Otoscelrosis

1. DR. L.ABINAYA
FIRST YEAR POST GRADUATE,
DEPARTMENT OF ENT
SVMCH & RC,
PUDUCHERRY
OTOSCLEROSIS

2. CONTENTS:
1. Developmental Anatomy
2. Definition otosclerosis / otospongiosis
3. Etiology of otosclerosis
4. sites, types of otosclerotic involvement
5. Diagnose a patient with otosclerosis
6. Differential diagnosis for otosclerosis
7. Investigations & interpretations
8. Treatment of otosclerosis

3. DEVELOPMENTAL ANATOMY
• otic placodes

4. DEVELOPMENTAL ANATOMY(CONT..)
• otic vesicle, otocyst
• The semicircular
canals, utricle, saccule,
and cochlea - are
fashioned by modelling
of the otic vesicle.

5. DEVELOPMENTAL ANATOMY(CONT..)
• otic capsule
• This cartilaginous
envelope which
surrounds the
nervous elements
of the embryo's
inner ear
subsequently
ossifies to form
bony labyrinth

7. Definition
oto, meaning “of
the ear,” and
sclerosis, meaning
“abnormal
hardening of body
tissue.”
7

8. Definition of otosclerosis /
otospongiosis:
• Otosclerosis is a genetically-mediated
primary metabolic bone disease of the otic
capsule in which the normal dense
enchondral layer of otic capsule is replaced by
irregularly laid focus/foci of spongy bone
• Fixation of the ossicle
• conductive or mixed hearing loss

10. ETIOLOGY
• Exact cause not known.
• Heredity: Family history of deafness is present in 50% of
cases.
• Sex: females are affected twice as often as males.
• Age of onset: usually occurs between 20-30 years of age.
• Pregnancy: Otosclerosis may be initiated or aggravated by
pregnancy but never caused by it.

12. • Viral.
– Electron micro: viral nucleocapsids in cells of
otospongiotic lesions
– Immunohistochemical: measles virus
nucleocapsid protein in cells associated with
otospongiosis.(McKenna 1986)
– Polymerase chain reaction (PCR) : anti-measles
IgG in the perilymph of patients with otosclerosis

14. Most common sites of
involvement
• Anterior oval window niche / fissula ante
fenestrum (80-90%)

15. OTHER AREAS
• Round window niche (30-50%)
• Apical medial wall of the cochlea
• Posterior to the oval window
• Posterior internal auditory canal
• Primary footplate
• Semicircular canals

16. Pathophysiology
Normal bone is absorbed and replaced by vascular spongy osteoid
tissue
Bone become thicker and less vascular
Fixes the stapes
Prevents vibration of ear bones in response to sound waves
Conductive deafness
Spread to foot plates of stapes
Affect bony capsule of the labyrinth
Results in sensory neural deafness

17. Types of otosclerosis
1. Stapedial
2. Cochlear
3. Mixed
4. Histologic / asymptomatic

18. Types of stapedial
otosclerosis
1. Anterior focus
2. Posterior focus
3. Circumferential focus
4. Biscuit type (thick plate)
5. Obliterative type

21. Histiologic stages
1. Early or spongiotic phase
(otospongiosis)
2. Late or sclerotic phase

22. 1.Early or spongiotic phase
(otospongiosis)
 Osteolytic resorption of bone
develops a spongy appearance. It
causes vascular dilation bone surrounding
blood vessels.
 “Schwartze's sign”.

24. Blue mantle

25. 2. Late or sclerotic phase
 Dense sclerotic bone forms in
the areas of previous resorption.

26. COCHLEAR OTOSCLEROSIS:
 The otosclerotic process proceeds upon the
membranous labyrinth producing sensory-
neural deafness.

27. MIXED OTOSCLEROSIS:
 Otosclerosis causes both fixation of the
stapes as well as involvement of the labyrinth
– mixed hearing loss.

28. Epidemiology
• Gender
– Histologic otosclerosis – 1:1 ratio
– Clinical otosclerosis – 2:1 (W:M)
• Age
– 15-45 yrs most common age range of presentation

29. Diagnosis
of Otosclerosis

30. History
• Most common presentation
– Women age 20 - 30
– Conductive or Mixed hearing loss
• Slowly progressive,
• Bilateral (80%)
• Asymmetric

31. History
– Tinnitus (75%) – cochlear / active
– ParacusisWillisi- better hearing in noisy
environment
– Speech : monotonous, soft
 Family history
 2/3 have a significant family history
 Particularly helpful in patients with severe or profound
mixed hearing loss

32. History
 History of ear infections
 Vestibular symptoms
 25%
 Most commonly dysequilibrium
 Occasionally attacks of vertigo with rotatory
nystagmus

33. Physical Exam
 OTOSCOPY
 Most helpful in ruling out other disorders
 Middle ear effusions
 Tympanosclerosis
 Tympanic membrane perforations
 Cholesteatoma or retraction pockets
 Superior semicircular canal dehiscence

35. Differential Diagnosis
1. Secretory otitis media
2. Chronic adhesive otitis media
3. Tympanosclerosis
4. Ossicular discontinuity
5. Congenital stapes fixation
6. Malleus head fixation (fixed malleus-incus
syndrome)
7. Congenital cholesteatoma
8. CSF otorrhoea
9. Paget’s disease
10. Osteogenesis imperfecta

43. Type A represents normal middle ear function. Type
A curves have normal mobility and pressures and
typify normal hearing and sensorineural hearing loss
with normally functioning middle ear systems.

