Management of unilateral vestibular schwannoma/acoustic neuroma

• Published in: New Zealand medical journal Vol. 120; no. 1265; p. U2805
• Main Authors: Bird, Philip A, MacFarlane, Martin R
• Format: Journal Article
• Language: English
• Published: New Zealand Pasifika Medical Association Group (PMAG) 09.11.2007
• Subjects: Gamma rays; Hospitals; Humans; Medical Oncology - methods; Neuroma, Acoustic - diagnosis; Neuroma, Acoustic - therapy; Neurosurgical Procedures - methods; Otology; Radiation therapy; Radiosurgery - methods; Surgery; Tumors
• ISSN: 1175-8716

The growth of these tumours in the IAC and out into the CPA means that the order of involvement or neural and intracranial structures (and therefore the clinical course) is reasonably predictable--viz: an initial period of silent growth -> loss of function of the vestibular nerve of origin and then the associated ipsilateral vestibular nerve, with subtle affects on balance; compression of the ipsilateral cochlear nerve in the IAC -> gradual hearing loss (sensorineural) and variable tinnitus; pressure on the trigeminal nerve -> ipsilateral facial numbness (hypoaesthesia and hypoalgesia); gradual pressure on the cerebellum and pons -> increasing ataxia and ipsilateral cerebellar signs; significant pressure on and stretching of the facial nerve -> progressive facial paresis/palsy; significant pressure on and stretching of the glossopharyngeal and vagal nerves -> hoarse voice and progressive difficulties with swallowing -> aspiration; obstruction to CSF outflow from the 4th ventricle -> hydrocephalus, and finally coma and death from a combination of aspiration pneumonia and raised intracranial pressure with coning. Surgery is generally performed by two surgeons, one an otolaryngologist trained in skull base surgery and the other a neurosurgeon also experienced in such surgery.\n An important feature in the assessment and best practice management of patients with VS is that it be undertaken by a team involving both neurosurgeon and otolaryngologist both trained and proficient in the surgical techniques necessary in operating on these tumours.