Syringomyelia is a neurologic condition that affects the brain and spinal cord. By far, the most common dog breed affected by syringomyelia is the Cavalier King Charles Spaniel, but other small dogs can also be affected. Weimaraners are also more prone to a type of syringomyelia, and though rare, cats can be affected, too.
So, what is syringomyelia? In short, it’s a neurologic condition that results in painful collections of cerebral spinal fluid (CSF). Cerebral spinal fluid is made in the ventricles of the brain. It bathes the structures of the central nervous system, providing nutrients, removing waste and providing cushion from jolting bumps. From its source in the brain, CSF flows through the middle of the spinal cord, then out and around the brain and spinal cord until it is eventually absorbed into the blood stream.
In the case of syringomyelia, there is a disturbance in the flow of CSF. Cavities of CSF form in the spinal cord, creating swelling. But because the spinal cord is surrounded by bony vertebrae, there is nowhere for the swelling to go, leading to pressure and pain.
Cavalier King Charles Spaniels in particular are prone to caudal fossa overcrowding, a deformity affecting an area of the skull that causes a disruption in the flow of CSF. You may also hear the term Chiari malformation (or Chiari-like malformation) to describe the condition of caudal fossa overcrowding, named for Austrian pathologist Dr. Hans Chiari, who categorized syringomyelia in human infants in the early 20th century. While similar, the condition in pets and humans is slightly different, so the term “Chiari-like malformation” is generally preferred for the description of the condition that leads to syringomyelia in Cavaliers and other small dog breeds.
Symptoms of syringomyelia
Symptoms of syringomyelia vary greatly depending on their severity. Some dogs have no symptoms at all. Other mild cases cause pain, which may fluctuate with changes in posture or excitement level. A common presentation of syringomyelia is a dog who scratches at her neck, chest or shoulder on one side for no apparent reason (such as skin disease). Dogs paw at these areas because of pain, similar to the way human patients report headaches, back and facial pain.
Severe cases will have more serious symptoms, such as weakness in the legs, pain in the extremities and facial paralysis.
Your vet can diagnose through magnetic resonance imaging (MRI), which can “see” the fluid pockets and can usually determine the underlying cause of syringomyelia as well.
How is syringomyelia treated?
Like the symptoms, treatment of syringomyelia will vary depending on the severity of the disease. Mild cases may not need treatment, but for more significant cases, both medical and surgical options are available.
- Oral medications, such as corticosteroids, diuretics and narcotics are used to control swelling, CSF production and pain, respectively.
- Surgery can sometimes be pursued to correct the underlying cause or to decompress the area of swelling. The earlier the condition is detected and surgically corrected, the better the pet’s prognosis.
If you suspect your pet might be dealing with syringomyelia, contact your vet immediately.
Have you ever had a pet with syringomyelia? Share your experience in the comments below to help other pet parents dealing with the diagnosis.