Otosclerosis

Dr. Vishal Sharma

Definition

• Hereditary disease of bony labyrinth showing

replacement of lamellar enchondral bone by

irregularly laid new bone.

• New bone is spongy + more vascular in active

Otospongiosis but thicker & more cellular in

inactive Otosclerosis.

Antonio Valsalva

First described

ankylosis of stapes

in 1741

Adam Politzer

Coined the term

Otosclerosis

in 1893

Friedrich Siebenmann

Coined the term

Otospongiosis

in 1912

Epidemiology• Exact etiology is unknown (? Viral)

• Autosomal dominant: variable penetrance

• Race: common in white races & Indians

• Female : Male = 2 : 1

• Age: Common in 20 - 40 years

• Hormonal influence: es in pregnancy,

menopause, stress (trauma, surgery)

Van der Hoeve syndrome Otosclerosis + osteogenesis imperfecta +

blue sclera

Types of Otosclerosis

A. Stapedial

B. Cochlear: otosclerotic focus is seen over

Round window Promontory

C. Stapedial + cochlear: mixed type

D. Malignant: rapidly progressing cochlear

lesion with severe sensori-neural deafness.

Types of Stapedial Otosclerosis1. Anterior focus (commonest): 2 mm anterior to oval

window. 2. Posterior focus: 2 mm behind oval window.

3. Circumferential: involves footplate margin only.

Types of Stapedial Otosclerosis

4. Biscuit type: footplate involved, margin is free.

5. Obliterative: obliterates oval window completely.

Symptoms of Otosclerosis

1. Deafness: Bilateral, slowly progressive

Conductive: stapedial otosclerosis

Sensori-neural: cochlear otosclerosis

Mixed: stapedial + cochlear otosclerosis

2. Soft, modulated, monotonous voice

3. Tinnitus & vertigo: in cochlear lesion

Symptoms of Otosclerosis4. Paracusis Willisii: Pt has better hearing in noisy

surroundings (people increase their voice intensity

& pt’s speech discrimination becomes better).

Thomas Willis (1621-1675)

Otoscopy

Normal T.M. is seen in

most cases. Pinkish

colour over promontory

seen in otospongiosis

(2 - 10 % cases)

Schwartze sign /

Flamingo pink blush.

Tuning Fork TestsRinne Weber A.B.C.

Stapedial Negative (BC > AC)

Lateralizes toDeaf ear

Normal

Cochlear Positive (AC > BC)

Lateralizes to Better ear

Decreased

Mixed Negative (BC > AC)

Lateralizes to Better ear

Decreased

Gelle & Bing TestsVibrating tuning fork placed over mastoid & then:

External auditory canal is blocked in Bing test or

E.A.C. pressure ed by Siegalization in Gelle test

Bing Gelle

Otosclerosis No change No change

Normal / SNHL Intensity es Intensity es

Pure Tone Audiometry• Low frequency conductive deafness

• Carhart’s notch in bone conduction at 2 KHz

Carhart’s notch• Proposed theories

1. Stapes fixation disrupts normal ossicular

resonance (2000 Hz)

2. Normal compression mode of bone

conduction is disturbed because of relative

perilymph immobility

3. Mechanical artefact

• Carhart’s notch reverses with stapes surgery

Speech Audiometry

Speech Discrimination Score (maximum score

achieved) is almost 100 %.

Speech Reception Threshold (intensity at which

50 % words are heard) is increased by the

amount of conductive hearing loss.

Speech Audiometry

Impedance Audiometry

• As curve seen in 40 %

cases of otosclerosis.

• Normal middle ear

pressure + decreased

middle ear compliance.

• Others have A curve.

Stapedial reflex present

Stapedial reflex absent

C.T. scan temporal bone

200 coronal oblique cuts are taken

Stapedial otosclerosis (coronal)

Cochlear otospongiosis (axial)

Differential Diagnosis

• Otitis Media with Effusion: type B tympanogram

• Adhesive Otitis Media: absence of T.M. mobility

• Tympanosclerosis: white patch on T.M.

• Ossicular discontinuity: type Ad tympanogram

• Congenital ossicular chain fixation: tympanotomy

• Malleus head fixation: tympanotomy

History of development of stapes surgery

Stapes mobilization: Kessel (1880), Rosen (1952)

Lateral semicircular canal fenestration: Holmgren

(1923), Sourdille (1932), Lempert (1938)

Complete Stapedectomy: Jack (1893), Shea (1956)

Partial Stapedectomy (posterior 1/3): Plester (1960)

Stapedotomy: Shea (1962), Marquet (1965)

Laser Stapedotomy: Perkins & Di Bartolomeo (1980)

Johannes Kessel

Samuel Rosen

Gunnar Holmgren

Maurice Sourdille

Julius Lempert

John J. Shea Jr.

Inclusion criteria for surgery

• Pure Tone Average between 30 - 60 dB

• Air bone gap > 15 dB

• Speech discrimination score > 60 %

• Absence of sensorineural deafness

Contraindications for surgery

Only hearing ear Meniere’s disease

Otitis media Otitis externa

Extremes of age Pregnancy

Professions: divers, high construction workers,

frequent travelers, noisy surroundings

Surgical steps for

Stapedotomy

Right T.M. (upright)

Right T.M. (supine)

Per-meatal Incision

Tympanomeatal flap raised

Bony overhang curetted

Bony overhang curetted

Chorda tympani preserved

Chorda tympani separated

Confirm footplate fixation

Checking for absence of round window reflex

Depth measurement prosthesis

Incudo-stapedial joint broken

Footplate perforation made

Fenestration with burr

Posterior crus fractured

Teflon piston

• Length of piston =

medial surface of

incus to stapes

footplate + 0.25 mm

• Range = 3.75 – 4.25

mm

1

cm

Piston placed in perforation

Stapedius tendon cut

Stapedius tendon cut

Piston crimped around incus

Anterior crus fractured

Stapes superstructure removed

Footplate perforation sealed

Tympanomeatal flap put back

Laser Stapedotomy

Stapedius vaporization

Footplate fenestration

Rossette formation

Stapedotomy Piston

Stapedectomy

Footplate Fenestration

Stapes superstructure removed

Footplate removal

Prosthesis placed over vein graft

Complications of stapes surgery

Intra-operative Post-operative

Floating footplate Otitis media

Submerged footplate Oval window granuloma

Dislocated incus Perilymph fistula

Perforated TM Sensori-neural HL

Damage to facial nerve Persistent air-bone gap

or chorda tympani Vestibular dysfunction

Persistent stapedial artery Delayed facial palsy in

Perilymph flooding laser surgery

Sodium Fluoride• Given in cochlear otosclerosis & active focus

of otospongiosis (Schwartze sign).

• Acts by:

a. Decreases bone resorption

b. Increases bone formation

c. Prevents enzymatic damage to cochlea

• 20 mg orally, thrice daily for 3 - 6 months

Hearing Aid

For patients who:

• Are unfit for surgery

• Refuse surgery

Thank You