Learning About Vestibular Disease in Dogs – Symptoms, Causes, and Treatment
As a fur parent, won’t you be concerned when your dog suddenly stumbles, has difficulty in walking, circles around, and finally collapses on the floor? Perhaps seizures or strokes would first come to your mind. But in many instances, it’s a case of vestibular disease in dogs. This is a lesser-known illness that can produce worrisome symptoms similar to those seen in seizures and strokes.
Worried about your dog experiencing vestibular disease? Or perhaps your dog has suffered from this illness before and you’re concerned about him getting a remission. In any case, we’ve compiled all the facts about this condition in this article!
We’ll define vestibular disease, outline its signs, symptoms, and diagnosis, and look into different treatment options in detail. You’ll also learn care tips for dogs with the disease.
Vestibular Disease in Dogs Defined
Vestibular disease is a sudden onset of non-progressive disturbance in your dog’s balance and mobility. It is caused by changes in his inner-ear sensory receptors. The condition may also stem from problems in the hindbrain.
Older dogs are known to get vestibular disease more often than younger pups. Hence, the condition is also referred to as old dog vestibular syndrome. Also, some cases of vestibular disease have no known causes. In this case, veterinarians refer to the condition as canine idiopathic vestibular syndrome.
How Does the Vestibular System Work?
Just like in humans, dogs have a vestibular system that controls their balance, orientation, proprioception, and mobility. The system’s components are located at the back of the brain and on the inner ear.
The inner ear is composed of two main organ groups, namely:
- Cochlea – This small organ physically resembles a snail and functions as the dog’s end hearing organ. It’s connected to the vestibulocochlear nerve that receives and transmits electrical impulses to the brain, enabling the dog to hear.
- The vestibule and semicircular canals – These organs regulate balance and maintain the dog’s orientation, proprioception, and equilibrium. Fluids inside the three semicircular canals let the brain detect how much the head is turning and which way it goes. The vestibule then sends these signals to the brain via the vestibulocochlear nerve.
Now, a dog’s hindbrain receives signals from the inner ear that allows your pet to understand where and what his position is. The hindbrain’s processing center also sends out messages to the dog’s entire body to help him keep upright.
Types and Causes of Vestibular Disease
Vestibular disease happens when there is a disturbance in the inner ears, the hindbrain, or both. This leads to two main types of the condition:
1. Peripheral Vestibular Disease
This condition happens when the inner ears and the connected organs experience infections, growths, or any other disturbance. This makes a dog lose his sense of balance and coordination at a sudden onset. Examples of conditions that may lead to peripheral vestibular disease include:
- Bacterial ear infections (Otitis media/Otitis interna)
- Fungal ear infections
- Inflammatory nasopharyngeal polyps
- Tumors
- Vestibular nerve problems
Bacterial infections are the most common cause of peripheral vestibular disease. Bacteria brought about by otitis media and/or interna produces toxins harmful to the inner ears, hence causing the dysfunction.
In some cases, veterinarians cannot pinpoint the problem or the exact cause of the condition. In this case, the dog’s proprioception and cranial nerves continue to function well. This type of peripheral vestibular disease is called idiopathic vestibular syndrome. It is thought that old age and genetics play a role in the development of such a type of peripheral vestibular disease.
2. Central Vestibular Disease
This refers to a vestibular disease that stems from infections in the hindbrain. In particular, the brainstem and/or the cerebellum areas are affected. These parts of the dog’s brain are credited with controlling balance, proprioception, orientation to space, and coordination.
Illnesses concerning the hindbrain may include:
- Widespread inflammation
- Lesions or neoplastic conditions leading to tumor growth
- Ingestion of toxins
- Canine stroke, hypothyroidism, hypertension, chronic kidney disease, hyperadrenocorticism, and diabetes mellitus
- Metronidazole toxicity
In-depth neurological examinations and MRIs can reveal conditions behind a central vestibular disease.
Signs and Symptoms of Vestibular Disease
Vestibular disease often presents with a sudden-onset mobility disruption. This can encompass a wide range of signs and symptoms, including the following:
- Head tilt – Leaning the head towards the problematic side
- Asymmetrical ataxia- Lack of muscle control resulting in a drunken-like gait, loss of balance, and falling over
- Nystagmus – Repetitive and uncontrolled eye movements
- Positional strabismus – Squinting in a downward position when the head’s position changes
- Circling in one direction
- Unusually wide stance
- Vomiting due to dizziness
Now, there are also certain symptom differences between peripheral and central vestibular disease. Assessing these differences will help your veterinarian determine the most accurate cause of vestibular disease in your dog:
Head Tilt
In peripheral vestibular disease, head tilt often leans to the problematic side where the inner ear infection or lesion. Meanwhile, head tilt can be seen on either side for central vestibular disease.
