Patient will present as → a 42-year-old male with a history of neurofibromatosis type II complains of nausea, vomiting, headache, continuous disequilibrium, and a slowly progressive unilateral hearing loss in his right ear. On physical exam, the patient has decreased sensation to touch on the right side of this face. An MRI is performed with results seen here.
An acoustic neuroma (a.k.a. vestibular schwannoma) is a benign tumor of the Schwann cells (the cells which produce myelin sheath) – most commonly affect the vestibular division of the 8'th cranial nerve
- Patients will present with an insidious unilateral hearing loss, tinnitus, headache, facial numbness, continuous disequilibrium
- Increased incidence in patients with neurofibromatosis type II
- Unilateral hearing loss +/- vertigo
Definitive diagnosis is by MRI (Gold standard)
- An audiogram is the first test done during a physical examination to diagnose acoustic neuroma. It usually reveals an asymmetric sensorineural hearing loss and a greater impairment of speech discrimination than would be expected for the degree of hearing loss.
- Such findings indicate the need for imaging tests, preferably gadolinium-enhanced MRI.
Small or non-growing tumors can be observed with serial MRI scans
- Stereotactic radiation therapy tends to be used for patients who are elderly, those with smaller tumors, or those who cannot undergo surgery for medical reasons.
- Microsurgery can involve a hearing-preservation approach (middle cranial fossa or retrosigmoid approach) or a translabyrinthine approach if there is no useful residual hearing.
Question 1 |
Rinne air conduction greater than bone conduction; Weber lateralizes to left. Hint: See B for explanation | |
Rinne air conduction greater than bone conduction; Weber lateralizes to right. | |
Rinne bone conduction greater than air conduction; Weber lateralizes to right. Hint: In conductive hearing loss, the Rinne will result in bone conduction greater than air conduction and Weber will lateralize ipsilaterally. | |
Rinne bone conduction greater than air conduction; Weber lateralizes to left. Hint: In conductive hearing loss, the Rinne will result in bone conduction greater than air conduction and Weber will lateralize ipsilaterally. |
References: Merck Manual · UpToDate