Cholesteatoma; Defination, type, etiology, management

1. CHOLESTEATOMA

2. Definition
• The term coined by Johannes Muller in 1838.
• defined as a cystic structure filled with desquamated
squamous debris lying on fibrous matrix.(skin in wrong
place)
Currently the Definition is,
 A three dimensional epidermoid structure
 Exhibiting independent growth
 Replacing the middle ear mucosa and resorption of the
underlying bone.

3. Histologically
• Cystic Content
o is composed of fully differentiated anucleate keratin squames.
• Matrix
o contains keratinizing squamous epithelium lining a cyst like
structure.
• Perimatrix
o known as lamina propria
o peripheral part of cholesteatoma consists of granulation tissue
and cholesterol granules.
o This layer is in contact with the bone. It is the granulation tissue
which releases enzymes that cause bone destruction.

4. Cholesteatoma

5. Classification
Can be classified as,
• Congenital cholesteatoma
• Acquired cholesteatoma.
o Primary acquired cholesteatoma
o Secondary acquired cholesteatoma

6. Primary acquired
• Etiology unknown
• there is no history of preexisting or previous episodes of
otitis media or perforation. Lesions just arise from the
attic region of the middle ear.
• Various theories have been proposed to explain the
pathophysiology

7. Pathophysiology
Cawthrone theory:
• suggested by Cawthrone in 1963
• that cholesteatoma always originated from
congenital embryonic cell rests present in
various areas of the temporal bone.

8. Pathophysiology
Tumarkin’s theory:
• cholesteatoma is derived by immigration of
squamous epithelium from the deep portion of
the external auditory canal into the middle ear
cleft through a marginal perforation or a total
perforation.

9. Pathophysiology
Toss theory of invagination:
• persistent negative pressure in the attic region
causes invagination of pars flaccida causing a
retraction pocket.
• This retraction pocket becomes later filled with
desquamated epithelial debris which forms a
nidus for the infection to occur later.
• Common organisms to infect this keratin debris
are Psuedomonas, E. coli, Proteus etc.

10. Retraction pockets
• A retraction pocket is an invagination of the
tympanic membrane. The negative middle ear
pressure, which is the cause of retraction pocket
• Toss classified attic retraction pockets into 4
grades:

11. • Grade I: The pars flaccida is not in contact with the neck
of the malleus.
• Grade II: The retracted pars flaccida is in contact with
the neck of the malleus and clothing it.
• Grade III: Here in addition to grade II features there is
minimal erosion of the outer attic wall
• Grade IV: In this grade in addition to all the above said
changes there is severe erosion of the outer attic wall
or scutum.

12. Pathophysiology
Metaplasia:
• This theory was first suggested by Wendt in
1873.
• The epithelium in the attic area of the middle
ear undergoes metaplastic changes in response
to subclinical infection.
• This metaplastic mucosa is squamous in nature
there by forming a nidus for cholesteatoma
formation in the attic region.

13. Pathophysiology
Habermann’s epithelial invasion theory:
• This theory suggests that following perforation of
the tympanic membrane, epithelium invades into
the attic area.

14. Secondary acquired
• This always follows active middle ear infection which
destroy the tympanic membrane along with the annulus.
• The destruction of annulus predisposes to epithelial
migration from the external auditory canal into the attic
region

15. Pathology
• Necrosis of tympanic membrane tissue along with its
annulus. caused due to the virulence of the organisms
involved i.e. beta-hemolytic streptococci.
• Necrosis starts to occur in those areas of ear drum
which have the poorest blood supply.

16. Congenital Cholesteatoma
• Are epidermoid tumors originating from the
embryonic epidermoid rest located in the
temporal bone or adjacent meningeal spaces.
• It appears as whitish globular masses lying
medial to an intact tympanic membrane.

19. Pathogenesis
Teed’s epithelial cell rest theory:
• Suggested by Teed in 1936
• the persistence of squamous epithelial cell rests
in the temporal bone lead to the formation of
congenital cholesteatoma.

20. Pathogenesis
Implantation theory:
• Friedberg suggested, viable squamous epithelial
cells in the amniotic fluid present in the middle
ears of neonates and hypothesized that this was
a possible source of congenital cholesteatoma

21. Pathogenesis
Ruedi's invagination theory:
• This theory suggests that in utero infection of
tympanic membrane causes invagination of ear
drum into the middle ear cavity causing
congenital cholesteatoma.

22. Post-traumatic cholesteatoma
a/c TertiaryAcquired
Mechanisms:
• Epithelial entrapment in fracture line
• In growth of epithelium through fracture line
• Traumatic implantation of epithelium into middle
ear

23. Causes of bone destruction
• Hyperaemic decalcification
• Osteoclastic bone resorption due to:
o Acid phosphatase
o Collagenase
o Acid proteases
o Proteolytic enzymes
o Leukotrienes
o Cytokines
• Pressure necrosis: No role
• Bacterial toxins: No role

24. Evaluation
• History
• Head and neck examination
• Otologic examination
• tuning fork examination-conductive hearing loss
• Hearing evaluation (PTA) -conductive hearing loss
• Tympanometry-Flat tympanograms
• CT scan of temporal bones

25. Complications
• Infection
• Otorrhea
• Bone destruction
o Ossicles, tegmen
• Hearing loss
• Facial nerve paresis or paralysis
• Labyrinthine fistula
• Intracranial complications

26. Management
• Aural toilet
• Antibiotics
• Grommet insertion (to manage early retraction pockets)
• Canal wall down mastoidectomy

27. Aural toilet
• Done only for active stage
– Dry mopping with cotton swab
– Suction clearance: best method
– Gentle irrigation (wet
mopping) Removes
accumulated debris
Acidic pH discourages bacterial growth