44. Type As represents normal middle ear pressure but
reduced mobility suggesting limited mobility of the
tympanic membrane and middle ear structure,
commonly seen in fixation of the ossicular chain.

47. Imaging
 Computed tomography (CT) of the temporal
bone
 Proponents of CT for evaluation of otosclerosis
 Pre-op
 Characterize the extent of otosclerosis
 Severe or profound mixed hearing loss
 Evaluate for enlarge cochlear aqueduct
 Post-op
 Recurrent CHL
 Re-obliteration vs. prosthesis dislocation
 Vertigo

50.  a transverse CT-image
showing a subtle
otosclerotic focus in
the characteristic site:
the fissula ante
fenestram (arrows).

51. There is a lucency
anterior to the oval
window (arrow) and
between the cochlea
and the internal
auditory canal.
This is combined
fenestral and
retrofenestral
otosclerosis

52. otosclerosis on both sides

53. • a patient with a
well-positioned
metallic
stapedial
prosthesis:
medially it
touches the oval
window and
laterally it
connects with
the long process
of the incus.
Notice the lucency between vestibule and
cochlea as a manifestation of otosclerosis
(arrow).

54. Management
 Medical
 Hearing aid
 Bone anchored hearing aid
 Surgery

55. Medical
• SODIUM FLUORIDE
– Mechanism
– Fluoride ion replaces hydroxyl group in bone
forming fluorapatite
– solid solution with hydroxylapatite [Ca5(PO4)3OH]
in biological matrices >> hard crystalline solid
[Ca5(PO4)3F ]
– Resistant to resorption
– Increases calcification of new bone
– Causes maturation of active foci of otosclerosis

56. Medical
 SODIUM FLUORIDE
 Reduces tinnitus, reverses Schwartze’s sign, resolution of
otospongiosis seen on CT
 Dose – 20-120mg
 Indications
 Non-surgical candidates
 Patients who do not want surgery
 Surgical candidates with + Schwartze’s sign
 Treat for 6 months pre-operatively
 Post-op. if otospongiosis detected intra-op.

57. Medical
 SODIUM FLUORIDE
 Hearing results
 50% stabilize
 30% improve
 Re-evaluate q 2 yrs with CT and for Schwartze’s
sign to resolve
 If fluoride are stopped – expect re-activation
within 2-3 years

58. contraindications
1. Chronic renal disease
2. Chronic rheumatoid arthritis
3. Pregnancy/lactation
4. Allergy to flouride
5. Skeletal flurosis
6. children

59. Medical
 BISPHOSPHONATES
 Class of medications that inhibits bone resorption by
inhibiting osteoclastic activity
 Studies conducted on otosclerosis patients with
neurotologic symptoms report the majority of
patients with subjective improvement or resolution.
 Future application of this treatment unclear, especially
with new reports of bisphosphonate related
osteonecrosis.

60. HEARING AID
Indication:
- Non-surgical candidates
- Patients who do not desire surgery
- Following improvement of CHL
- Patients with conductive and sensorineural
hearing loss greater than 25db.

61. BAHA
 Indicated for conductive and mixed hearing
loss as well as for single sided deafness.
 Only hearing ear with otosclerosis combined
with difficulty using a conventional aid, or a
post – fenestration cavity.

63. Surgery
 Best surgical candidate
 Previously un-operated ear
 Good health
 UnacceptableAir-Bone Gap
 25 to 40 dB
 Negative Rinne test
 Excellent speech discrimination (>60%)
 Desire for surgery

64. Surgery
 Poor factors for surgery
 Age of the patient
 Elderly(>70yrs) & general medical diseases
 Poorer results in the high frequencies
 Congenital stapes fixation (44% success rate)
 Juvenile otosclerosis (82% success rate)
 Occupation
 Divers / Pilots / Airline steward/stewardess

65. Surgery
• Other factors
– Vestibular symptoms
• Meniere's disease
– Concomitant otologic disease
• Cholesteatoma
• Tympanic membrane perforation /CSOM /ASOM
– Positive schwartze sign (active focus/cochlear
otosclerosis)
– Only hearing ear
– Poor ET function

68. Canal Injection
 2-3 cc of 1% lidocaine
with 1:50,000 or
1:100,000 epinephrine
 4 quadrants
 Bony cartilaginous
junction

