DR. MUDASIR (ENT)

Otosclerosis : 

Otosclerosis Dr. Mudasir - ul -Islam

Definition: 

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: 

Antonio Valsalva First described Ankylosis of Stapes in 1741

Adam Politzer: 

Adam Politzer Coined the term Otosclerosis in 1893

Friedrich Siebenmann: 

Friedrich Siebenmann Coined the term Otospongiosis in 1912

History of Otosclerosis: 

History of Otosclerosis 1704 – Valsalva first described stapes fixation 1857 – Toynbee linked stapes fixation to hearing loss 1890 – Katz was first to find microscopic evidence of otosclerosis 1893 – Politzer described the clinical entity of “otosclerosis”

Epidemiology: 

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)

Pathology: 

Pathology Two phases of disease Active ( otospongiosis phase) Osteocytes , histiocytes , osteoblasts Active resorption of bone Dilation of vessels Schwartze’s sign Mature (sclerotic phase) Deposition of new bone (sclerotic and less dense than normal bone)

“Blue mantles of Manasseh”: 

“Blue mantles of Manasseh”

Pathophysiology: 

Pathophysiology

Pathology: 

Pathology Most common sites of involvement Fissula ante fenestrum Round window niche (30%-50% of cases) Anterior wall of the IAC

Types of Otosclerosis: 

Types of Otosclerosis A. Stapedial B. Cochlear: otosclerotic focus is seen over   Round window  P romontory C. Stapedial + cochlear: mixed type D. Malignant: rapidly progressing cochlear lesion with severe sensori -neural deafness.

Types of Stapedial Otosclerosis: 

Types of Stapedial Otosclerosis 1. 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: 

Types of Stapedial Otosclerosis 4. Biscuit type: footplate involved, margin is free. 5. Obliterative: obliterates oval window completely.

Non-clinical foci of otosclerosis: 

Non-clinical foci of otosclerosis

Bipolar involvement of the footplate: 

Bipolar involvement of the footplate

Hyalinization of the spiral ligament: 

Hyalinization of the spiral ligament

Organ of Corti: 

Organ of Corti

Symptoms of Otosclerosis: 

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 Otosclerosis: 

Symptoms of Otosclerosis 4. Paracusis Willisii : Pt has better hearing in noisy surroundings (people increase their voice intensity & pt’s speech discrimination becomes better).

Otoscopy: 

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 Tests: 

Tuning Fork Tests Rinne Weber A.B.C. Stapedial Negative (BC > AC) Lateralizes to Deaf ear Normal Cochlear Positive (AC > BC) Lateralizes to Better ear Decreased Mixed Negative (BC > AC) Lateralizes to Better ear Decreased

Gelle & Bing Tests: 

Gelle & Bing Tests Vibrating 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: 

Pure Tone Audiometry Low frequency conductive deafness Carhart’s notch in bone conduction at 2 KHz

Pure Tone Audiometry: 

Pure Tone Audiometry Carhart’s notch Hallmark audiologic sign of otosclerosis 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

Pure Tone Audiometry: 

Pure Tone Audiometry Carhart’s notch Proposed theory Stapes fixation disrupts the normal ossicular resonance (2000 Hz) Normal compressional mode of bone conduction is disturbed because of relative perilymph immobility Mechanical artifact Reverses with stapes mobilization

Speech Audiometry: 

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: 

Speech Audiometry

Impedance Audiometry: 

Impedance Audiometry A s curve seen in 40 % cases of otosclerosis . Normal middle ear pressure + decreased middle ear compliance . Others have A curve.

Stapedial reflex present: 

Stapedial reflex present

Stapedial reflex absent: 

Stapedial reflex absent

C.T. Scan Temporal Bone: 

C.T. Scan Temporal Bone 20 0 coronal oblique cuts are taken

Imaging: 

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

Imaging: 

Imaging CT Axial cuts Patient position – canthomeatal line perpendicular to the table top 1 mm cuts Top of sup. SCC to bottom of the cochlea Coronal Patient position – supine w/ head overextended face turned 20 degrees ipsilateral

Stapedial Otosclerosis (Coronal): 

Stapedial Otosclerosis (Coronal)

Cochlear Otospongiosis (Axial) : 

Cochlear Otospongiosis (Axial)

Differential Diagnosis: 

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

Management: 

Management Medical – Sodium Fluoride Amplification Surgery Combinations

Patient Selection: 

Patient Selection Factors Result of TF tests and audiometry Skill of the surgeon Facilities Medical condition of the patient Patient wishes

Patient Counseling: 

Patient Counseling Options for treatment Advantages and disadvantages of each Repeat clinic visit

Medical: 

Medical Sodium Fluoride 1923 - Escot suggested using calcium fluoride 1965 – Shambaugh popularized its use Mechanism Fluoride ion replaces hydroxyl group in bone forming fluorapatite resistant to resorption Increases calcification of new bone Causes maturation of active foci of otosclerosis

Slide 44: 

