middle ear reconstruction
TRANSCRIPT
Dr. Muhammad Mozammal Haqure
Historical Background
Berthold (1878):
Myringoplastik
Full thickness skin graft
Nylen (1921): Monocular operating
microscope.
Holmgren, teacher of Nylen (1922):
Binocular operating microscope
In 1953, the Zeiss operating microscope:
Commercially available
Historical Background…..
Moritz (1952)
Zollner (1953, 1955) German,
Wullstein (1953,1956) Onlay skin graft
To restore or conserve hearing and promote healing, after excision of disease from the middle ear and mastoid.
Middle Ear Reconstruction
Not only the restoration of the anatomical ormechanical components but also of thephysiology or function of the ear.
Tympanoplasty
Ossiculoplasty
Mastoidectomy:
Open or canal wall-down procedures
Closed or canal wall-up procedures
Tympanoplasty
Definition: Repair of the tympanic membrane
(TM) with inspection of middle ear & possible
ossicular chain reconstruction.
This is different than a myringoplasty
Aims:
Prevent recurrent disease
Improve hearing
Provide a dry ear canal
Enable patient to bathe & swim freely
Tympanoplasty………..
Appropriate candidates: Perforation of TM
Cholesteatoma / other lesion involving TM or tympanic cavity
Resolved otorrhea
Preferably no Eustachian tube dysfunction
Tympanoplasty………..Poor Candidates:
Multiple failed attempts at closure
Poor Eustachian tube function
Smoker
Systemic disease
DM
Steroid use
Actively draining
Tympanoplasty……….. Commonly used materials:
Temporalis fascia
Perichondrium/cartilage
Periosteum
Fat
Vein
Duramater
Techniques Overlay
Underlay
Tympanoplasty………..
Approaches
Transcanal
Post auricular
Endaural
Tympanoplasty………..
Wullstein (1956)
Type I
Type II
Type III
Type IV
Type V
Types of tympanoplasty
Type I—
intact ossicular chain
simple
tympanoplasty
(Myringoplasty)
Types of tympanoplastyType II—
intact incus and
stapes with erosion
of malleus
Graft onto incus
= incudopexy
Graft onto malleus
remnant
Types of tympanoplastyType III—
intact mobile stapes
superstructure
Graft onto head of
stapes
Columella
tympanoplasty
Types of tympanoplastyType IV—
intact stapes footplate
with absent or
eroded stapes
superstructure
Footplate MOBILE
Graft covers RW
(round window baffle)
Footplate exteriorized
Types of tympanoplasty
Type V- fenestration of horizontalsemicircular canal
Immobilefootplate
Underlay v. Overlay
Underlay= medial Overlay= lateral
Underlay technique—selection of patients Posterior central perforations
“Smaller” perforations
Any perforation with intact annulus
Underlay technique—procedure
Overlay technique—selection of patients
Marginal perforations
Total perforations/“larger perforations”
Need for canalplasty
Previously failed tympanoplasties
Overlay technique—procedure
Tympanoplasty--complications Persistent / recurrent perforation
Cholesteatoma (ME, drum, EAC)
Dysguesia
Blunting
Lateralization
SNHL / vertigo
Facial nerve injury
Ossicular disorders Types
Ossiculardiscontinuity
Ossicular fixation
Causes Chronic otitis media
Trauma
Congenital
Tympanosclerosis
Otosclerosis
Common ossicular disorders
Long process of Incus
Stapes superstructure
Handle of the Malleus
Ossiculoplasty (OCR)
Appropriate candidates:
Resolved otorrhea with no middle ear disease
Conductive or mixed hearing loss
No Eustachian tube dysfunction (ideal)
Need enough middle ear space and aeration to allow for prosthesis and function
Previous CWU for second-look
Ossicular grafts and implants
Autologous :
Ossicle grafts: Incus/ Head of the malleus
Cortical bone grafts: Mastoid cortex
Cartilage
Homologous human ossicles
Synthetic ossicular implants:
Porous high-density polyethylene (Plastipore) -FBGCR
Plastic material -microdegradation
Bioactive glasses, aluminum oxide ceramic, carbon,
hydroxylapatite-polyethylene (Hapex)
Ossicular chain defect Austin’s classification
4 Common types: Incus absent in all cases and TM reconstruction
required in all cases.
