Cerebellar hypoplasia is a disease that denotes an inadequate development of the cerebellum, a section of the brainstem largely responsible for modulating motor impulses. Affected dogs and cats therefore fail to move normally, especially when it comes to maintaining normal balance, posture, and coordination.
Though cerebellar hypoplasia is most commonly regarded as a congenital hereditary disease in dogs, both pups and kittens can acquire this disease in utero if pregnant dogs and cats are infected by or vaccinated against specific infectious diseases (especially after panleukopenia infection or vaccination in cats).
Toxins, nutrient deficiencies, and infections can also lead to cerebellar hypoplasia in both dogs and cats.
The prognosis for patients with cerebellar hypoplasia depends on the degree to which they’re affected. Since the disease tends not to progress, affected pets with an ability to perform basic functions adequately enough to enjoy a good quality of life have an excellent prognosis.
A genetic disease known as cerebellar abiotrophy is also responsible for similar symptoms in both dogs and cats. This disease is distinct, however, in that it leads to the progressive death of specific neurons found in the cerebellum. As such, it leads to a gradual deterioration and carries a very poor prognosis.
Symptoms and Identification
Puppies affected by hereditary and/or congenital causes of cerebellar hypoplasia tend to display symptoms of this disease very early on, usually as soon as they’re able to ambulate. Kittens, however, will usually be symptomatic at birth.
Tremors, head bobbing, generalized lack of balance and coordination, exaggerated movements (especially when ambulating), and a wide stance are all observed.
Diagnosis is achieved primarily by noting the clinical signs, history of maternal infection or vaccination, and breed. Tests to rule out other causes of similar symptoms should always be undertaken. An MRI, in particular, may be of unique benefit.
The congenital, hereditary version of cerebellar hypoplasia observed in canines has been reported in Chow Chows. Another version has also been reported in Irish Setters and Wirehaired Fox Terriers.
Yet another hereditary version of cerebellar hypoplasia, known as the Dandy-Walker syndrome, is also presumed to have a genetic basis. This latter condition is technically referred to as “cerebellar ataxia” and is observed in toy Fox terriers.
There is no known treatment for this condition. Supportive care may ameliorate symptoms slightly in some cases.
Because of the dearth of treatment options, the cost of this disease is limited. It’s confined to the expenses associated with ruling out other possible diseases. However, an MRI, if elected, can prove very expensive, sometimes up to $2,000 to $4,000.
For hereditary forms of the disease, careful selection of breeding candidates is urged once this disease makes it presence known within the context of a breeding program. For other congenital forms of this disease (among others), avoiding vaccination, infection, malnutrition, and toxins during pregnancy is crucial.
"Cerebellar Disorders : Small Animals". The Merck Veterinary Manual. 2008. Accessed 2/24/13.
Coates, J.R. 1996. Weeble, wobble, roly, poly: a study of cerebellar disease. ACVIM-Proceedings of the 14th Annual Vet. Med. Forum. pp 684-687.