Cholesteatoma
Encyclopedia
Cholesteatoma is a destructive and expanding growth consisting of keratinizing squamous epithelium
in the middle ear and/or mastoid process
.
, which may also contain cholesterol
crystals. Often the debris is infected with Pseudomonas aeruginosa
or other bacteria or organisms.
If untreated, a cholesteatoma can eat into the three small bones located in the middle ear (the malleus
, incus
and stapes, collectively called ossicles
), which can result in nerve deterioration, deafness, imbalance and vertigo
. It can also affect and erode, through the enzyme
s it produces, the thin bone structure that isolates the top of the ear from the brain, as well as lay the covering of the brain open to infection with serious complications (rarely even death due to causing a brain abscess and septicemia).
Both the acquired as well as the congenital types of the disease can affect the facial nerve
that extends from the brain to the face and passes through the inner and middle ear and leaves at the anterior tip of the mastoid bone
, and then rises to the front of the ear and extends into the upper and lower face.
A history of ear infection or flooding of the ear during swimming should be taken seriously and investigated as cholesteatoma should be considered a possible outcome.
Common symptoms of cholesteatoma may include: Hearing loss, mucopurulent discharge
from the ear (usually brown/yellow) with a strong odor, bleeding from the ear, dizziness
, vertigo
, balance disruption, ear ache, headache
s or tinnitus
. There can also be facial nerve
weakness.
Cholesteatoma is an epidermoid cyst of the middle ear and/or mastoid. It developed as a consequence of eustachian tube dysfunction and chronic otitis media, secondary to retraction of squameous elements of the tympanic membrane into the middle ear space. Those squamous elements cause bone destruction secondary to its expanding nature and through enzymatic destruction.
Less commonly the disease may be congenital, when it grows from birth behind the eardrum. Congenital cholesteatomas are more often found in the anterior aspect of the ear drum, in contrast to acquired cholesteatomas that usually arise from the pars flaccida region of the ear drum in the posterior-superior aspect of the ear drum.
Squamous epithelium
In anatomy, squamous epithelium is an epithelium characterised by its most superficial layer consisting of flat, scale-like cells called squamous epithelial cells...
in the middle ear and/or mastoid process
Mastoid process
The mastoid process is a conical prominence projecting from the undersurface of the mastoid portion of the temporal bone. It is located just behind the external acoustic meatus, and lateral to the styloid process...
.
Signs and symptoms
The patient may have a recurrent ear discharge. Granulation tissue and a discharge (through a marginal perforation of the ear drum) may be seen on examination. A cholesteatoma cyst consists of desquamating (peeling) layers of scaly or keratinised (horny) layers of epitheliumEpithelium
Epithelium is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. Epithelial tissues line the cavities and surfaces of structures throughout the body, and also form many glands. Functions of epithelial cells include secretion, selective...
, which may also contain cholesterol
Cholesterol
Cholesterol is a complex isoprenoid. Specifically, it is a waxy steroid of fat that is produced in the liver or intestines. It is used to produce hormones and cell membranes and is transported in the blood plasma of all mammals. It is an essential structural component of mammalian cell membranes...
crystals. Often the debris is infected with Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
or other bacteria or organisms.
If untreated, a cholesteatoma can eat into the three small bones located in the middle ear (the malleus
Malleus
The malleus or hammer is a hammer-shaped small bone or ossicle of the middle ear which connects with the incus and is attached to the inner surface of the eardrum...
, incus
Incus
The incus or anvil is the anvil-shaped small bone or ossicle in themiddle ear. It connects the malleus to the stapes. It was first described by Alessandro Achillini of Bologna.The incus transmits sound vibrations from the malleus to the stapes....
and stapes, collectively called ossicles
Ossicles
The ossicles are the three smallest bones in the human body. They are contained within the middle ear space and serve to transmit sounds from the air to the fluid-filled labyrinth . The absence of the auditory ossicles would constitute a moderate-to-severe hearing loss...
), which can result in nerve deterioration, deafness, imbalance and vertigo
Vertigo (medical)
Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
. It can also affect and erode, through the enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
s it produces, the thin bone structure that isolates the top of the ear from the brain, as well as lay the covering of the brain open to infection with serious complications (rarely even death due to causing a brain abscess and septicemia).