Type A: M+, S+
Loss of part of incus or total loss of incus.
Type B: M+, S-
Loss of incus & stapes superstructure but the malleus handle still
present.
Type C: M-, S+
Loss of incus & malleus but the stapes superstructure still present.
Type D: M-, S-
Loss of incus, malleus & superstructure of stapes, but mobile
footplate still present.
Type A1: Bone pate-glue/ prosthesis
Type A2: Autograft or homograft bone (Incus
interposition) / Prosthesis
Type B: Autograft or homograft bone/ Prosthesis
Type C: PORP/ Autograft or homograft bone
Partial Ossicular Replacement Prosthesis Intact superstructure
Stapes superstructure TM
PORP - Types
Type D: TORP/ Autograft or homograft bone
Total OssicularReconstruction Prosthesis
Footplate TM
Oval window (with graft)TM
TORP
All OCRs are held in place by tension. When placing a TORP, Gantz will frequently put a second
piece of cartilage to support the prosthesis.
Ossicular chain defect…….
Rare ossicular chain defects
1)Isolated loss of the malleus handle: 2%
2) Isolated loss of the stapes superstructure: 1.7%
Continue….Fixed stapes
1) Malleus handle presnt stapes fixed
2) Malleus handle absent stapes fixed
Defining Success 1995 guidelines of the AAO
Pre and postoperative air-conduction and bone-
conduction thresholds are measured at 4 designated
frequencies (0.5, 1, 2, and 3 kHz), then averaged
Success is defined as a mean postoperative air-
bone gap of less than 20 dB and is the main
outcome considered for this talk
Prognostic Factors It is clear that optimal results depend not only on
the qualities of the prosthesis, but also on the
environment in which it is placed and the
surgical techniques used.
Prognostic Factors Austin (1972) defined four groups in which the incus
had been partially or completely eroded:
Type A, malleus handle present, stapes
superstructure present (60% occurrence)
Type B, malleus handle present, stapes
superstructure absent (23%)
Type C, malleus handle absent, stapes
superstructure present (8%)
Type D, malleus handle absent, stapes
superstructure absent (8%)
Prognostic Factors Kartush (1994) proposed a scoring system called
the middle ear risk index (MERI) to form an index score to determine the probability of success in hearing restoration surgery.
MERI is used to describe the preoperative middle ear environment at the time of ossiculoplasty
Prognostic Factors
All studies of prognostic factors identify middle ear
mucosal status and presence of malleus handle
as important predictors of successful hearing
restoration
Result of ossicular reconstruction Incus/stapes assembly - air-bone gap closure with 10 dB
in 50% cases & under 20 dB in 70-80% cases.
Malleus/stapes assembly –
0-10 dB 50% cases
0-20 dB in 80% cases
Malleus/footplate assembly-
20 dB in 35- 60% cases.
Use of PORP – air-bone gap closure < 20 dB in 77% cases.
Use of TORP – air-bone gap closure < 20dB in 52% cases.
expert surgeon
Complications Persistent CHL
Recurrent CHL
• Displaced ORP
• Extruded ORP
SNHL
Vertigo
Facial nerve injury
Mastoid surgery
Canal wall down/open cavity mastoidectomy
Canal wall up/intact canal wall/closed cavity
mastoidectomy:
Mastoid Surgery…….
Aims:1) Eradication of disease
2) An epithelialized, self cleaning ear.
3) Hearing improvement.
Canal wall down/open cavity mastoidectomy
A. Obliteration techniques
B. Posterior canal wall and outer attic wall
reconstruction.
A. Obliteration techniquesTo line & reduce the size of the mastoid cavity
or
Obliterate it completely
Obliteration techniques…………..
Autologous cancellous iliac crest bone graft (Schiller & Singer, 1960)
Allogenic femoral cortical bone chips
(Shea, Gardner and Simpson, 1972)
Bone chips/ dust
Autogenous cartilage (chondral part of pinna)
Hydroxylapatite ceramic powders &
particles.
