Clean Run - August 2017 - 64

If Your Dog Is Showing
Vestibular Signs
It can be quite stressful to witness the
onset of vestibular signs if your dog is severely affected; however, it's important
to keep a clear head. Remember your
dog is more anxious about the situation
than you are, so make sure to speak to
him in a calm and reassuring manner.
The primary goal during an initial vestibular episode is to prevent injury.
When dogs are trying to right themselves, they are prone to whipping their
head around and may hit the floor, furniture, or individuals who aren't quick
on their toes. Clear any furniture that
your dog may knock into out of the
immediate vicinity. Ideally, move the
dog to a rug that not only provides
some cushion, but also provides a
well-textured surface for them to brace
themselves if attempting to stand. Slick
flooring (hardwood, tile, and polished
cement) is a vestibular dog's worst enemy, as it will cause major difficulties
getting traction.
Since affected dogs tend to tilt to a
particular side, most will have a strong
preference on how they position themselves, tending to lay on a particular
side. Bolstering them with pillows, rolled
blankets, and cushions on the side they
are listing toward can help them sit up
in a more normal position.

Inner Ear Infection
Inner ear infection (otitis interna-media) is overall the most common cause of vestibular signs in veterinary medicine. Inflammation in the inner ear can very easily
extend into the vestibular organs, causing the whole spectrum of clinical signs from
mild head tilt to immobility. Progression may be slow or come on quite suddenly.
Signs that your pet may be dealing with the infection include an itchy/painful ear,
discharge from the ear canal, or any foul or uncharacteristic odor coming from the
ear. A clean ear canal does not necessarily exclude infection! Since the inner ear
lies behind the eardrum it is possible to have an inner ear infection without signs
in the external ear canal. The prognosis for recovery is favorable with appropriate
antibiotic therapy.
Idiopathic "Old Dog or Geriatric Onset" Vestibular Disease
While no longer called "Old Dog Vestibular Disease," as it's been described in younger dogs (and cats), this condition does tend to affect dogs later in life. For reasons
that are unclear, this condition appears to be an abrupt dysfunction of one of the
nerves carrying vestibular information from the inner ear to the brainstem. Characteristically, the signs come on suddenly and can be severe. Diagnostics such as
blood work, and imaging of the inner ear and brain are typically recommended.
Fortunately for dogs with this enigmatic condition, the prognosis tends to be favorable, with substantial improvement often seen in the first 48-72 hours.
Stroke
Stroke, or cerebrovascular disease, once thought to be a rare occurrence, is increasingly recognized as a cause of vestibular disease in older dogs. Signs are typically
similar to those seen in Idiopathic Vestibular Disease, with a sudden onset. Depending on the nature and extent of the infarct, signs may include other symptoms,
such as an involuntary tremor. While the prognosis tends to be favorable, every
effort should be made to determine the cause of the stroke and whether your dog
requires further treatments or therapies to prevent another event.
Hypothyroidism
One of the most common endocrine disorders, declining thyroid function has been
found to be associated with development of vestibular disease. Any dog, especially
older dogs, should be screened for low thyroid hormone levels. Hypothyroidism, if
present, is easily treated with hormone supplementation. Vestibular signs typically
will resolve with treatment.

Diagnosis
An examination by your primary care veterinarian or board-certified veterinary
neurologist can be very helpful in localizing whether your dog's signs are confined
to the vestibular system, or are representative of a more systemic issue. These professionals can also assess whether there is a more serious central nervous system
problem if they are seeing other neurologic signs. Following the initial examination screening, blood work is useful
in determining if there is any systemic
illness (liver disease, hypothyroidism,
etc.), which may be secondarily affecting the vestibular system.
If the initial blood work results show
your dog is systemically healthy, a determination of cause often comes down
to advanced imaging of the inner ear
and brain. Two advanced imaging stud-

Clean Run | August 17

Once your dog is safe and secure, it's
best to reach out to your primary care
veterinarian or seek out a board-certified veterinary neurologist. A boardcertified veterinary neurologist has
completed additional training through
the American College of Veterinary Internal Medicine (ACVIM), specializing
in surgical and medical small animal
neurology (ACVIM-Neurology). A clinic
visit can help determine likely causes
for your dog's signs and whether further testing is needed. Make sure to
bring any medications your dog is
currently taking, as some medications
can cause vestibular signs. Inform the
clinic staff of any previous or existing
medical issues as these may also provide important clues to the cause of
your dog's signs.

Common Causes of Vestibular Signs

Table of Contents for the Digital Edition of Clean Run - August 2017