Nystagmus
Uncontrolled eye movements in peripheral vestibular disease are often seen horizontally or rotationally. Nystagmus fast phase is typically directed opposite the affected side.
Meanwhile, nystagmus in central vestibular disease can either be horizontal, vertical, or rotational. Nystagmus fast phase can also change direction depending on the head’s position. Vertical nystagmus is most prevalent and can accurately indicate a central vestibular disease.
Horner’s Syndrome
Horner’s Syndrome is a neurological disorder of the facial muscles and eyes. It usually affects one side of the head and face. The syndrome is characterized by:
- Ptosis – Drooping of the eyelid on the affected side
- Enophthalmos – Sunken appearance of the affected eye
- Miosis – Constriction of the pupil on the affected eye
- Conjunctival hyperemia – Dogs have a third eyelid that helps keep their eyes moist [1]. Now this condition, also called prolapse of the third eyelid, refers to the red and raised appearance of the dog’s third eyelid.
Horner’s Syndrome is typically seen in peripheral vestibular disease. Rarely does it affect a dog with central vestibular disease.
Mental Status
Dogs with peripheral vestibular disease remain alert and do not experience changes in their mental status. However, those with central vestibular disease will appear stuporous or depressed. Some dogs may even fall into a coma.
How Do Vets Diagnose the Condition?
The veterinarian will carefully evaluate your dog through a physical examination, looking for clinical signs that could indicate vestibular disease. Urine and blood tests are typically ordered. Other diagnostic tests your dog’s vet may consider include:
- Radiograph of the head to assess the middle and inner ears
- Magnetic Resonance Imaging (MRI) and CT scans to check for any tumors or abnormal growths in the brain
- Brainstem Auditory Evoked Response (BAER), an advanced test to determine the position of a suspected brainstem lesion for pets with central vestibular disease
- Taking samples of cerebrospinal fluid to check for infection and inflammation in the brain
If your dog’s veterinarian doesn’t detect any abnormalities, growths, or infections, he may conclude that the case is idiopathic (has an unknown cause) in nature. Vets typically use the following criteria to declare an idiopathic vestibular disease diagnosis:
- The dog is already old;
- There is a sudden onset of signs suggestive of peripheral vestibular disease;
- There are no ear infections, trauma, ototoxicity, medication overdose, hypothyroidism, or other conditions that may lead to the disease;
- A marked improvement in the dog’s condition within 72 hours
- Signs continue to improve in 1-2 weeks (although the head tilt typically persists)
According to the results of this retrospective study, idiopathic vestibular disease is a common occurrence and has been shown to appear in older dogs as compared to those with ear infections at any age.
Proper diagnosis is necessary to rule out a stroke or any other condition that may falsely present as vestibular disease in dogs.
Treating Vestibular Disease in Dogs
Treatment for vestibular disease is often direct to correcting or eradicating an identified underlying cause. Once the cause is treated, the symptoms of vestibular disease often subside as well.
Here are the treatment options for different underlying causes of vestibular disease in dogs:
Bacterial Ear Infections
Antibiotics such as amoxicillin-clavulanate, clindamycin, or enrofloxacin may be prescribed for a few weeks if your dog has bacterial otitis interna. Your dog’s vet will decide how long the antibiotics must be given, but the minimum recommendation is 6-8 weeks of continuous treatment. Full ear cleaning will also be done.
To know more about this Bacterial ear infection and how you can treat it in the comfort of your home, you can check out our other article about it here: Complete Guide to Treating Dog Ear Infection with Home Remedies
Fungal Ear Infections
Outer ear infections caused by yeast may be treated with topical antifungals such as ketoconazole or miconazole. Meanwhile, deeper fungal infections are treated with Itraconazole. The vet will also clean your dog’s entire ear canal.
Inflammatory Nasopharyngeal Polyps
Nasopharyngeal polyps may often be seen in cats, but it does happen to dogs as well. In cats, the polyps extend to the back of the throat. But in dogs, the polyps go into the ear canal, making them a causative factor in developing vestibular disease. Polyps in dogs are thankfully rare.
