1) Otosclerosis is a disease of the bony labyrinth where normal bone is replaced by spongy vascular bone. It most commonly causes conductive hearing loss. 2) Stapedial otosclerosis is the most common type and results in a lesion in front of the oval window causing progressive conductive hearing loss. 3) Treatment options include hearing aids for mild cases and stapes surgery to replace the stapes footplate for more severe conductive hearing loss. Complications of stapes surgery include sensorineural hearing loss or perilymph fistula.

1. OTOSCEROSIS
DR ARJUN ANTONY GRAISON
MSENT, DNB, DOHNS
ELHT, UK

2. More aptly called as Otospongiosis
• Disease of the Otic capsule/ Bony labyrinth, where normal
enchondral bone is replaced by spongy vascular bone formation.
•Autosomal Dominant with Incomplete penetrance

3. Etiology, Incidence , Prevalence
•Unknown
•Prevalence- 0.3% of the population – clinical disease
•More in Caucasians
•Age – 15 to 40 years , more common 20-30yrs
•Male: Female = 1:2
•Hormonal – progress rapidly during pregnancy, puberty & menopause.
•Known Associated with Osteogenesis Imperfecta
•Triad- Osteogenesis Imperfecta, otoscerosis, blue sclera – Van der Hoeve
Syndrome

4. Pathogenesis
3 theories
• Expression of a genetic mutation in collagen metabolism- in otic capsule
maturation.
• Expression of humoral autoimmunity to type II collagen.
• Expression of persistent measles virus infection of otic capsule-derived bone.

5. Types
•Stapedial otosclerosis
•Cochlear otosclerosis
•Histological otosclerosis

6. Stapedial Otosclerosis
Lesion – infront of Oval window – “fissula ante fenestrum”- most common site

7. Clinical Features
•SYMPTOMS
•STAPEDIAL type - Conductive
hearing loss- progressive, insidious,
often bilateral
•Paracusis Willisii
•Tinnitus- more common in active
lesions & cochlear type
•Vertigo – uncommon
•Speech – monotonous well
modulated soft speech
COCHLEAR type- High frequency hearing loss

8. SIGNS
SCHWARTZE SIGN- reddish hue on promontory- active focus with increased vascularity- 10%

10. STAPEDIAL OTOSCLEROSIS- PTA

11. Carhart’s Effect- Proposed theories
•Stapes fixation disrupts the normal ossicular resonance (2000 Hz)
•Loss of Ossicular inertia

12. Cochlear Otosclerosis - PTA
COOKIE BITE PATTERN

13. Acoustic reflexes
•Earliest evidence of otosclerosis
•Diphasic pattern – only one end of footplate is fixed
•Increase in compliance at onset and termination of stimuli (probe in affected ear).
•Footplate completely fixed- reflex absent.

14. CT

16. STAPEDIAL OTOSCLEROSIS

17. NaF – level 4
level
Of evidence
HEARING AID

18. Selection criteria for stapes surgery
•- CHL 30db or more
•Minimum Air bone gap – 15db with Rinne’s negative for 256hz &
512hz
•Speech Discrimination score – 60% or more.

19. Contraindications – Stapes surgery
•Only hearing Ear
•Associated Meniere’s Disease
•Young children- recurrent ET dysfunction common
•Professional athletes, Divers, high construction workers, frequent air travellers-
If the patient has an occupational requirement for intact vestibular function.
•Work in Noisy environments- more prone to noise trauma
•Avoided during pregnancy
•Relative contraindications- otitis externa, TM perforation.

21. COMPLICATIONS
Most dreaded complication –sudden SNHL/ DEAD EAR- rupture of reissner’s
membrane- drastic drop of cochlear action potential.

23. Etiology- dead ear
1. SEROUS LABYRINTHITIS- 5 types of inner ear reaction to traumatic stapes surgery
2. Acoustic trauma
3. Excessive foot plate mov/ trauma from prosthesis
4. Inadvertent rupture of inner ear membrane
5. Rapid loss of perilymph
6. HYDROPS- (excessive buildup of endolymph)
7. HYPOTONIC ATROPHY- shrinking of all structures of cochlear duct
8. SUPPURATIVE LABYRINTHITIS

24. Other Complications
•PERILYMPH FISTULA – Immediate & Delayed
•PostOP REPARATIVE GRANULOMA
•If poor hearing post op – Tinnitus worse
•INTRA OP COMPLICATIONS
•- STAPES GUSHER
•PERILYMPH FLOODING/ GUSHER

25. Gusher syndrome
X-linked congenital mixed deafness, the IAC is abnormally wide.
This creates a communication between the high-pressure cerebrospinal fluid in the IAC and the
perilymph of the Inner ear,leading to a leakage,
the “stapes gusher,”during stapes surgery.
The pathological widening concerns also the Fallopian canal.
The enlarged IAC may be seen on CT scan,with a globulous aspect, but this aspect Is not specific.
The widened angle between the first and the second segment of the facial nerve is highly
suggestive of the Gusher’s syndrome,enabling the preoperative diagnosis of this pathology

27. Enlarged vestibular aqueduct

28. INTRA OP COMPLICATIONS
•FLOATING/ SUBMERGED FOOTPLATE OF STAPES
•PERSISTENT STAPEDIAL ARTERY, OVERHANGING FACIAL NERVE
•INCUS LONG PROCESS NECROSIS
•CONGENITALLY FIXED MALLEUS
•Diffuse obliterative otosclerosis
•Round window otosclerosis/ closure

29. WHEN TO TAKE BACK TO THEATRE/
REVISION STAPES SURGERY
1. Immediate POST OP PERSISTENT VERTIGO- excessive stimulation by prosthesis.
NOT URGENT FACTORS
1. Delayed or immediate post op CHL of atleast 20db in speech frequency

30. References
1. Toscano ML, Shermetaro C. Stapedectomy. [Updated 2021 Jan 12]. In: StatPearls [Internet].
Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from:
https://www.ncbi.nlm.nih.gov/books/NBK562205/
2. Lee TC, Aviv RI, Chen JM, Nedzelski JM, Fox AJ, Symons SP. CT grading of otosclerosis.
American Journal of Neuroradiology. 2009 Aug 1;30(7):1435-9.
3. Kishimoto M, Ueda H, Uchida Y, Sone M. Factors affecting post operative outcome in
otosclerosis patients: predictive role of audiological and clinical features. Auris Nasus Larynx.
2015; 42(5):369–373
4. Shea JJ Jr. A personal history of stapedectomy. Am J Otol. 1998; 19(5, Suppl):S2–S12
5. Virk JS, Singh A, Lingam RK. The role of imaging in the diagnosis and management of
otosclerosis. Otol Neurotol. 2013; 34(7):e55–e60

31. THANK YOU