Epilepsy

Epilepsy is seen in 1 to 2 % of all dogs and is without saying one of the most devastating diseases for both the dogs and owners. although it does occur in cats it has, compared to dogs, a very low prevalence. Epilepsy can be categorized based on aetiology as well as classification (1, 2). an epileptic or epileptiformic fits is the result of an abnormal electric activity in the cerebral cortex. if both hemispheres are involved it is classified as a generalised seizure and if only a small portion of the cerebral cortex is involved we tend to say that it is a partial or focal seizure.

generalised seizures or generalised epilepsy
The hallmark is the fact that both hemispheres are involved. the most seen form is the so-called generalised tonic-clonic seizure. the animal is suffering from a clear loss of consciousness. the seizure may present itself with a pre-ictale phase which consists of two parts. the prodrome is a phase in which the animal can be different (busier, quiet etc) and is followed by an aura. the prodrome may be absent, may be present for min- utes up to days. the aura normally lasts only a brief period and is directly followed by the actual seizure or ictus. During an aura the animal may vomit, look different, may seek attention etc. Both the prodrome and aura are often missed. During the ictus, often at night or early in the morning after sleep, the animal often falls to its side (or was already laying) and first will show a tonic period during which an ophistonus and exten- sion of all four legs may occur. it is directly followed by so-called clonic seizure that presents itself with biking or jerking movements with all legs. During the fit the animal may be vocal, salivate, urinate and defecate. the ictale phase can last from seconds to minutes. after the ictus a post-ictal phase is seen. this may take seconds up to days dur- ing which an animal can be for instance unable to walk, be ataxic, drowsy, aggressive, restless, etc. not rarely the animal may show some (temporarily) loss of memory. Both a long ictale phase as well as post-ictal phase are for both animals and owners a clear loss of quality of life (3). Besides this tonic-clonic seizure five other forms can be recognized (2). the second type (b) is a tonic seizure with again loss of consciousness but extreme muscle rigidity. the third form (c), a clonic seizure, consists of again loss of conscious- ness with only clonic movements with the legs. atonic seizures (d) present themselves with a sudden loss of muscle tone. a myoclonic seizure (e) presents itself with sudden jerks of one or more muscle groups. the most well know myoclonic epilepsy in dogs is Lafora in Beagles, Bassets and Dashunds which is triggered by sounds or light stimuli (4). the sixth form (f ) is an absence seizure which was formerly call ‘petit mal’. although they do occur they are difficult to recognize. [...]