ACCREDITED CPD - SURGERY
Article sponsored by Petcam®
such as granulomatous menigioencephalitis or central
vestibular disease. Detecting facial nerve damage prior
to surgery prevents its being considered a surgical complication.
Owners will often be concerned about the ability of the
animal to hear after the procedure especially when it has
to be performed bilaterally. This can be assessed with a
BAER test pre-operatively. However in reported owner
perceptions it has been found that there is not a noticeable loss of hearing after the procedure. The reality is
that the middle ear is already so damaged in the appropriate surgical candidate for the surgery, that the ability
to hear has already been damaged and the patients have
already adapted.
Otoscopy and culture are essential in the work up. This is
best done under sedation as the ears are often severely
inflamed and painful. The patients should be admitted
and once sedated, otoscopy can be performed and a
culture taken from the middle ear, via a myringotomy
if the tympanic membrane is still intact. The tympanic
is often found to be perforated and otitis media is assumed. A culture can be taken from the ear canal.
The next step is to perform radiographs or CT/MRI. Plain
film radiographs are most commonly used to evaluate
the outer and middle ear, but they are not considered
highly sensitive. They are however highly specific. CT
shows a higher sensitivity especially when combined
with plain film radiographs. MRI is once again highly sensitive and specific. In practice the first step is to perform
a standard ventro-dorsal radiograph (Fig 1) to assess the
ear canal and check for calcification of the ear canal. A
frontal open mouth view (Fig 1) is then used to assess the
tympanic bulla for fluid opacity and periosteal reaction,
which would indicate chronic otitis media in most cases.
In cases where there is calcification of the ear canal, periosteal reaction or fluid in the bulla then a TECA BO is indicated. These cases are unlikely to respond to medical
management as this can be considered an “end stage” ear.
Surgical procedure
Otitis externa and media is usually bilateral and cases often require surgery on both ears. It is possible to perform
both surgeries at the same time but this has little advantage to the patient. It prolongs the anaesthetic time and
doubles the pain experienced by the patient. Generally
the disease process has been going on for many months
to years and