1. Acoustic Neuroma & Glomus Tympanicum
Dr. Vishal Sharma

2. Acoustic Neuroma

3. Introduction A.K.A.: vestibular schwannoma / neurilemmoma
Benign, encapsulated, slow growing tumour
arising from Schwann cells of superior vestibular
division of 8th nerve within internal auditory canal
Rarely from inferior vestibular or cochlear division

4. Tumour growth Tumor expansion within internal auditory canal
 causes widening & erosion of I.A.C.
 appears in cerebello-pontine angle (> 2.5 cm)
 involves 5th, 7th, 9th, 10th, 11th cranial nerves
 displacement of brainstem & cerebellum
 raised intracranial pressure
 Involvement of 6th & 3rd cranial nerves

5. Classification as per size
1. Intra-canalicular: confined to I.A.C.
2. Small: up to 1.5 cm
3. Medium: 1.5 to 4 cm
4. Large: over 4 cm

6. Tumor size

7. Intra-canalicular

8. Small

9. Medium

10. Large

11. Epidemiology 10% of all brain tumors
80% of all Cerebello-pontine angle tumors
Age: yrs
Male : Female = 3:2
Unilateral (90%); Bilateral (10%)
Bilateral = von Recklinghausen’s
neurofibromatosis

12. Clinical Staging Otological stage: due to pressure on 8th nerve
Other Cranial nerve involvement
Brainstem + Cerebellar involvement
Raised intra-cranial tension
Terminal stage: failure of vital centers of brainstem & cerebellar tonsil herniation

13. Otological symptoms & signs
Progressive, unilateral sensorineural deafness
Poor speech discrimination (disproportionate)
Tinnitus
Mild vertigo
Nystagmus
Vestibular symptoms appear late due to slow tumor growth & vestibular compensation

14. Other Cranial nerve palsy
Trigeminal: first nerve to be involved
Loss of corneal reflex
Pain, numbness and paresthesia of the face
Facial:
Hypoaesthesia of posterior external auditory canal wall (Hitselberger’s sign)
Facial weakness, Loss of taste, ed lacrimation

15. Other Cranial nerve palsy
Glossopharyngeal, Vagus & Accessory Spinal:
Dysphagia
Hoarseness
Nasal regurgitation
Decreased gag reflex
Abducent & Oculomotor:
Diplopia

16. Brainstem involvement
 Ataxia  Weakness of arms & legs  Tendon
reflexes exaggerated
Cerebellar involvement
 Ataxic gait (fall on affected side)  Intention
tremors  Past-pointing  Dysdiadochokinesia
Increased Intra-cranial tension
 Headache  Projectile vomiting  Blurred vision
 Papillodema  Abducent nerve palsy

17. First Symptoms Hearing loss: 80-100 % Vertigo: 10-50 %
Tinnitus: %
Ear ache: %
Sudden hearing loss: 5%
Facial paralysis: %

18. Investigations Pure Tone Audiometry: high frequency SNHL
Speech audiometry: SD scores < 30%
Tone decay test: positive
Stapedial Reflex: Decay > 50 % in 10 sec
B.E.R.A.: wave V >4.2 ms; inter-wave V >0.2 ms
Caloric test: I/L canal paresis or no response
C.T. scan with contrast: for tumor > 0.5 cm
M.R.I. with gadolinium contrast: best

19. Pure Tone Audiogram

20. Speech Audiometry
Roll over phenomenon

21. Calorigram

22. Brainstem Evoked Response Audiometry (B.E.R.A.)

23. Contrast C.T. Scan

24. Contrast M.R.I.: neuro-anatomy

25. Contrast M.R.I. : intra-canalicular

26. Contrast M.R.I. : small

27. Contrast M.R.I. : Medium

28. Contrast M.R.I. : Large

29. Bilateral tumor: small

30. Bilateral tumor: large

31. Treatment 1. Observation 2. Microsurgical removal: (partial or total)
Trans-labyrinthine approach
Retro-sigmoid or Sub-occipital approach
Middle Cranial Fossa approach
Combined approach
3. Proton Stereotactic Radiotherapy
4. Brainstem Implant: after B/L tumor excision

32. Observation Indications:
Age > 60 years with small tumor & no symptoms
Tumour in only hearing / better hearing ear
Serial MRI used to follow growth pattern.
Treatment recommended if hearing is lost or tumor size becomes life threatening.

