STRUCTURAL BRAIN PATHOLOGY IN CANINE PRIMARY EPILEPSY: DOES IT EXIST?

摘要

It is difficult to obtain an accurate estimate of the prevalence of primary ('idiopathic') canine epilepsy, but review of the literature indicates that dogs with 'primary' epilepsy represent approximately half of all accessions of seizing dogs to veterinary hospitals. Review of the literature is further complicated by inconsistent case definition. In the past, the most common form of epilepsy was considered to be 'idiopathic' epilepsy, suspected in patients with generalized onset seizures, a young age of seizure onset (<5 years3), normal imaging findings and an absence of inter-ictal signs. Focal onset (or partial) seizures were considered uncommon, and indicative of underlying structural pathology. Careful questioning of the owner regarding the signs preceding generalized tonic clonic seizures, the use of visual recordings and EEG, have shown that focal onset seizures (with or without secondary generalization) are more common than previously thought. This highlights the difficulty in interpretation of some of the earlier case series for canine epilepsy, where diagnosis was often based on clinical presentation and inconsistent application of EEG or advanced brain imaging.Treatment of dogs with 'primary' epilepsy has variable success. Medical management is most commonly used; although a cornucopia of anti-epileptic drugs are available, the most commonly used first-line anti-epileptic drugs remain phenobarbital, potassiumbromide and benzodiazepines. Despite this, many dogs do not achieve satisfactory seizure control using medication and are regarded as having drug resistant epilepsy. Surgical options for treatment of dogs with drug resistant 'primary' epilepsy are currentlv limited. Transection of the corous callosum4 has been described, but is not widelv in use.