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الرحيم الرحمن الله بسم
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
• 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 or
mixed hearing loss
Good speech discrimination
Age
Lifestyle and occupation
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 with less
vestibulocochlear side effects
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