![stereo eeg stereo eeg](https://els-jbs-prod-cdn.jbs.elsevierhealth.com/cms/attachment/ace3623a-7faf-409a-b092-11b62a46da1d/gr1.jpg)
SEEG avoids unnecessary craniotomies and the associated morbidity, hospital stay, and costs. SEEG provides sparser coverage spanning more, bilateral brain regions including deeper structures. Similarly, SEEG has been used effectively and successfully for the investigation of various types of epilepsies including temporal lobe epilepsy, extratemporal epilepsy, insular epilepsy, and various other types as summarized in a recently published review. A recent published systemic analysis has shown that SEEG efficiently identified epileptic zones in about 92% of the patients who underwent SEEG before surgery. SEEG electrodes are generally preferred over ECoG grids when the lateralization of the seizures is unknown or is expected to be in deeper brain structures, such as the insula or hippocampus. It has been widely used for the localization of the epileptic zones in different types of epilepsies. īeing a less invasive and effective alternative investigative tool, SEEG is used for recording the seizures with a three-dimensional analysis of the epileptic zone. Therefore, SEEG provides us with a powerful tool to study neuronal brain dynamics with high temporal and good spatial resolution. This precise process needs to be finished under general anesthesia. There are multiple contacts on the electrode thus, they can be used for recording the cortical and subcortical electrophysiological activity accurately.
![stereo eeg stereo eeg](https://i.ytimg.com/vi/n1E2dRYjdt8/maxresdefault.jpg)
Under the guidance of navigation, the electrode is implanted into the brain to directly record the electrical activity of the area. Stereo-EEG (SEEG) is used to determine the localization of the epileptic focus before surgery in pharmaco-resistant epileptic patients. However, direct observation of the brain deeper structure activity with EEG or fMRI measures is difficult. In most studies, functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) have been used to build neuronal networks. Functional neuroimaging by now has become a principal tool to study the neural correlates of consciousness. As the dose is increased, consciousness and voluntary responsiveness begin to fade. At a small dose, anesthetics first suppress thinking, focused attention, and working memory. Anesthetic agents comprise a wide variety of molecules acting on numerous receptors, channels, and other protein targets in the body. Recent studies of anesthesia mechanisms have focused on neuronal network and functional connectivity. The findings of the current study suggest SEEG as an effective tool for providing direct evidence of the anesthesia mechanism. When it was close to recovery, the correlation between the amygdala and ipsilateral temporal lobe significantly decreased followed by a considerable increase when awake. Results indicated that with the decrease of propofol concentration, power spectral density (PSD) in the delta band of the amygdala significantly decreased. The electrophysiology activity of the amygdala and other cortical areas from anesthesia to the recovery of consciousness was investigated using stereo-EEG (SEEG). The study was carried out in propofol-anesthetized five epileptic patients. Therefore, we present direct evidence in humans that SEEG indeed can be used to record cortical and subcortical electrophysiological activity during anesthesia. Here, we focus on the amygdala to investigate if SEEG can be used to detect cortical and subcortical electrophysiological activity in anesthetized epileptic patients. The stereo-electroencephalography (SEEG) recordings provide appropriate temporal and spatial resolution to study whole-brain dynamics however, the feasibility to detect subcortical signals during anesthesia still needs to be studied with clinical evidence.