Cholesteatoma is a cyst-like structure in the middle ear filled with skin cells and debris. It can be congenital, arising from embryonic skin cell rests, or acquired through retraction of the eardrum or migration of skin cells through a perforated eardrum. The skin cells in the cholesteatoma produce enzymes that destroy the surrounding bone. Cholesteatoma is evaluated with examination, imaging, and hearing tests. Treatment involves surgery to remove the cholesteatoma and reconstruct the damaged bones.
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.
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.
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.
17.
18.
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 Tertiary Acquired
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
Notas do Editor
ant. epitympanum), petrous apex, cerebello-pontine angle
a portion of embryonic tissue that remains in the adult organism. Also called epithelial rest, fetal rest.
History
Hearing loss Otorrhea Evaluation Otalgia Nasal obstruction Tinnitus Vertigo Previous history of middle ear disease: CSOMTM perforation Previous surgery
The erosion of ossicles, most commonly in the incus, may result in conductive hearing loss
Tympanometry is a technique used to look at the function of the middle ear.
Middle ear pressure values ranging from +50 daPa to –200 daPa for children, and +50 daPa to –50 daPa for adults is generally considered normal.