Polyps are removed through a procedure called Total Ear Canal Ablation and Bulla Osteotomy. This procedure may be complex and long, requiring pain medications during the recovery process.
Metronidazole Toxicity
Metronidazole toxicity is treated by stopping the medication immediately and providing diazepam therapy. An initial intravenous bolus of IV metronidazole Is given. Then, oral diazepam is given three times a day for three days to stop the harmful neurological effects of metronidazole toxicity in dogs.
Tumors
Dogs experiencing vestibular disease due to tumors in the ears or on the brain itself are treated by both medical and surgical management. Your dog’s vet will determine the best course of treatment depending on the tumor type and its location.
Idiopathic Vestibular Disease Management
Supportive care is given to dogs with unknown causes of vestibular disease. Dogs are typically hospitalized and given intravenous fluids and anti-nausea medication. This kind of management is done because most dogs feel nauseous, dizzy, and have experienced bouts of vomiting during the illness’s acute onset.
Dogs are deemed fit for discharge when they can already eat, drink, and move around without significant assistance. They can then continue recovering from vestibular disease at home. You should monitor your dog at home and provide assistive care as he recalibrates his vestibular system.
Note that any kind of vestibular disease is at its most severe during the first 24 to 48 hours. This is why many veterinarians advise that affected dogs be hospitalized especially if they present with moderate to severe symptoms.
Caring for your Dog with Vestibular Disease
Help your dog ease his symptoms by caring for him the right way at home. Here are tips for looking after your pet as he recovers from vestibular disease in dogs:
Keep your dog safe.
Your dog’s balance is still problematic during the first few days of the condition. Hence, you must keep your dog safe by providing him a smaller space to wander around at home. Keep your dog away from stairs and clear the areas where he wanders around to avoid tripping over and falling. It’s also a good idea to pad your dog’s space as well.
Assist your dog in feeding, drinking, and toileting.
You may hand-feed your dog initially to help him ease back into his typical eating and drinking habits. Keep his food and water bowls nearby and push them against the wall so that they will not drift. Also, give your dog soft and easily-digestible food. For toileting, use a harness or a towel sling to provide crucial support to your dog.
Make your dog feel comfortable.
Your dog may have difficulty in sleeping, so place a rolled-up blanket under his head for extra support. Also, he may suffer from canine separation anxiety [2] as he treads through the difficult process of recovery, so always be at your dog’s side as much as possible!
Avoid carrying your dog all the time.
Let your dog navigate his space freely to help recalibrate his vestibular system. Just guide him using a harness or place your hands on either side of your dog’s body as he walks.
The Bottomline
Vestibular disease in dogs may seem scary at first. But when diagnosed correctly and given proper treatment and attention, your dog will recover well in a few weeks! You and your veterinarian will collaborate to keep your dog safe, well-nourished, and comfortable as he treads the road to recovery.
References:
- Dunbar, C. (2018). Dogs: 101 amazing dog fun facts and trivia for kids.
- Miller, P. (2008). The power of positive dog training (2nd ed.). Wiley Publishing Inc.
- Pancotto T., (2016). Central vs. Peripheral Vestibular Diseases. Regional College of Veterinary Medicine. https://www.fetchdvm360.com/wp-content/uploads/2016/04/CVCVB_2016_neurology.pdf
- Tauro, A., Beltran, E., Cherubini, G. B., Coelho, A. T., Wessmann, A., Driver, C. J., & Rusbridge, C. J. (2018). Metronidazole-induced neurotoxicity in 26 dogs. Australian veterinary journal, 96(12), 495–501. https://pubmed.ncbi.nlm.nih.gov/30478843/
- Webb A., (2009). Brainstem auditory evoked response (BAER) testing in animals. NCBI. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2643461/
- Orlandi R., Gutierrez-Quintana R., Carletti B., Cooper C., Brocal J., Silva S., Gonçalves R., (2020). Clinical signs, MRI findings and outcome in dogs with peripheral vestibular disease: a retrospective study. NCBI. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7249679/
- American College of Veterinary Surgeons. Nasopharyngeal Polyps. ACVS Org. https://www.acvs.org/small-animal/nasopharyngeal-polyps
- American College of Veterinary Surgeons. Otitis Externa. ACVS Org. https://www.acvs.org/small-animal/otitis-externa
- LeCouteur R., (2009). Vestibular disorders of dogs and cats. https://www.dvm360.com/view/vestibular-disorders-dogs-and-cats-proceedings