Obliteration techniques………….. The muscle obliteration techniques:
(more popular)
Local random pattern muscle periosteal transposition & rotation flaps of sternomastoid muscle( Meurmanand Ojala, 1949)
Temporalis muscle (Rambo, 1958)
Postauricular muscle periosteal flaps based on the SCM muscle (Hilger and Hohmann, 1963)
Anteriorly based postauricular muscle-periostealtransposition flaps together with bone pate (Palva, 1963,1982,1993)
Obliteration techniques…………..Local axial pattern flaps:
Temporoparietal fascia flap, based on the
superficial temporal vessels (Byrd, 1980; East,
Brough and Grant, 1991)
The temporalis fascia flap; ‘Hong Kong flap’ ,
(van Hasselt, 1994)
Free grafts: Fascia (temporalis), fascia lata,
abdominal fat, local muscle and periosteal grafts
B: Posterior canal wall and outer attic
reconstruction-
Alternative to cavity obliteration.
Autologous material
> Bone dust & chips
> Cortical bone graft
> Tragal cartilage/Scaphod cartilage
Allogenic
> Bone graft
> Tragal cartilage
Hydroxylapatite
Tympanoplasty with mastoidectomy1) Closed cavity mastoidectomy with tympanoplasty.
2) Open cavity mastoidectomy with tympanoplasty.
3) Obliteration of open mastoid cavity with tympanoplasty.
4) Reconsturction of the outer atlic wall or posterior canal wall of open mastoid cavity with tympanoplasty.
Ossicular chain reconstruction 1) When incus is eroded but malleus handle & stapes
is present.
Malleus/stapes assembly by –
> Autologous & allogenic malleus head or incus body
to fit between the malleus handle & stapes head.
> Artifical prostheses are also available to perform
the same task.
Continue…2) When loss of incus & stapes superstructure but
handle of the malleus present.
Malleus/footplate assembly by-
> Autologous or homologous bone can be used.
> Artifical prostheses are also available.
3) When loss of incus & malleus but stapes
superstructure present.
TM/ stapes head assembly by-
> Autograft or homograft bone can be used .
> Artfical prostheses are also available.
Continue….
4) When loss of incus, malleus & stpaes
superstructure
but mobile footplate.
TM/ footplate assembly by-
> Autograft or homograft bone can be used.
> Artifical prostheses are also available.
SURGICAL APPROACHES
A. Post Aural (William Wilde) Incision: A cured incision is wade in the natural Post aural
gulcus. Starting nt the 12 o’ clock Position sumperorly and terminatiog at the 6 o’clock
position just behing the ear lobule
Used
Myringoplasty & Tympano Pasty ( Comsined At)
Masteidectomy (All)
Cochler Implant
Exposove of CN VII in vertical sac.
B. End aural inusion: i) incision in the canal and icisuratermials
Lempert I: It is semicircular incision made from 12 ‘o clock to 6 o’ clock Position in the
posteromeatul wall at the bony Cartilaginous function.
Lempert II: Starts from the 1st incision at 12 o clock and them pome upwords in a cuvilinear
fashion btween tragus and crus of helix. It pases though the incisura terminals and them
doen not cut hte cartilage. Both masterd and external canal surgery can be done
Indication:
Lage tympanic membrane perforations.
Attic cholesleatonas with limited extension into the andrum.
Excesion of osteona or exostosis of earcanal.
Modified radical mastordectomy where disane is limited to attic, antrum and part of
masted.
C. Permeatal approacho ( tramcanal) (Endomeatal)/
Rosen incision ( Lateral Tympanotomy)
Resn’s incisim in the most commonly used for stapectechomy It comnts of two parts
a) A Small vertical inlision at 12’ o Clock Position near the annulus and
Acarvilinear incirion storting at 6 o’ clock Position to meet the 1st incision in the poster superior region of the canals, 5mm-7mm away from the annulus.
Indication:
Stepes surgery
Myrugplasty
Omicnler chain reconstruction
Exporatory tumpanotomy Examination of omcular chain in congenital conductive defames.
Success rate in achieving tympanoplasty?
Ans: In expert hand armed -95%
Trainee – 74%
Most out patiant methods have a success rate of between 30 and 80 percent depending on pathology technique and operator Patience Minor surgery for small defects can be successful in 80% or More Myringoplasty can be expected to close 90% of Perforndim with a follow up of 12 months in experiorud hands.