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Atelectasis & adhesive
• Kayvan Aghazadeh M.D
• Assistant prof. of otolaryngology
• Tehran university of medical siences
• Amir Alam hospital
• Middle ear atelectasis is thought to result mainly
from long-standing eustachian tube dysfunction.
• One of the main functions of the eustachian tube is
ventilation of the middle ear and mastoid
• Opening of the eustachian tube allows exchanging
of gases and equalization between the
environment and middle ear.
• The middle ear gases also are exchanged with the
middle ear mucosa.
• Bilateral diffusion between the middle ear cavity
and the blood may be an important factor in
middle ear atelectasis because:
the gas composition of the middle ear basically
resembles that of venous blood.
• If the atelectasis develops, the tympanic
membrane becomes retracted onto the
promontory and the ossicles of the middle ear.
• In atelectatic ears, the middle ear space is partially
or completely obliterated, but the tympanic
membrane is not adherent to the medial wall of the
middle ear,
and the mucosal lining of the middle ear is intact
• In contrast, adhesive otitis media exists when the
middle ear space is totally obliterated,
• and the tympanic membrane is adherent to the
ossicles and promontory;
mucosal surfaces are not present.
• Retraction of the tympanic membrane may lead to
erosion of the long process of the incus and the
stapes suprastructure
• Not all patients with chronic OME develop
atelectasis; in most patients with OME, retraction of
the tympanic membrane is limited.
• In patients with bilateral OME, 1.5% of untreated
ears and 2% of ears treated with tubes developed
severe atelectasis.
It may be that repeated bouts of AOM lead to
weakening and thinning of the membrane, which
allows atelectasis
• Sad and Berco showed destruction of the
collagen-containing fibrous layer of the tympanic
membrane in some ears with recurrent infection.
• Collagen destruction within the tympanic
membrane may lead to another complication of
• . Sad and Berco and Tos and Poulsen described four
stages of tympanic membrane retraction:
• stage I, retracted tympanic membrane;
• stage II, retraction with contact onto the incus;
• stage III, middle ear atelectasis; and
• stage IV, adhesive otitis media
• Middle ear atelectasis may be reversible with
ventilating tubes.
Sad showed that ventilating tubes improved the
state of atelectatic ears.
• Graham and Knight reported three cases in which
atelectatic tympanic membranes were restored to
their normal position
by administration of nitrous oxide during anesthesia
and insertion of a ventilating tube.
• Atelectasis and adhesive otitis media usually coexist
with OME,
• although OME may resolve in these ears, allowing
aeration of the attic and mastoid, but leaving a
collapsed middle ear.
In extreme cases, when hearing loss or ossicular
erosion occurs,
• a myringoplasty for the reinforcement of atelectatic
tympanic membrane may be indicated.
• Cholesteatomas may originate from deep
retraction pockets in which desquamated keratin
debris would not be cleared into the ear canal
These retraction pockets may occur in the pars
tensa or pars flaccida of atelectatic ears,
and should be considered precursors to
• Nonpneumatized mastoids may have a limited
ability to buffer pressure changes and
• can manifest as an atelectasis, a retraction pocket,
or a cholesteatoma
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