lipoma, Lymphoma, Meniere disease, Meningioma, Meningitis, Otitis media, Otosclerosis, Pituitary adenoma, Presbyacusis