The vestibular system, also known as “the balance center,” is the part of our nervous system that enables us to stay upright relative to gravity and movement. If a dog has a problem associated with his or her balance, we often refer to this as “vestibular disease.” Or, vertigo essentially.
Make-up of the Vestibular System
The balance center is comprised of two main parts: the receiving component and the processing component. The receiving component refers to the nerve end behind the ear drum. The processing component is the brainstem that sends outputs to the eye, neck and limb muscles.
Clinical Signs of Vestibular Disease
There are a few different clinical signs that suggest your pet has vestibular disease, including:
- Head tilt
- Oscillatory movements of the eyes and eyelids (nystagmus)
- Imbalance/incoordination (ataxia)
- Tendency to fall or circle in the same direction
Further, dogs often walk as if they are “drunk”, using the walls for support. If you notice this type of behavior, or any of these clinical signs, meet with a neurologist. S/he can perform an examination to determine the cause.
During the examination, the neurologist will attempt to determine if the problem is associated with the peripheral structures (near the ear drum) or central structures (near the brainstem). The causes of these types of the disease are quite different and must be treated accordingly.
To differentiate the underlying cause, the neurologist will perform a complete neurologic examination. This includes:
- Gait analysis
- Proprioceptive testing to assess the accuracy of limb placement
- Eye movement evaluation
Peripheral Vestibular Disease
Dogs with peripheral vestibular disease often experience facial weakness and pupillary changes. This is because the nerve responsible for balance is near the nerve that controls the muscles of facial expression.
While some cases have an identifiable origin, others present with an unidentifiable cause. Veterinarians refer to this as idiopathic vestibular disease or “old dog vestibular syndrome,” which is like an acute onset of vertigo. This common condition improves with supportive care. Therefore, it must be differentiated from more sinister causes of vestibular disease seen in senior patients.
Other common causes include:
- Severe inner ear infections
- Other lesions affecting the vestibular nerve, such as tumors
Central Vestibular Disease
In general, central vestibular disease is considered more serious because it implies brain disease. Possible causes include:
- Certain cancers
- Autoimmune inflammation
- Metabolic and nutritional disorders
- Toxic levels of certain drugs (namely the antibiotic metronidazole)
First, our neurologists will identify the site of your dog’s vestibular disease and the potential causes. Next, s/he will guide you on the best course of action for your family. Treatment options range from supportive medical care with antibiotics to advanced imaging with an on-site high field MRI of the brain.
Vestibular disease is a common presentation with a scope of possible outcomes. These range from complete recovery without treatment to those requiring intensive intervention. If you notice any of these clinical signs in your pet, please arrange a consultation with our neurology department. Your primary veterinarian can submit a referral online or you can call us directly at 704-457-2300.