Under normal conditions, neurons carry out their activity thanks to the participation of support cells, to the release of excitatory and inhibitory neurotransmitters, to a correct level of electrolytes and oxygenation. Following anomalies in the balance of these factors, neuronal cells can activate in an uncontrolled manner and transmit the electrical stimulus to other groups of neurons as well.
makes it difficult to describe precise symptoms, which are manifested by all animals in seizures.
However, there is a classification that helps to group the possible manifestations:
- Focal seizures
They are given by a neuronal activity localized to a specific brain region and generally cause lateralized symptoms, therefore present in only one side of the animal. The clinical signs may include rhythmic movements of the facial muscles or of a single limb and can be associated with alterations of the autonomous system such as hypersalivation. In these cases the lesion responsible for the epileptic seizure will be located contralaterally to the clinical manifestations, but it must be remembered that a subsequent involvement of both cerebral hemispheres is possible in the case of stimulus propagation.
- Generalized seizures
It is the epileptic seizures that are most often detected in dogs and cats and indicate an involvement of both cerebral hemispheres. The resulting symptoms are loss of consciousness and station, tonic-clonic contractions of the skeletal muscles, pedaling movements, pupillary dilation, possible drooling and loss of urine and faeces.
The recognition of the event occurs due to a repetition of the symptoms in the same subject, indicating the activation of the same group of neurons, and in the succession of the phases that characterize this type of epileptic seizure.
In fact, we can recognize a prodromal phase of hours or days preceding the crisis and in which it is possible to observe changes in the behavior of the animal; the phase called aura, which precedes the crisis by seconds or minutes and is difficult to define in our animals, if not as a phase of agitation in which the owner realizes that something is about to happen. The ictal phase of the actual manifestation of the seizure follows; this phase is for the most part self-limiting and can last from 30 seconds to 3 minutes The last phase is called post-ictal and is the period of abnormal behavior following the seizure. The latter can last for hours or days and can be caused by disorientation, ataxia (loss of coordination), proprioceptive deficits (perception of the body in space), blindness and polyphagia (increased appetite).
When the duration of the seizures reaches and exceeds 5 minutes or we witness two or three events in the "span of half an hour" without recovery of the animal, we witness what is defined as status epilepticus. This form of manifestation therefore becomes an "emergency that must be managed as soon as possible because it can cause serious neurological damage.
Finally, epileptic seizures that repeat within 24 hours are defined as cluster or cluster seizures; in this case, however, a recovery of consciousness between one and the other is possible. However, it is necessary to notify your veterinarian as soon as possible.
For further information: Epilepsy , hepatic encephalopathy, hypoxia, uremic encephalopathy, electrolyte abnormalities) and exposure to toxins (ethylene glycol, organophosphates, metaldehyde, chocolate, strychnine, drugs and permethrin in cats).Structural epilepsy can be diagnosed with the help of advanced imaging such as magnetic resonance and cerebrospinal fluid analysis. This group includes vascular, infectious and inflammatory, traumatic causes, congenital anomalies, neoplasms and degenerative diseases.
The second group is given by idiopathic or functional epilepsy, which describes a cranial disorder whose precise cause cannot be diagnosed, but which alters the neuronal environment and its functionality. It is the most common cause in dogs and is often associated with genetic factors of the breed (Border Collie, Labrador Retriever, German Shepherd); it is also diagnosed in cats, but less frequently. The onset of idiopathic epilepsy is characterized by an age range of the animal of 6 months - 6 years and has a different course depending on the subject.
and the owner's description of the crisis. The general clinical examination, the in-depth neurological examination and the help of complete blood and urine tests and a screening for infectious diseases are also fundamental. Later on, advanced diagnostic tests are proposed such as magnetic resonance imaging to exclude the causes that alter the cranial structure.easily administered by the owner via the endorectal route, but this cannot be considered a therapy for repeated seizures over time. The diagnosis may lead to a specific therapy linked to the underlying cause or to the setting of antiepileptic therapy for long-term seizure control.
Finally, remember that in the case of epileptic seizures defined as clusters, that is repeated over 24 hours without recovery of consciousness, or epileptic states lasting more than 5 minutes, the situation becomes emergency and the animal must be immediately taken to a veterinary facility. .
