All about syringomyelia in dogs: signs, tests, treatment

Syringomyelia is a neurological condition that has gained attention in recent years, especially after being highlighted in the BBC’s Pedigree Dogs Exposed documentary in 2008. It is notably common in Cavalier King Charles Spaniel puppies, where harmful breeding practices have contributed to its prevalence.

However, syringomyelia is not limited to Cavalier King Charles Spaniels. This non-contagious condition, caused by anatomical conformation rather than an infectious disease, can affect dogs of various breeds, especially smaller pedigree breeds. It is often inherited when breeding lines with particular skull and brain conformations are maintained.

What is syringomyelia?

Syringomyelia occurs when fluid-filled cavities, called syringes, form within the spinal cord. This usually results from a malformation known as Chiari-like malformation, characterised by a mismatch between brain size and skull size, leading to cerebrospinal fluid (CSF) flow obstruction at the base of the skull.

This condition is congenital and more commonly seen in small breeds due to their skull structure. Syringomyelia is progressive and can cause intense pain, headaches, stiffness in the neck, back, and limbs, as well as weakness or numbness in limbs. In severe cases, it may affect bladder or bowel control, body temperature regulation, and cause overheating.

Because of the chronic, painful nature of syringomyelia, dogs affected by it should not be bred to prevent passing the condition to offspring.

Symptoms of syringomyelia in dogs

Dogs with syringomyelia often display clear signs of discomfort. Sensitivity or refusal to be touched around the head and neck, reluctance to wear collars or be on leads, and defensive reactions when these areas are approached may be observed.

Pain may worsen with exposure to extreme temperatures or after resting, as certain sleeping positions can exacerbate discomfort. A dog sleeping with its head elevated without apparent reason may indicate syringomyelia.

Commonly, dogs may scratch or paw at their head or neck, often on one side only. Advanced cases might show neurological signs such as difficulty walking, limb weakness or tremors, deafness, or nerve paralysis.

Testing for syringomyelia

If syringomyelia is suspected, a veterinary assessment involving Magnetic Resonance Imaging (MRI) is the gold standard for diagnosis. MRI reveals the presence of syringes and helps identify underlying structural abnormalities like Chiari-like malformation.

Because MRI equipment is expensive and not generally available in all veterinary practices, referral to specialist centres may be necessary, which can be costly.

MRI also helps breeders decide if a dog is suitable for breeding without a high risk of passing on syringomyelia.

Treating syringomyelia in dogs

Treatment depends on severity but focuses mainly on managing symptoms and quality of life.

• Surgical intervention can relieve pressure by removing part of the occipital bone, though it's usually reserved for severe, painful cases and results may vary.
• Corticosteroids reduce fluid build-up and inflammation but may have side effects with long-term use.
• Non-steroidal pain medications and anticonvulsants can be effective alternatives for managing pain and neurological symptoms.
• Cerebrospinal fluid reducing drugs help to limit fluid production, reducing the formation of syringes.

Prognosis

Syringomyelia cannot be fully cured, but its symptoms can often be managed. The condition's impact varies from mild discomfort to severe neurological impairment. In some cases, if pain is unbearable and quality of life is poor, humane euthanasia may be considered.

Owners and breeders should ensure affected dogs or lines prone to syringomyelia are not bred to prevent further suffering.

If you have concerns about syringomyelia in your dog or a dog you’re considering, consult your vet promptly for advice and diagnosis.