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