What is EEG?
Electroencephalography is a sensitive non-invasive method for studying the functional state of the brain.
Usually, "human" is added to this EEG definition at the end. But recently, the importance of pets in modern society has increased so much that loving owners pay a lot of attention to their health.
Why do EEG tests in animals?
For the diagnosis and treatment of pets, the most advanced and modern methods and achievements of medicine are used.
ECG, Holter monitoring, hearing and vision diagnostics, magnetic stimulation, and EEG.
Studies of the functional state of the brain in animals (more often for the presence of epilepsy) have recently been especially common in dogs, horses, pigs and some other types of pets.
There are special EEG recorders for animals developed nowadays.
Clinical EEG analysis provides diagnostic information in three main areas:
- statement of brain damage,
- prognosis of the course of the disease,
- localization of brain damage.
Indications for EEG in Animals
- Convulsive and syncopal states of various etiologies. Particular attention should be paid to epilepsy, which is a significant problem in the neurophysiology of small domestic animals.
- Circulatory disorders of the brain, hematomas, craniocerebral trauma. With this pathology, the EEG allows not only to determine the extent of the lesion, but also to predict the further development of the disease, as well as to evaluate the effectiveness of the treatment.
- Various neoplasms of the brain. In this case, EEG may be the first step in establishing the location of the pathological focus.
EEG Registration in animals
Electroencephalography is a safe and minimally invasive method. During the examination, only a slight sedation of the animal is required to prevent the appearance of myographic and other artifacts.
To record the electrical activity of the brain in animals, unlike humans, needle subdermal electrodes (disposable or sterilized) are often used. Such electrodes have a very low irritating effect, while at the same time providing a good recording quality.
During the EEG examination, provoking tests can be performed, such as flash stimulation with different frequency, duration and brightness of flashes.
EEG acquisition montage
When recording EEG in animals, usually no more than 8 channels are recorded using the international “10-20%” system. For reliable fastening of the electrodes, especially during long-term EEG examinations, they are additionally fixed with an elastic bandage.
EEG recording systems
EEG examinations in animals are usually carried out in veterinary clinics using stationary recorders.
However, more and more often recently (especially with the spread of the coronavirus pandemic and the strengthening of the self-isolation regime), examinations are carried out at home using wearable EEG recorders.
EEG video monitoring in animals
Less frequently, but still sometimes, animals are also subjected to long-term EEG video monitoring using wearable recorders.
With such a wearable recorder, the pet can move freely during the examination, and the recorded EEG data is simultaneously recorded in the built-in memory of the device and transmitted to the computer in real time.
Carrying out continued EEG monitoring using a self-powered EEG recorder worn on the body, internal memory and a wireless interface for real-time EEG transmission.
The power supply of this wireless wearable recorder is enough for 72 hours of continuous recording.
EEG video monitoring in animals is an indispensable and the only reliable way to compare the clinical behavior of the manifestation of an episode of a neurological disorder with the epileptic nature of this attack.
Examples of EEG recording in animals
What animal is EEG performed on?
Usually EEG in veterinary clinics is performed on dogs, cats, sometimes pigs, horses.
But sometimes there are requests for examination of rather exotic animals, for example, monkeys participating in a scientific experiment or zoo animals.
More recently, we were approached by researchers who are implementing a project for National Geographic on whale migration, which required the measurement of physiological parameters (ECG and EEG) in these animals. For such purposes, a wearable EEG recorder with built-in memory and autonomous power supply is ideal. However, it must first be reliably protected from water penetration.
Animal Seizure Video
Photos
Materials
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