“Jake” was a lovely, happy, twelve-year-old yellow Labrador. You wouldn't have guessed that he was twelve, as he still behaved like a young pup! Poor old "Jake" was brought into the surgery as an emergency case as he had suddenly become extremely wobbly while he was out on his walk, and he was falling over to one side.
He was examined thoroughly, and a diagnosis of idiopathic vestibular disease was given.
The vestibular system is responsible for maintaining normal balance. This complex system is responsible for maintaining balance, posture, and normal stable orientation.
The vestibular system has two functional areas, central components located within the brain, and peripheral components, located within the inner and middle ear and the vestibulocochlear nerve.
The vestibular system located within the inner ear comprises a vestibule and three semi-circular canals. These structures work with the vestibulocochlear nerve and brain to sense, maintain, and regain balance.
Vestibular disease refers to a disease process of these structures causing a sudden disturbance of this balance. The problem may originate in the inner ear, vestibulocochlear nerve, or the brain. It is a common disease process in older dogs and is also referred to as “old dog vestibular syndrome” and “canine idiopathic vestibular syndrome”.
The clinical signs of vestibular disease are a sudden onset of loss of balance; a wobbly gait, disorientation; circling or deviating towards the side of the problem; a reluctance to stand up; a wide-based stance; a head tilt; irregular, jerking eye movements, called “nystagmus “and vomiting, due to motion sickness / dizziness.
Causes of vestibular disease include middle, or inner ear infections causing damage to the delicate sensors within the inner ear; central brain disease; some medical drugs that are toxic to the inner ear; trauma or injury, tumours pressing on these structures; Hypothyroidism; a cerebrovascular accident causing a brain infarct; or Idiopathic vestibular syndrome, which means that there is no obvious or known cause for the disorder.
Diagnosis of vestibular disease is based on a thorough medical history and the clinical signs, and if required the results of blood and urine tests, X-rays, and advanced tests and imaging. Vestibular disease can be caused by disease processes involving the peripheral components (the inner ear and vestibulocochlear nerve), or the central components (the parts of the hind brain). The most important initial ‘test’ is a thorough, neurological examination, as this is used to determine if the vestibular syndrome is peripheral or central and will indicate the necessary advised pathways for further investigations and treatments required. Referral may then be advised and required for further advanced tests and advanced imaging: magnetic resonance imaging (MRI) or computed tomography (CT) scanning can investigate for infection, tumours, or other abnormalities.
When no specific cause is found, the condition is called “idiopathic vestibular syndrome”. These cases often have transient symptoms and are distinguished by the sudden onset of clinical signs and a subsequent noted steady improvement, with thankfully often little, if any, medical intervention required. Idiopathic vestibular syndrome is the most common form of this disorder and is extremely common in older, ageing dogs.
Treatment options for vestibular disease are supportive, and if possible, are directed at the underlying cause, if one can be identified. In severe cases where a patient cannot stand and is vomiting severely, supportive therapy such as intravenous fluids and hospitalization may be required until the dog can eat and walk on its own again. If the dog is seriously disoriented and unable to stand or walk, they may be given safe sedatives to help them relax. Anti-nausea medications that help combat nausea or motion sickness are beneficial. Antibiotics may be used in cases having middle or inner ear infections, and anti-inflammatory treatments can also be used.
The prognosis for recovery from vestibular disease is very much dependent on the underlying cause of the clinical signs. The rate and extent of recovery is variable, and very difficult to predict.
The clinical signs associated with idiopathic vestibular disease are often most severe during the first twenty-four to forty-eight hours. Many pets then begin to improve within seventy-two hours. The head tilt and stumbling often improve over a seven to ten-day period, and patients recover within two to three weeks, although some cases will have residual symptoms, such as a head tilt or a mild unsteady gait for life. Treatment involves supportive care until the clinical signs resolve. Physiotherapy can be extremely useful and plays a part in the treatment of patients with vestibular disease since inactivity and recumbency results in decreased joint movement, stiffness and muscle weakness and contracture.
If the patient fails to improve or worsens, then a more severe disorder is then suspected, and referral for further advanced diagnostic testing and imaging is advised, and the patient's quality of life may have to be discussed.
Thankfully old” Jake” recovered well from his transient vestibular episode. He was given an anti-nausea treatment, and after a period of quiet rest at home, he was soon out and about on his usual walks again.
If you notice signs of vestibular disease do contact your vet surgery for an appointment as soon as possible, as these symptoms can be extremely distressing for the patient.