The document discusses the middle ear transformer mechanism and ossiculoplasty surgery. It covers: 1) The middle ear transforms sound via 3 mechanisms - the catenary lever of the ear drum, ossicular lever ratio, and hydraulic lever area ratio. 2) Ossiculoplasty surgically repairs the ossicular chain to restore conduction. Materials used include autografts, allografts, and synthetic grafts. 3) Techniques depend on the ossicular status and include using prostheses, autografts, or reattaching existing ossicles. The goal is optimal sound transmission.

1. DR N JANARDHAN
PROF&HOD OF ENT
NMCH
NELLORE

2. MIDDLE EAR OSSICLES

3. Middle Ear
Transformer Mechanism BY 3 WAYS
1) CATENARY LEVER(ear
drum)
 Buckling mechanism of
TM
 Force is transmitted from
centre of TM.
 TM memb doesn’t move
as a plate.
 This causes high
pressure with low
displacement.

4. 2.OSSICULAR
LEVER(lever ratio):
 Length of the handle of
malleus 1.3 times longer
than long process of
incus.

5. 3.HYDRAULIC
LEVER(areal ratio):
 Average area of TM is
larger(60mmsq0 than
foot plate
area(3.2mmsq)(OW).
 Effective vibratory area of
TM 65% that is 45mmsq.

7. 7
Transformer in Diseased State
 Effect on Ossicular coupling
 Ossicular Discontinuity
 Ossicular Fixity
 Effect on Acoustic coupling
 Loss of Round Window shielding
 Effect of Stapes, Cochlear & RW Impedance
 Middle ear aeration / fluid

8. OSSCICULOPLASTY
 It is surgical repair of the ossicular chain to restore the
advantage of the conduction mechanism or middle ear
transformer mechanism in tympanoplasty
 The surgical repair includes to reconstruct the
diseased or dislocated or fixed osscicular chain .
 The material for this surgery may be with the availble
healthy osscicles or auto grafts or allogenic grafts or
synthetic material

9. Indications for Ossciculoplasty
 Discontinuity O.C
 Trauma
 Erosion by chronic otitis media/ cholesteatoma (most
common)
 Eroded incudostapedial joint (80% of patients)
 Eroded for absent incus
 Partially or fully eroded stapes
 Fixation
 Malleus head ankylosis (idiopathic)
 Ossicular tympanosclerosis
 Scar bands due to inflammaty middle ear disease

10. www.nayyarENT.com 10
Ossicular status
 Austin / Kartush Classification
Types Ossicular chain status
0 M+I+S+
A M+S+
B M+S-
C M-S+
D M-S-
E Ossicular head fixation
F Stapes fixation
Tuesday, July 17, 2012

11. WULLSTEIN CLASSIFICATION
 Type I with restoration of the normal
middle ear.
 Type II. Ossicular chain
partially destroyed . Skin graft laid against
the ossicles after removal of the bridge.
 Type III.Myringostapediopexy producing
a shallow middle ear and a columella
effect.
 Type IV. Round window protection
 Type V. Closed middle ear with round
window protection; fenestra in the
horizontal semicircular canal covered
by a skin graft

12. Nodol and Schuknecht modification
of the wullstein classification
 Type I – myringoplasty (intact and mobile ossicular chain)
 Type II – use of prosthesis to connect a discontinuity
between the long process of incus and stapes head.
 Type III – subdivided into three categories
 Type III stapes columella – placement of TM graft on to the
stapes head
 Type III minor columella – strut from stapes head to
manubrium/ TM.
 Type III major columella – strut from stapes foot plate to
manubrium / TM.

13. MATERIALS USED IN OSSICULAR
RECONSTRUCTION
BIOLOGIC MATERIALS:
1. Autograft or Homograft ossicles,
2.Cortical bone,
3. Teeth,
4.Cartilage.

14. Autografts
 Bone – ossicles, cortical bone( locally available , rigid,
easy shaping and sizing)
 Cartilage- unstable, loses rigidity, resorption
 Advantages:
 Low extrusion rate
 No risk of transmitting disease
 Low cost
 No necessity for reconstitution
 Fully biocompatible

15.  Disadvantages
1. Prolonged operative time to obtain and shape
2.Resorption
3. Fixation.
4.Recurrence of the disease

16. HOMOGRAFTS/ALLOGRAFTS
 Ossicles / cartilage/dura
From either living or cadavers of from other s,
after denaturing the biological active acomponents of
the material

17. Methods of homograft
preservation
 70% ethyl alcohol
 0.02% Aqueous Cialit, (Sodium 2-
ethylmercurithiobenzoxazole-carboxylate)
 4% Buffered formaldehyde fixation and 0.5%
buffered formaldehyde preservation.

18. Advantages:
Easily availability, low cost and good biocmpatibility
Disadvantages
 Must be stored in special conditions
 Risk of transmitting diseases (eg, AIDS,
Creutzfeldt-Jakob disease, Mad cow disease or
Bovine spongeform encephalopathy)

19. Synthetic material grafts
METALS
: titanium, gold and
stainless
steel,platinum,silver
NONMETALLIC
Polymers:
Solids-Teflon(polytetrafluroethylene
Porous-Plastipore
:Ceramics:
Bioinert- frialit
Bioreactive – ceravital/bioglass
Biodegradable- Hydroxyl apatite

20.  Advantages:
 Readily available
 Presculptured
 Free from infectiious diseases
 Disadvantages:
 More expensive
 Higher extrusion rate (controversial)
 Migration

21. Applebaum I S prosthesis
Titanium I S prosthesis
(KURZ angular)

24. IDEAL PROSTHESIS
 Biocompatible,
 Stable,
 Safe,
 Easily insertable, and
 Capable of yielding optimal sound transmission

25. GLUES AND ADHESIVES
Tissue glues
 Mecrylate(COAPT-1)
 Bucrylate(COAPT)
 Eubucrylate(Histo-Acryl)
Fibrin glues
 Tissucol/Tisseel ( human fibrinogen & factor XIII
with thrombin ca cl2/aprontinin sol.)

