Post on 27-Nov-2014
ACOUSTIC NEUROMA
Vestibular schwannomas are benign, encapsulated tumors that arise from schwann cells of vestibular nerve
Most of vestibular schwannomas originate in the region of the internal auditory canal
Constitutes 80% of all CP angle tumors and 10% of all brain tumors
Cerebellopontine angle
Vestibular schwannoma
Classification
Growth of tumorClassification- Intracanalicular Small (upto 1.5 cm) Medium (1.5 to 4 cm) Large (over 4 cm)
Vestibular schwannoma
• Origin-Schwann cells of vestibular nerve
Vestibular schwannoma
Clinical Features:-
Age and sex. 40 to 60 years
Progressive unilateral sensorineural hearing loss
Tinnitus
Difficulty to understand speech
Vertigo/imbalance
Cranial nerve involvement
Brainstem involvement
Cerebellar involvement
Vestibular schwannoma
Acoustic neuroma
Clinical Features
Vestibular schwannoma
Investigations:
Pure tone audiometry
Speech audiometry
Recruit phenomenon
SISI Index
Threshold tone decay test
Caloric test
RADIOLOGICAL TESTS; Plain x-rays
CT Scan
Vestibular schwannomaM R I SCAN
Tests to differentiat cochlear from retro cochlear pathology
Tests Normal Cochlear Retro cochlear
PTA Normal S.N.loss S.N.loss
S.D.S 90 to 100% Below 90% poor
Recruitment absent present absent
SISI score 0 to 15% >70% 0 to 205
TDT 0to 15 dB <25 dB > 25 dB
SR Normal normal abnormal
BERA Normal abnormal abnormal
Vestibular schwannoma
• Differential Diagnosis
Vestibular schwannoma
TREATMENT
• Careful serial observation.
• surgical excision of the tumor
• Arresting tumor growth using stereotactic radiation therapy