33. House Ear Institute 1977

34. Incisions
Middle cranial fossa
Retro-sigmoid
Trans-labyrinthine

35. Retro-sigmoid Approach

36. Sub-occipital approach

37. Trans-labyrinthine approach

38. Middle cranial fossa approach

39. Surgical Approach Protocol
1. Intra-canalicular: Middle cranial fossa approach
2. Small (<1.5 cm): Retrosigmoid approach
3. Medium ( cm)
a. Hearing fine**: Retrosigmoid approach
b. Hearing bad: Trans-labyrinthine approach
4. Large (>4 cm): Trans-labyrinthine / Combined
** Pure Tone Average < 30 dB, S.D. Score >70%

40. Intra-operative photograph

41. Proton stereotactic radiotherapy
Single high dose of radiation delivered on a small area to arrest or kill tumor cells. Minimal injury to surrounding nerves & brain tissue
Gamma Knife: radioactive cobalt LINAC X-knife: linear accelerator Cyber-Knife: robotic radio-surgery system
Indication: 1. Surgery refused / contraindicated 2. Post-operative residual tumour

42. Treatment Planning

43. Treatment Planning

44. P.S.R.T. in progress

45. Pre & Post treatment

46. Glomus Tumours

47. Introduction Synonym:  Chemodectoma  Non-chromaffin paraganglioma
Commonest benign tumour of middle ear
derived from glomus bodies distributed along
parasympathetic nerves of head & neck
Consists of paraganglionic cells derived from
embryonic neuroepithelium

48. Introduction Histologically benign but locally invasive, highly
vascular, non-encapsulated, slow growing tumors
10 % tumors: familial
10 % tumors: multicentric
10 % tumors: functional (secrete catecholamines)
4 % tumors: metastatic

49. Histopathology
Typical cellular groups ("Zellballen") surrounded by a capillary network

50. Types Glomus jugulare Arises along jugular bulb & superior vagal
Ganglion, near floor of middle ear
Glomus tympanicum
Arises along tympanic plexus on promontory
formed by tympanic branch of Glossopharyngeal
nerve, near medial wall of middle ear

51. Spread

52. Common Symptoms Seen in 40-60 yrs Female : male = 5:1
U/L deafness: progressive, conductive
Pulsatile tinnitus: synchronous with pulse
decreases on carotid occlusion
Blood stained otorrhoea
Ear ache & vertigo: rare

53. Signs Rising sun sign: red reflex on otoscopy
Browne’s pulsation sign on siegalization: Positive pressure  tumor engorges  tumor blanches  pressure released  tumor engorges
Aural mass: bleeds on touch
Systolic bruit: over mastoid on auscultation
Neurological: 9th, 10th 11th cranial nerve palsy

54. Rising sun sign

55. Blood-stained otorrhoea

56. Bleeding polyp

57. Investigations 1. Pure Tone Audiometry: Conductive deafness
2. High resolution C.T. scan with contrast:
erosion of carotico-jugular spine (Phelp’s sign)
3. Magnetic Resonance Imaging with Gadolinium contrast: for soft tissue & intra-cranial extension
4. M. R. Angiography: non-invasive. For invasion of Internal jugular vein & internal carotid compression

58. Investigations 5. Digital Subtraction Angiography
6. Four Vessel Angiography
 Tumour blush
 Feeding arteries
 Contra lateral circulation
 Embolization (within 48 hours of surgery)
 Other carotid body tumors

59. Investigations
7. 24 hour urine Vanillyl Mandelic Acid level: > 7 mg  Catecholamine secreting tumor  Initial hypertension during surgery followed by hypotension
8. Careful biopsy of mass in ext. auditory canal: rule out malignancy. Ear packing done for profuse bleeding.

60. C.T. scan plain
Glomus Jugulare

61. Plain & contrast C.T. scan

62. M.R.I. with contrast

63. 4 Vessel Angiography

64. Digital Subtraction Angiography

65. Pre & Post embolization

66. Magnetic Resonance Angiography

67. Fisch Staging Stage A: tumor limited to middle ear cleft
Stage B: tympano-mastoid tumor sparing
infra-labyrinthine bone
Stage C: tympano-mastoid tumor eroding
Stage D1: Intra-cranial extension < 2 cm
Stage D2: Intra-cranial extension > 2 cm

68. Surgical Treatment Anterior Tympanotomy: small stage A
Extended facial recess approach: large stage A
Modified Radical Mastoidectomy: small Stage B
Combined Modified Radical Mastoidectomy + Fisch’s Infratemporal fossa approach:
large stage B, Stage C
Subtotal temporal bone resection: Stage D1

69. Anterior Tympanotomy

70. Infratemporal fossa approach

71. Facial nerve decompression

72. Facial nerve re-routing

73. Tumor excised

74. Other Treatments
Tele - Radiotherapy (4000 – 5000 rads) or Stereotactic Radiotherapy:
Inoperable, residual or recurrent tumors;
Pt unfit for surgery or refuses surgery
Observation: Pt > 70 yr with minimal symptoms
Embolization:
Before surgery: reduces vascularity
After RT: for residual or recurrent tumor

75. Thank You