26. CONTRAINDICATIONS
 Acute infection of the ear is the only true
contraindication. ( poor healing, prosthesis extrusion)
 Relative contraindications :
1. persistent middle ear mucosal disease.
2. tympanic membrane perforation.
3. repeated unsuccessful use of the same or similar
prostheses.

27. Types of ossciculoplasty
 Primary : ossiculoplasty and mastoidectomy done
simultaneously
 Secondary: Staging ossiculoplasty: first eradication of
the disease by mastoidectmy and ossciculoplasty after
6 m0nths or one year

28. REQUIREMENTS OF PRIMARY
OSSICULOPLASTY
 Presence of normal or minimal hypertrophied ME
mucosa
 Diseased ME mucosa over the promontory is
removed but normal or hypertrophied mucosa at
the ET orifice or hypotympanic area
 Patent ET orifice
 Mobile Stapes FP

29. TECHNIQUES OF OSSICULOPLASTY
 In this situation, a
standard PORP can be
used
Mobile stapes and mobile malleus, but absent incus
Dornhoffer interpositional PORP

30.  Incus sculptured and
used

31. PENNINGTON

32. Cont…
Double dowel technique

33. WEHRS

35. Mobile stapes and fixed malleus, but absent
incus:
 the head of the malleus can be amputated
 PORP can be used to connect the handle of the
malleus/tympanic membrane with the stapes.

36. Incus necrosis and mobile stapes
and malleus
bone cement in ossicular reconstruction have shown good
hearing results (air-bone gap ≤20 dB) in 90% of patients.

37.  When a significant amount of incus necrosis is found,
a titanium incus/bridge prosthesis can be used
Kurz angular prosthesis (Plester)

38. Fixed footplate and mobile malleus
and incus
 A standard stapedectomy or stapedotomy is
performed.

39. Absent stapes superstructure, but mobile
footplate, incus,
and malleus
a stapes prosthesis can be
crimped to the incus and placed
on the footplate.

40. Foreshortened incus and a fixed
footplate or prior stapedectomy
1.the incus discarded, the
footplate removed or
fenestrated,and TORP
placed.
 2. Winkle prosthesis that
attaches to the
foreshortened incus and
extends into a small
fenestra in the footplate.

41. Fixed stapes and fixed or mobile
malleus, but absent incus:
 An incus replacement
prosthesis wrapped
around the manubrium
of the malleus, and the
malleus head
amputated.
 More recently, a titanium
prosthesis with a ball
joint has been developed

42. Total fixation of the ossicular chain
 incus is discarded, a
fenestra created in the
footplate, and
 the head of the malleus
amputated after the
prosthesis has been
clipped to the
manubrium

43. TORP
 Total ossicular
replacement prosthesis,
positioned on the stapes
footplate covered with
pressed tragal
perichondrium, when
the malleus is not
present

44.  Total ossicular
replacement prosthesis
with incised oversewn
cartilage, notched to fit
under the malleus
handle to prevent
migration

45.  Total ossicular
replacement prosthesis
positioned over an open
vestibule covered by
pressed perichondrium

46. Double Cartilage Block
 Obtaining tragal
cartilage for double
cartilage block ossicular
reconstruction.

47.  Composite of cartilage
preparation incising
cartilage to, but not
through, the attached
perichondrium and final
placement of the double
cartilage block with
attached perichondrium
onto stapes, slightly
elevating the tympanic
membrane (grafted or
not

48.  Composite of
preparation to obtain
additional height and
placement using a triple
cartilage block.

49. Cartilage Preparation
 routinely used to interface between the prosthesis and
the overlying tympanic membrane
 The prosthesis is tilted posteroinferiorly, the cartilage
is placed over the anterior edge of the platform, and
both are gently rocked back into position, maintaining
slight tension on the tympanic membrane.

50. Cartilage shoe in oval window niche with
prosthesis
in position on mobile footplate

51. Placement of Prosthesis
 the prosthesis be under slight tension and at a
favourable angle.
 The prosthesis should fit perfectly without tension
before placement of the cartilage.
 Before placing the prosthesis, the middle ear is
partially filled with a middle ear packing material.
 Bone cement cannot be used on the footplate,
however. Instead, a cartilage punch (Kurz) is used to
create a “cartilage shoe.

52. POSTOPERATIVE CARE
 This dressing is removed on the patient’s first
postoperative day.
 The patient is instructed to keep the ear dry.
 Four weeks postoperatively, the patient is instructed
to instill antibiotic ear drops

53. Complications
 Tear of the annular ligament with a perilymphatic
fistula.
 Severe or total sensorineural hearing loss.
(great care and precision.)

54. The functional results of ossiculoplasty are improved
by
1. Atticotomy
2. Middle ear and Eustachian tube sheeting
3. Reconstruction of posterosuperior canal wall
and reinforcement of posterosuperior
tympanic membrane
4. Transmastoid drainage
5. Staging

55. MY TECHNIQUES

57. References
 Text book of Otolaryngology – Head & Neck Surgery :
Charles W Cummings, 4th ed , vol 4, 3058 – 74
 Manual of Middle Ear Surgery : Mirko Tos, vol 1
 The Otolaryngologic Clinics of North America : Aug 1994;
Ossiculoplasty, vol 27, No 4
 Surgery of the Ear : Glasscock – Shambough, 5th ed
 Scott Brown otolaryngology 7th edition
 Internet Journal articles

58. THANK YOU