Your ear has been draining for the last 2 to 9 months,
you’re not exactly sure, but it’s been quite a while. It’s yellowish, smells like your feet and
your family has been bugging you to get it checked out and fixed, since the
site and smell ruins their appetites at the dinner table. You also notice your hearing isn’t the same;
in fact, your angered spouse is tired of repeating herself over and over and
over…well, you get the picture. As time
passes, the ear is beginning to hurt.
Your spouse drags you to your primary care doctor who you haven’t seen
in the past seven years (you forgot about that annual follow up), She takes a look into your ear, shakes her
head uttering the word, “huh,” and refers you to an ENT doctor. After round after round of telephone calls,
authorizations and pre-authorizations, appeals, etc. with the insurance company,
you finally get to see the ENT doctor who after cracking a few not-so-funny
jokes, announces with a little too much enthusiasm that you have a cholesteatoma. “A what?” you ask before the excitement
overcomes the giddy ENT doc. Such an
odd-sounding ailment. This leaves you
scratching your head, or your draining ear.
So what is a cholesteatoma? This term is actually a misnomer, for there
is no cholesterol and though the suffix “-oma” means “tumor,” this also is not
a tumor.
A cholesteatoma forms from either a defect such as a
perforation (hole) or retraction pocket in the tympanic membrane (ear
drum). The tympanic membrane is
comprised of several layers of different tissue types, and the most lateral
(outer) part is lined with tissue called squamous epithelium. This is the same tissue that lines the skin
on the rest of your body. The outer
layer of squamous epithelium naturally sloughs and falls off the body into the
environment. The cells of course are
microscopic so you won’t notice this natural sloughing. However, if this occurs within a deep
retraction pocket on the tympanic membrane or on the edges of a perforation on
the membrane, this squamous epithelium may accumulate where the cells group
together as a mass. As more sloughing
occurs, this mass can grow in size and can progress medially (inward) from its
source of origin.
Upon examining the ear, one may find a pearly white material
or mass in the ear. Sometimes there is
drainage of varying quality and consistency (purulent yellow, mucoid grayish, serous
clear to amber fluid, bloody drainage or if mixed with ear wax, brownish or
blackish) that may hide the cholesteatoma until the ear is debrided and
suctioned, typically under a microscope.
Less common is swelling behind the ear in the area of the mastoid. Sometimes a foul odor is noted due to
bacterial or fungal involvement.
Though a cholesteatoma is not a tumor, it can act as one by
the way it destroys surrounding tissue as just described. For some odd reason, a cholesteatoma creates
and releases osteolytic enzymes, substances that eat away at bone. As the figure shows, a cholesteatoma can
spread to other areas of the ear and beyond the ear. Some of the structure are listed below with
their potential effects:
-Mastoid air cells located behind the ear (behind the auricle
or outer ear—you know, those funnel shaped objects on each side of your head):
this can lead to bone destruction and infection in the mastoid called mastoiditis
(where the tissue behind the ear become red and swollen and painful, causing
the auricle to protrude forward).
-Ossicles (the bones of hearing connecting the tympanic
membrane to the cochlea): results in further hearing loss (more specifically, conductive
hearing loss, which is a result of sound not properly being transmitted
from the tympanic membrane to the ossicles to the cochlea). This sometimes is reversible with surgery and
reconstruction of the ossicular chain.
-Cochlea or inner ear: this leads to a sensorineural
hearing loss, which often is permanent.
In addition, tinnitus may occur, resulting in hearing ringing or
other various noises in your ear. Also
dizziness can occur since the cochlear shares fluid channels with the labyrinth
below.
-Labyrinth: this is a collection of fluid-filled sacs and
semi-circular canals and helps with you balance and sense of equilibrium. If a cholesteatoma erodes into this
structure, dizziness in the form of vertigo (spinning or movement sensation),
off-balance and sometimes nausea and vomiting can occur. And since the labyrinth communicates with the
cochlea, sensorineural hearing loss and tinnitus also can occur.
-Tegmen: the part of the base of skull separating the top of
the ear from the brain. If a
cholesteatoma violates this plate of bone and inflames the meninges, meningitis
occurs, resulting in fevers, headaches, neck pain and neck stiffness. If it progresses further into the brain, a
brain abscess can develop.
-Jugular vein and transverse sinus: the jugular vein runs
through the mastoid. This particular
portion of the vein is called the transverse sinus. Cholesteatoma involving this structure can
lead to a clot or thrombus, blocking flow of blood downward. This clot could extend further down the
jugular vein lower in the neck. These thrombi
(plural form of thrombus) can also become infected, which can lead to sepsis
(blood born infection leading to other parts of the body). If parts of the thrombus dislodged, they can
travel further down towards the heart and from their pumped to other areas of
the body. These dislodged clots are
known as emboli (plural of embolus).
Treatment centers on removing the cholesteatoma. If the cholesteatoma is small or confined to
a limited area, cleaning the sloughed material away may suffice, but regular
follow-ups are needed to prevent recurrence.
However, many situations require surgery to remove the cholesteatoma along
with any devitalized or infected structures damaged in the process. This often requires a mastoidetomy (drilling
out the mastoid bone through an incision behind the auricle) along with surgery
of the tympanic membrane and ossicles.
If possible, reconstruction of the ossicles can be done to improve
conductive hearing loss.
Thus, for persistent ear symptoms such as drainage, chronic
pain, hearing loss and particularly if you have balance or dizziness along with
those ear symptoms, have the ear fully evaluated to rule-out an underlying
cholesteatoma. Have that smelly,
draining ear treated correctly and restore sanity to the family dinner table.
©Randall S. Fong, M.D.
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