69. Raise Tympanomeatal Flap
 6 and 12 o’clock
positions
 6-8 mm lateral to the
annulus
 Take into account
curettage of the
scutum

88.  First laser stapedotomy performed by Perkins
in 1978
 Less trauma to the vestibule
 Less incidence of prosthesis migration
 Less fixation of prosthesis by scar tissue

89. Drill Fenestration
 0.7mm diamond burr
 Motion of the burr
removes bone dust
 Avoids smoke
production
 Avoids surrounding heat
production

90. Laser Fenestration
 Laser
 Avoids manipulation of the footplate
 Argon and Potassium titanyl phosphate (KTP/532)
 Wave length 500 nm
 Visible light
 Absorbed by hemoglobin
 Surgical and aiming beam
 Carbon dioxide (CO2)
 10,000 nm
 Not in visible light range
 Surgical beam only
 Requires separate laser for an aiming beam (red helium-neon)
 Ill defined fuzzy beam

95. PROSTHESIS SELECTION

96. Total Stapedectomy
 Uses
 Extensive fixation of the footplate
 Floating footplate
 Disadvantages
 Increased post-op vestibular symptoms
 More technically difficult
 Increased potential for prosthesis migration

101. Oval window seal
 Tragal perichondrium
 Vein (hand or wrist)
 Temporalis fascia
 Blood
 Fat
 Gelfoam (now discouraged)

103. Special Considerations
and Complications in
Stapes Surgery

104. 1. Overhanging Facial Nerve
2. Floating Footplate
3. Diffuse Obliterative Otosclerosis
4. Perilymphatic Gusher
5. Narrow oval window
6. TM tear
7. Persistent stapedial artery

105. Overhanging Facial Nerve
 Usually dehiscent
 Consider aborting the procedure
 Facial nerve displacement (Perkins, 2001)
 Facial nerve is compressed superiorly with No. 24
suction (5 second periods)
 10-15 sec delay between compressions
 Perkins describes laser stapedotomy while nerve is
compressed
 Wire piston used
 Add 0.5 to 0.75 mm to accommodate curve around the
nerve

107. Floating Footplate
 Footplate dislodges from the surrounding
OW niche
 Incidental finding
 More commonly iatrogenic
 Prevention
 Laser
 Footplate control hole
 Management
 Abort
 H. House favors promontory fenestration and
total stapedectomy
 Perkins favors laser fenestration

108. Diffuse Obliterative
Otosclerosis
 Occurs when the
footplate, annular
ligament, and oval
window niche are
involved
 Closure of air-bone gap
< 10 dB less common.
 Refixation commonly
occurs

109. Perilymphatic Gusher
 Associated with patent cochlear aqueduct
 More common on the left
 Increased incidence with congenital stapes
fixation
 Increases risk of SNHL
 Management
 Rough up the footplate
 Rapid placement of the OW seal then the prosthesis
 HOB elevated, stool softeners, bed rest, avoid
Valsalva, +/- lumbar drain

110. Round Window Closure
 20%-50% of cases
 1% completely
closed
 No effect on
hearing unless
100% closed
 Opening has a
high rate of SNHL

111. Persistent stapedial artery
 Found in 1.6 out of 5000 cases.
 The procedure should be aborted.

115. COMPLICATIONS OF STAPES
SURGERY

116. COMPLICATIONS
1. Immediate severe SNHL
2. Delayed SNHL
3. Perilymph fistula
4. Reparative Granuloma
5. Ossicular (incus) necrosis / displacement /
disarticulation >> COHL

117. SNHL
 1%-3% incidence of profound permanent SNHL
 Surgeon experience
 Extent of disease
 Cochlear
 Prior stapes surgery
 Temporary
 Serous labyrinthitis
 Reparative granuloma
 Permanent
 Suppurative labyrinthitis
 Extensive drilling
 Basilar membrane breaks
 Vascular compromise
 Sudden drop in perilymph pressure

118. Reparative Granuloma
• Granuloma formation around the prosthesis and
incus
• 2 -3 weeks postop
• Initial good hearing results followed by an increase in
the high frequency bone line thresholds
• Associated tinnitus and vertigo
• Exam – reddish discoloration of the posteriorTM
• Treatment
– ME exploration
– Removal of granuloma
• Prognosis – return of hearing with early excision
• Associated with use of Gelfoam

119. Vertigo
 Most commonly short lived (2-3 days)
 More prolonged after stapedectomy
compared to stapedotomy
 Due to serous labyrinthitis
 Medialization of the prosthesis into the
vestibule
 With or without perilymphatic fistula
 Reparative granuloma

120. Recurrent Conductive Hearing
Loss
 Slippage or displacement of the prosthesis
 Most common cause of failure
 Immediate
 Technique /Trauma
 Delayed
 Slippage from incus narrowing or erosion
 Adherence to edge of OW niche
 Stapes re-fixation
 Progression of disease with re-obliteration of OW
 Malleus or incus ankylosis

124. THANK YOU