Syringomyelia (SM) and the
Cavalier King Charles Spaniel
http://cavalierhealth.org/syringomyelia.htm
IN SHORT:
Syringomyelia (SM) is an extremely serious condition in which fluid-filled cavities develop within the spinal cord near the brain. It is also known as "neck scratcher's disease", because one of its common signs is scratching in the air near the neck.
The back half of the cavalier King Charles spaniel’s skull typically may be too small to accommodate all of the brain’s cerebellum, which may also be too large, and so it squeezes through the foramen magnum – the hole at the back of the skull – partially blocking the flow of cerebrospinal fluid (CSF) down the spinal cord. The variable pressure created by the abnormal flow of CSF is believed to create the SM cavities – called syrinx – in the spinal cord.
SM is rare in most breeds but has become very widespread in cavalier King Charles spaniels and the Brussels Griffon (Griffon Bruxellois). The number of diagnosed cases in cavaliers has increased dramatically since 2000. Researchers estimate that up to 95% of CKCSs may have Chiari-like malformation (CM or CLM) – also known as caudal occipital malformation syndrome (COMS) or occipital hypoplasia (OH), the skull bone malformation present in all cases and believed to be at least part of the cause of syringomyelia – and that more than 50% of cavaliers may have SM. The severity and extent of syringomyelia also appear to get worse in each succeeding generation of cavaliers. It is worldwide in scope and not limited to any country, breeding line, or kennel, and experts report that it is believed to be inherited in the cavalier.
Symptoms
Air Scrathing CavalierSM seldom can be detected in young puppies, as symptoms of it usually are not evident before the age of six months or years later.
Pain is the most important clinical sign of the disorder. Symptoms may vary widely among different dogs, but the earliest sign often is that the dog feels a hypersensitivity in its neck area, causing in some an uncontrollable urge to scratch at its neck and shoulders. Then usually follows severe pain around its head, neck causing it yelp or scream. As the disease progresses, it destroys portions of the cavalier's spinal cord, and is so painful that the affected dog may contort its neck and even sleep and eat only with its head held high. The dog's legs may become progressively weaker, so that walking becomes increasingly difficult. Some dogs deteriorate to the point of paralysis.
Diagnosis
The only accurate way of confirming diagnosis of the disease is through the use of magnetic resonance imaging (MRI) scanning, which can be an extremely costly procedure. The MRI allows the veterinary neurologist to study the spine for the presence of any abnormality which might obstruct the flow of the cerebrospinal fluid. Accurate MRI results require that the dog be anesthetized. Clinic charges for MRI examinations of canines have been known to vary from a rare discounted rate of $600.00 to over $2,000.00.
The names and locations of veterinary neurologists who are board certified by the American College of Veterinary Internal Medicine (ACVIM) are on our Neurologists webpage.
Another disorder common to cavaliers and with symptoms similar to SM is Primary Secretory Otitis Media (PSOM), which is a highly viscous mucus plug which fills the middle ear and causes the tympanic membrane to bulge. Because the pain and other sensations in the head and neck areas, resulting from PSOM, are so similar to symptoms due to SM, the possibility that the cavalier has PSOM and not SM should be determined before diagnosing SM.
Treatment
Treatment options for SM are very limited. Before the disease progresses to its severe form, the use of cortisteroids, such as prednisolone, or non-steroidal anti-inflammatory drugs (NSAIDs, such as Rimadyl and Metacam) may relieve the symptoms but not the deterioration. Cortisteroids have serious side effects, such as weight, gait, and skin changes, and harmful suppression of the immune system. Long term use of these drugs is not advised.
Anticonvulsants, such as gabapentin (Neurontin, Gabarone), have been successful in some more severe cases, but they may be very expensive. Pregabalin (Lyrica), amitriptyline (Elavil, Tryptizol, Laroxyl, Sarotex), and oral opioids (pethidine or methadone) are alternatives. Methylsulfonylmethane (MSM) is recommended by some veterinary neurologists as a dietary supplement.
Drugs which reduce the production of cerebrospinal fluid, including proton pump inhibitors such as omeprazole (Prilosec), and the diuretic, furosemide (Lasix, Diuride, Frudix, Frusemide), and spironolactone (Aldactone), may be useful, but clinical data on their use and effectiveness is lacking. Carbonic anhydrase inhibitors, such as acetazolamide (Diamox) also serve to decrease the flow of cerebrospinal fluid, but their adverse side effects of abdominal pain, lethargy, and weakness limit long term use.
Surgery to allow the cerebrospinal fluid to flow normally may be necessary to reduce the pain and deterioration. However, such surgeries are technically difficult and should be performed only by specialists. In some cases a shunt is installed. Although surgery often is successful, it is very expensive, and many dogs either have a recurrence of the disease or still show signs of pain and scratching. The most frequent reason for recurrence reportedly is the development of post-operative scar tissue. At least one neurologist has been inserting titanium mesh, in an effort to prevent such scar tissue from building up.
Breeders' Responsibilities
SM has a tendency to be more severe in each subsequent generation, and with an earlier onset. Breeders should follow the SM Breeding Protocol. The aim of the breeding protocol is to reduce the incidence of symptomatic syringomyelia in the cavalier breed, and not to create litters of puppies guaranteed not to have SM. The chance of producing an affected dog cannot be predicted without knowing the inheritance.
What You Can Do
• Donate to the Cavalier Health Fund.
• Donate by buying the book, For the love of Ollie.
• Participate in the Syringomyelia Cavalier Collection Scheme.
• Send MRI scans of cavaliers 5 years old or older and which do not have SM, along with MRIs of those dogs' family members, to Dr. Clare Rusbridge at
[email protected] Read about it here.
Ease your dog's symptoms by using a comfortable harness instead of a collar and leash. One of the best harnesses for cavaliers with CM/SM symptoms is the BRILLIANT K9 "Lucy Small" harness, available on Amazon. It is easy to put on and easy to take off. Watch the videos: "Opening the harness" and "Walking the dog with the harness".
Постепенно постараюсь перевести статью. Полный вариант статьи можно посмотреть по ссылке:
http://cavalierhealth.org/syringomyelia.htm#IN_DEPTH:
Буду благодарна за мнение.
