Terminology and classification of seizures and epilepsy in veterinary patients

The classification of epileptic seizures and epilepsy is a controversial and dynamic topic that has undergone many iterations in human medicine. The International League against Epilepsy is a multinational organization that has formed a number of task forces and subcommittees to study this issue, and has ratified several reports outlining recommended terminology and classification schemes for human patients. Veterinary publications on this issue have generally adapted these schemes to fit small animal patients, but a formally endorsed system to classify seizures and epilepsy has never been developed for veterinary patients. This review outlines the classification systems that have been published for human patients and summarizes previous efforts by veterinary authors to utilize these methods. Finally, a set of definitions and terminology for use in veterinary patients is proposed, which includes a glossary of descriptive terminology for ictal semiology and a diagnostic scheme for classification of individual patients. This document is intended as a starting point of discussion, which will hopefully eventually result in a formally ratified document that will be useful for communication between health professionals, the design of clinical trials and for guiding treatment decisions and prognostication for veterinary patients with seizures.