Sodium Fluoride Reduces tinnitus, reverses Schwartze’s sign, resolution of otospongiosis seen on CT OTC – Florical Dose – 20-120mg Indications Non-surgical candidates Patients who do not want surgery Surgical candidates with + Schwartze’s sign Treat for 6 mo pre-op Postop if otospongiosis detected intra-op

Slide 45: 

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

Amplification: 

Amplification Amplification Excellent alternative Non-surgical candidates Patients who do not desire surgery Satisfaction rate less than with successful Sx Canal occlusion effect Amplification not used at night

Slide 47: 

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)

History of Otosclerosis and Stapes Surgery: 

History of Otosclerosis and Stapes Surgery John Shea 1956 – first to perform stapedectomy Oval window vein graft Nylon prosthesis from incus to oval window

Surgery: 

Surgery Best surgical candidate Previously un-operated ear Good health Unacceptable ABG 25 to 40 dB, bilateral ABG recommended by different authorities Negative Rinne test Excellent discrimination Desire for surgery

Surgery: 

Surgery Other factors Age of the patient Elderly Poorer results in the high frequencies Congenital stapes fixation (44% success rate) Juvenile otosclerosis (82% success rate) Occupation Diver Pilot Airline steward/stewardess

Surgery: 

Surgery Other factors Vestibular symptoms Meniere's disease Concomitant otologic disease Cholesteatoma Tympanic membrane perforation

Surgical Steps: 

Surgical Steps Subtleties of technique and style Local vs . general anesthesia Stapedectomy vs. partial stapedectomy vs. stapedotomy Laser vs. drill vs. cold instrumentation Oval window seals Prosthesis

Slide 53: 

Pre-op Confirm the correct ear (largest ABG) With the patient Audiogram History and physical exam Place CT and audiogram in a visible location in the OR for easy intra-operative evaluation

Canal Injection: 

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

Raise Tympanomeatal Flap: 

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

Separation of chorda tympani nerve from malleus: 

Separation of chorda tympani nerve from malleus Separate the chorda from the medial surface of the malleus to gain slack Avoid stretching the n. Cut the nerve rather than stretch it

Curettage of Scutum: 

Curettage of Scutum Curettage a trough lateral to the scutum, thinning it Then remove the scutum (incus to the round window) Visualize the pyramidal process and facial n.

Curettage of Scutum: 

Curettage of Scutum Exposure of pyramidal process and facial n. Preservation of bone over incus

Middle ear examination: 

Middle ear examination Mobility of ossicles Confirm stapes fixation Evaluate for malleus or incus fixation Abnormal anatomy Dehiscent facial nerve Overhanging facial nerve Deep narrow oval window niche

Measurement for prosthesis: 

Measurement for prosthesis Measurement Lateral aspect of the long process of the incus to the footplate Average 4.5 mm

Total Stapedectomy: 

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

Stapedotomy/Small Fenestra: 

Stapedotomy/Small Fenestra Originally for obliterated or solid footplates Europe 1970-80 First laser stapedotomy performed by Perkins in 1978 Advantages Less trauma to the vestibule Less incidence of prosthesis migration Less fixation of prosthesis by scar tissue

Drill Fenestration: 

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

Laser Fenestration: 

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

Fenestration: 

Fenestration Causse et al. (1993) Recommends posteriorly placed fenestration to better recreate the natural physiologic dynamics of the footplate

Posterior Fenestration: 

Posterior Fenestration Posteriorly placed fenestration with the laser Causse also recommends following the laser with the diamond burr to remove char

Oval window seal: 

Oval window seal Tragal perichondrium Vein (hand or wrist) Temporalis fascia Blood Fat

Vein graft : 

Vein graft

Reconstructing the annular ligament: 

Reconstructing the annular ligament

Placement of the Prosthesis: 

Placement of the Prosthesis Prosthesis is chosen and length picked Some prefer bucket handle to incorporate the lenticular process of the incus

Stapedectomy vs. Stapedotomy: 

Stapedectomy vs. Stapedotomy ABG closure < 10dB (PTA)

Stapedectomy vs. Stapedotomy: 

Stapedectomy vs. Stapedotomy ABG closure at 4 kHz

Special Considerations and Complications in Stapes Surgery: 

Special Considerations and Complications in Stapes Surgery

Overhanging Facial Nerve: 

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

Floating Footplate: 

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

Floating Footplate: 

Floating Footplate Hearing results Thin or blue footplate – 97% ABG closure (<10dB) White or “biscuit” footplate – 52% ABG closure

Diffuse Obliterative Otosclerosis: 

Diffuse Obliterative Otosclerosis Occurs when the footplate, annular ligament, and oval window niche are involved Bone is thinned with a small cutting burr Blue lined at anteroposterior edges first

Perilymphatic Gusher: 

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

Round Window Closure: 

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

SNHL: 

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

Reparative Granuloma: 

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 posterior TM Treatment ME exploration Removal of granuloma Prognosis – return of hearing with early excision

Vertigo: 

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

Recurrent Conductive Hearing Loss: 

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