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CANINE TOTAL EAR CANAL
ABLATION IN THE DOG
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THE PET HEALTH LIBRARY
Total Ear Canal Ablation
and Ventral Bulla Osteotomy: The TECA Procedure
Sometimes an ear infection
is simply hopeless. Perhaps the organism growing is too resistant for
treatment. Perhaps the ear canal has actually mineralized from chronic
irritation. Perhaps the ear canal is so scarred and narrowed that external
cleaning is a useless activity. The bottom line is irreversible disease.
In these cases, all the diseased tissue including the entire ear canal,
bones of the middle ear, etc., are simply removed and the healthy tissue
around the ear is closed. This ends what has generally been a long tribulation
of pain, odor, ear cleaning, and expensive veterinary medications and rechecks.
The nightmare is over and life is able to go on.
This seems like a beautiful dream to the owner of the dog with
end-stage ears but happily it is a realistic dream so long as the process
and its associated risks are understood. This surgery essentially removes
the ear. The round bone behind the ear, called the tympanic bulla (reach
behind your own ear and feel yours right now if you are not sure what
the bullae are), is opened and flushed. A normal bulla is hollow and air-filled.
After years of otitis, the bulla is usually packed with pus, slime, or
cheesy infectious material that must be scooped or rinsed out. Many important
nerves travel through the area of the ear and these are exposed for damage
in surgery.
Preparing For the TECA
1. Radiographs to assess the tympanic bullae are helpful.
Sedation is generally required but it will be useful to know before
surgery how bad the bullae look, how narrowed the ear canals are and
if they are mineralized, if there is an obvious tumor growing in the
area. This helps confirm that this very aggressive surgery is really
appropriate for this patient.
2. The ear may be cultured prior to surgery. This helps
get the patient on an effective antibiotic right from the beginning.
Further cultures may still be required once the bullae are opened.
3. It is important to assess the cranial nerve function
of the patient prior to surgery. If these nerves are diseased prior to
surgery it is unlikely that they will regain function after surgery. Nerve
disease that results from surgery is usually temporary so it is important
to know if the nerve problems existed prior to surgery.
The facial nerve runs just near the base of the ear. This nerve
controls facial expression. A facial paralysis is not uncommon after long
standing ear disease. This means that the patient is slack-jawed on usually
one side of the face and may not be able to blink. After a time, the eye
usually retracts into the eye socket facilitating tear lubrication so
that the loss of blinking does not lead to eye damage. Initially, though,
lubricating gels are helpful to the eye.
Hearing is usually diminished after long term ear infections so
further hearing loss after ear ablation may not represent a dramatic change
in hearing. Most owners have a good sense of whether or not their pet
can hear so it is rarely necessary to formally test hearing. After the ears
are ablated, some hearing remains in many patients as sound waves can still
be transmitted through the tissues.
4. A complete blood panel and urinalysis are important prior
to any anesthetic procedure and this procedure is no exception.
What Happens In Surgery
The ears and head are shaved with the patient sleeping and the
ear canal is flushed one last time to remove as much infected material
as possible. This is done to minimize bacterial contamination of the
normal tissue.
Both the vertical and horizontal portions of the ear canal are
removed as one long intact curved cylinder. The bones of the middle
ear and the ear drum are removed as well.
The bone of the tympanic bulla is exposed and opened. Any material
is flushed out and the cellular lining of the bone is scraped away. Any
material left inside after closure will lead to chronic drainage of liquid
from the area of the incision. Often an external drain is left in place
during the healing period.
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normal ear
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dotted lines indicate where incision
is made
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ear canal is then removed from ear
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opening into ear is sewn shut
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Bandaging, oral antibiotics and pain medication can be expected
after surgery as can an Elizabethan collar to protect the delicate incisions
from scratching.
Potential Complications
The area of the tympanic bulla and the very bottom of the ear canal
share space with some important structures. These structures can easily
be damaged during surgery or by the inflammation that results during the
healing process.
The “great auricular vasculature” is located on the deep surface
of the ear canal being removed. If this vasculature is damaged, the pinna
(or furry ear flap) may lose part of its blood supply. Tissue dies along
the margin of the ear flap and trimming may be necessary.
The facial nerve is also located in this vicinity. If the facial
nerve is disturbed, a facial paralysis as described above may result.
This is one of the more common complications of TECA but is usually temporary.
(Facial paralysis after surgery is permanent in 10% to 15% of cases where
it occurs.)
The retroglenoid vein is located just below the tympanic bulla.
If this vein is broken, the resulting bleeding is not dangerous but will
obscure the visibility of the area making surgery more difficult.
Sometimes there is enough swelling in the area of the throat to
make breathing labored.
Approximately 5% to 10% of TECA patients experience chronic drainage
from the incision and require a second surgery of some sort to repair
the problem. Usually the drainage comes from salivary gland damage, residual
cells left in the tympanic bulla, remaining middle ear bone left behind,
or the production of more fluid than can drain normally into the throat
from the Eustachian tube (the natural connection between ear and throat).
In most cases, the results are near miraculous. Patients demonstrate
more energy now that their headaches are gone. There is no more odor,
ear cleaning or pain. This surgery requires advanced skill and referral
to a specialist is usually necessary.
Copyright 2004 - 2007 by Wendy Brooks,
DVM. Used with permission. All rights reserved.
This work was originally published by Veterinary Information
Network, Inc. (VIN) and is republished with VIN's permission.
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The above information is simply informational.
It's intent is not to replace the advice of a veterinarian nor to assist
you in making a diagnosis of your pet. Please consult with your own veterinarian
for confirmation of any diagnosis. Your pets life may depend on it.
