OTOSCLEROSIS

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Transcript OTOSCLEROSIS

‫بسم هللا الرحمن الرحيم‬
OTOSCLEROSIS
DEFINITION
A primary disease of the otic capsule
characterized pathologically by abnormal
resorption and deposition of bone
HISTOPATHOLOGY
• Resorption of bone by
osteocytes
• Formation of new vascular
spongy bone
• Formation of dense sclerotic
bone
AREAS OF PREDILECTION
Fissula ante fenestram (80% to 90%)
OTHER AREAS
• Round window, the apex of
the cochlea, the
cochlear aqueduct, the semicircular canals, and
the stapes footplate itself
COCHLEAR INVOLVEMENT
ETIOLOGY
• Unknown cause
• Positive family history in about 60%
• Inherited by autosomal dominant transmission
with incomplete penetration (60%)
• Persistent measles virus infection
– Detection of measles virus RNA in the affected bone
– Detection of measles virus-specific antibodies in the
perilymph
PHYSIOLOGY
• Conductive HL: due to fixation of the
stapedial footplate
• Mixed HL: due to
– Liberation of toxic metabolites into the inner
ear
– Vascular compromise from sclerosis and
narrowing of vascular channels
– Direct extension of lesions into the inner ear
• Cochlear otosclerosis
Involvement of footplate and cochlea
CLINICAL PRESENTATION
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Hearing loss of gradual onset at 15 - 45 years
Slowly progressive course
70% are bilateral
Accelerates with pregnancy (30-40%)
Tinnitus
Paracusis Willisii
Change of the speech pattern
Vestibular symptoms
PHYSICAL EXAMINATION
• Normal tympanic membrane
• Schwartze sign (Flamingo flush)
PHYSICAL EXAMINATION
• Normal tympanic membrane
• Schwartze sign (Flamingo flush)
• Tuning fork tests
PURE TONE AUDIO
CARHART’S NOTCH
• Decrease in bone conduction thresholds
• 5 dB at 500 Hz
• 10 dB at 1000 Hz
• 15 dB at 2000 Hz
• 5 dB at 4000 Hz
• Explanation is not known
• Reverses following successful surgery
AUDIOMETRY
• Pure tone audiogram
• Speech discrimination
AUDIOMETRY
• Pure tone audiogram
• Speech discrimination
• Impedence & tympanometry
CT SCAN
Double ring cochlea or Halo’s sign
COCHLEAR OTOSCLEROSIS
Isolated pure sensorineural hearing loss
without a conductive component
CRITERIA FOR DIAGNOSIS OF
COCHLEAR OTOSCLEROSIS
• Progressive pure cochlear loss beginning at the
usual age of onset for otosclerosis
• Unilateral conductive hearing loss consistent with
otosclerosis and bilateral symmetric SNHL
• Positive Schwartze’s sign
• Positive family history
• Excellent discrimination
• Stapedial reflex demonstrating the “on-off effect”
• CT: demineralization of the cochlea
DIFFERENTIAL DIAGNOSIS
• Congenital fixation of the stapes
• Middle ear effusion
• Chronic OM and ossicular
discontinuity
• Tympanosclerosis
• Malleus head fixation
• Systemic diseases
SYSTEMIC DISEASES
• Osteogenesis imperfecta
– Stapes fixation
– Blue sclera
– Fractures
SYSTEMIC DISEASES
• Osteogenesis imperfecta
– Stapes fixation
– Blue sclera
– Fractures
• Pagets disease
– Crowding in epitympanum
– Elevated alkaline phosphatase
– Skeletal bone involvement
TREATMENT
• Observation
• Hearing aid
• Medical treatment
• Surgical treatment
OBSERVATION
INDICATIONS OF
OBSERVATION
• Unilateral
• Mild CHL
• Young age
HEARING AID
INDICATIONS OF HEARING AID
• Refuse surgery
• Poor surgical candidate
• Following improvement of CHL
MEDICAL TREATMENT
AIM OF MEDICAL TREATMENT
• Stabilize the disease by reduction of the
osteoclastic bone resorption and increase
osteoblastic bone formation
MEDICAL MANAGEMENT
• Sodium fluoride: 50-75 mg /day/2years
followed by 25 mg for life
• Vitamin D
• Calcium carbonate
INDICATIONS
• Cochlear otosclerosis
• Patients with confirmed otosclerosis but
having progressive SNHL disproportionate
to age
CONTRAINDICATIONS
• Chronic nephritis