Both the acquired as well as the congenital types of the disease can affect the facial nerve
Facial nerve
The facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...
that extends from the brain to the face and passes through the inner and middle ear and leaves at the anterior tip of the mastoid bone
Mastoid portion of the temporal bone
The mastoid portion of the temporal bone forms the posterior part of the temporal bone.- Surfaces :Its outer surface is rough, and gives attachment to the Occipitalis and Auricularis posterior...
, and then rises to the front of the ear and extends into the upper and lower face.
A history of ear infection or flooding of the ear during swimming should be taken seriously and investigated as cholesteatoma should be considered a possible outcome.
Common symptoms of cholesteatoma may include: Hearing loss, mucopurulent discharge
Mucopurulent discharge
Mucopurulent discharge is the emission or secretion of fluid containing mucus and pus from the eye, nose, cervix, vagina or other part of the body due to infection and inflammation....
from the ear (usually brown/yellow) with a strong odor, bleeding from the ear, dizziness
Dizziness
Dizziness refers to an impairment in spatial perception and stability. The term is somewhat imprecise. It can be used to mean vertigo, presyncope, disequilibrium, or a non-specific feeling such as giddiness or foolishness....
, vertigo
Vertigo (medical)
Vertigo is a type of dizziness, where there is a feeling of motion when one is stationary. The symptoms are due to a dysfunction of the vestibular system in the inner ear...
, balance disruption, ear ache, headache
Headache
A headache or cephalalgia is pain anywhere in the region of the head or neck. It can be a symptom of a number of different conditions of the head and neck. The brain tissue itself is not sensitive to pain because it lacks pain receptors. Rather, the pain is caused by disturbance of the...
s or tinnitus
Tinnitus
Tinnitus |ringing]]") is the perception of sound within the human ear in the absence of corresponding external sound.Tinnitus is not a disease, but a symptom that can result from a wide range of underlying causes: abnormally loud sounds in the ear canal for even the briefest period , ear...
. There can also be facial nerve
Facial nerve
The facial nerve is the seventh of twelve paired cranial nerves. It emerges from the brainstem between the pons and the medulla, and controls the muscles of facial expression, and functions in the conveyance of taste sensations from the anterior two-thirds of the tongue and oral cavity...
weakness.
Causes
There are two types: congenital and acquired. Acquired cholesteatomas, which are more common, can be caused by a tear or retraction of the ear drum.Cholesteatoma is an epidermoid cyst of the middle ear and/or mastoid. It developed as a consequence of eustachian tube dysfunction and chronic otitis media, secondary to retraction of squameous elements of the tympanic membrane into the middle ear space. Those squamous elements cause bone destruction secondary to its expanding nature and through enzymatic destruction.
Less commonly the disease may be congenital, when it grows from birth behind the eardrum. Congenital cholesteatomas are more often found in the anterior aspect of the ear drum, in contrast to acquired cholesteatomas that usually arise from the pars flaccida region of the ear drum in the posterior-superior aspect of the ear drum.
Pathophysiology
The status of cholesteatomas as tumors is currently unresolved. There is some evidence to support the hypothesis that cholesteatomas are low-grade tumors. However, recent studies have failed to show consistent DNA instability in cholesteatomas.Treatment
Surgery is performed to remove the sac of squamous debris and a mastoidectomy is performed. Cholesteatomas of the middle ear may be congenital and in some cases can be removed through the ear canal. The majority of cholesteatomas require that an incision be made behind the ear to expose the affected area adequately.Prognosis
Even after careful microscopic surgical removal, 10% to 20% of cholesteatomas may recur, which then require follow-up checks and/or treatment.External links
- http://www.cholesteatoma.net - Contains Stories From People Who've Had this Condition.
- http://www.entkent.com/cholesteatoma.html - Contains loads of information on Cholesteatomas.
- http://health.groups.yahoo.com/group/cholesteatoma/ - Support group with lots of information and personal experiences.
- http://www.earsurgery.org - Ear Surgery Information Center - very informative site