• Rheumatoid arthritis
• Pregnancy and lactation
• Children
SURGICAL TREATMENT
PATIENT SELECTION FOR
SURGICAL TREATMENT
 Socially
unacceptable
conductive
mixed hearing loss
 Good speech discrimination
 Age
 Lifestyle and occupation
or
ABSOLUTE CONTRAINDICATION
OF SURGERY
The better or the only functioning ear
OTHER
CONTRAINDICATIONS
• ? Patients experience frequent changes in
barometric pressure
• “Malignant” otosclerosis
• Endolymphatic hydrops
• TM perforation
• Infections
STAPES SURGERY
Stapedectomy
Stapedotomy
STAMP
(STApedotomy
Minus Prosthesis) or
Stapedioplasty
STAPEDECTOMY
• Results probably are the best
• More traumatic to the inner ear
– Increased post-op vestibular symptoms
– Higher incidence of postoperative SNHL
• The operation is unavoidable in:
– Comminuted fracture of the footplate
– Revision surgery
STAPEDOTOMY
• Equal
or
better
results
vestibulocochlear side effects
with
less
COMPARISON
STAMP
• Preservation of the stapedius
tendon
– Reduction in hyperacusis
– Reduction in risk for long-term
postoperative inner ear injuries
• No prosthesis complications
• Very difficult technique
SURGICAL PROCEDURE
The Incision
Permeatal (Transcanal)
Endaural
STAPEDOTOMY
LASER STAPEDOTMY
STAMP
OPERATIVE PROBLEMS &
COMPLICATIONS
TM PERFORATION
• Proceed and then repair
CHORDA TYMPANI INJURY
• 30% of cases
• Metallic taste
• Symptoms usually resolves
in 3-4 months
• More symptoms if bilateral
OBTRUSIVE FACIAL NERVE
• 0.5 %
• Stapedotomy is usually possible
BLEEDING
• Mucosal trauma
• Active phase
• Persistent stapedial artery
Persistent stapedial artery
ROUND WINDOW
OTOSCLEROSIS
• About 1% complete (Shuknecht)
• If complete:
Abandon surgery
• If incomplete or not sure:
Do not remove bone and
proceed
OBLITERATIVE OTOSCLEROSIS
OF THE OVAL WINDOW
• A total stapedectomy
is
contraindicated
because of high risk
of surgically induced
SNHL
INCUS PROBLEMS
• Subluxation:
Proceed
• Dislocation:
Remove incus & use a
malleus-grip prosthesis
FLOATING FOOTPLATE
• May be avoided if control
holes are used or by using
laser fenestration
FLOATING FOOTPLATE
• May be extracted by needles/hooks with hole
inferior to the oval window
FLOATING FOOTPLATE
• In many cases should be left
and surgery is completed
with unpredictable results or
use laser fenestration
MALLEUS ANKYLOSIS
• About 0.5%
• May be congenital or acquired
• Causes about 15-20 dB CHL
Remove malleus head and the incus and
use malleus grip prosthesis
CSF GUSHER
• Due to fundal defect of IAM or widened cochlear
aqueduct
• Introduce spinal catheter and proceed
Or
• Pack with fascia and gauze for 4-5 days with
delayed reconstruction that avoid reopening the
fenestra
PERILYMPH FISTULA
• Primary or secondary
PREVENTION OF PERILYMPH
FISTULA
• Stapedectomy < stapedotomy
• Oval window seal
• No fat or gel-foam for seal
• Prohibit nose blowing, flying, diving, &
lifting heavy objects postoperatively
DIAGNOSIS OF PERILYMPH
FISTULA
• Drop or fluctuation in hearing
• Vertigo & tinnitus
• Audiometry
• ENG
• Fistula test
• Radiology
TREATMENT
• Surgical closure
REPARATIVE GRANULOMA
• Granuloma formation around the prosthesis
and incus
• 1-5%
• Gradual deterioration 5-15 days
postoperativly
• Vertigo, tinnitus and deafness
• Otoscopy: reddish discoloration of the
posterior TM
REPARATIVE GRANULOMA
• Treatment is by emergency
tympanotomy and excision
SNHL
• 0.2-10%
• Serous labyrinthitis high frequencies
• Surgical trauma
PERSISTENCE OR
RECURRENCE OF CHL
• Prosthesis malfunction
• Fibrous adhesion
• Incus erosion
PERSISTENCE OR
RECURRENCE OF CHL
• Prosthesis malfunction
• Fibrous adhesion
• Incus erosion
• Missed pathology: e.g. malleus fixation,
round window otosclerosis
• Otosclerosis regrowth
RARE COMPLICATIONS
• Facial paralysis
• Acute otitis media
• Cholesteatoma
THANK YOU