Dense-Array EEG (DEEG)
Dense array EEG (DEEG), an advanced form of EEG, records electrical activity in the brain. In comparison with standard clinical EEG, DEEG uses many more electrodes, resulting in a more detailed picture of the brain. This in turn helps to more accurately diagnose and localize brain injuries.
DEEG has the advantage of being able to provide high spatial resolution because of its high channel count (up to 256). The density of electrodes, combined with high spatial resolution, enables it to accurately determine the topographical features of bioelectric activity in the brain. This resolution is particularly useful in experimental studies of the brain and in clinical applications of patients with focal epilepsy. In this way, the system is more accurate and precise than conventional EEG.
Compared to conventional EEG, dEEGs are more precise. They have the advantage of detecting focal abnormalities and detecting inter-ictal abnormalities. They may also make the presurgical evaluation less invasive. In clinical practice, they may be more accurate than a conventional 10-20 system.
A study showed that dEEG could detect interictal spikes in epilepsy patients with temporal lobe epilepsy. The study included 6 patients with subdural electrodes in the mesial temporal lobe. During this study, 45% of the spikes were, detected using dEEG, while 40% were undetectable.
Using the dEEG technique, a doctor can characterize traumatic and non-traumatic brain injuries in patients. In addition, it can detect demyelinating disorders, which damage the myelin sheath surrounding nerves in the brain and spinal cord. It can also provide an in-depth look into the brain and can help to localize seizure foci.
DEEG uses a high-resistance conductive ink-net substrate for electrodes and leads. Ink-Net has shown reduced cross-modal artifacts and signal degradation compared to conventional copper-wired electrodes. High-field scanners have a higher risk of heating artifacts. The Ink-Net has also proven to be safer for simultaneous dEEG/MRI scanning.
This method provides a high level of resolution. The electrodes are, spaced three centimeters apart. Moreover, the electrodes are placed at different levels of the head, allowing researchers to obtain an accurate picture of the brain’s activity. The data can be analyzed in a fast and efficient manner. Moreover, it also improves the efficiency of EEG labs by reducing channel count.
Another advantage of DEEG is that it is non-invasive. Patients can even undergo it in the comfort of their homes. Additionally, the technology is available to the public in many communities. Thus, it can be used to monitor the development of children with learning disabilities. In addition to providing better brain and mind function, this new technology can help diagnose conditions such as autism, depression, and ADD/ADHD.
It can detect and localize seizures more accurately than any other non-invasive technique
DEEG has the potential to detect seizures and localize them more accurately than any other non-invasive technique. It also has the potential to diagnose brain injury and helps physicians to direct surgery to affected areas. The resulting images provide an invaluable guide to therapy.
The use of dEEG and icEEG for simultaneous recording has increased the potential for this kind of analysis. This technique allows doctors to compare the dEEG and icEEG sensitivity to epileptic events in real time. The findings of this study suggest that dEEG is more sensitive to interictal spikes, which may provide a valuable clue to the location of the seizure onset.
In this study, the use of Deeg was, used to detect seizures in ten consecutive patients who had undergone a two-stage surgery to reduce the frequency of epilepsy. The patients were, followed up with long-term intracranial electroencephalography monitoring. During the first stage of the study, the patients had intracranial electroencephalograms (ICEEG) and MEG recordings before and after electrode implantation. These recordings were, used to compare the location of interictal MEG spike sources and iceEG ictal foci. Furthermore, they were, compared with the location of the earliest cortical origin of seizures. The sublobar concordance was, also measured.
The use of Deeg is essential in the evaluation of patients with epilepsy. It can help clinicians differentiate between seizures and non-epileptic events, as well as diagnose their severity and frequency. With these tests, physicians can identify the most appropriate treatment for their patients.
The Mayo Clinic in Florida employs a special intraoperative brain mapping tool to detect and localize seizures. This device uses 22 sensors to surround specific areas of the brain to accurately pinpoint seizure locations. It allows physicians to conduct dynamic testing throughout the procedure, without damaging eloquent tissue.
Magnetic resonance imaging (MRI) is another non-invasive technique, used to diagnose epilepsy. This type of imaging uses magnetic fields to visualize brain activity and determine areas of the brain that are prone to seizures. It is, usually performed in conjunction with EEG to improve detection of potential seizures. MEG can also help determine the cause of seizures.
The MEG technique maps the activity of each neuron. It also identifies abnormal brain activity associated with epilepsy and brain tumor. It also identifies the maximum involved area. These features enable doctors to more accurately treat the patient with the least amount of risk. However, the method has limitations. It is not always effective in detecting seizures, and the accuracy of this method depends on the type of epilepsy a patient has.
MEG is more sensitive than dEEG for detecting mesial temporal spikes. However, it has less sensitivity for deep sources of seizures than dEEG. The results from Huiskamp and colleagues (2010) show that whole head MEG detects 28% of mesial temporal spikes and 53% of lateral frontal spikes.
It can also characterize and localize traumatic and ischemic brain injury
In addition to epileptic seizures, Deeg can also be used to characterize and localize ischemic and traumatic brain injury. It has been shown that PDs are pervasive on electroencephalographic recordings of patients after acute brain injury. These episodes are termed ictal interictal continuum (IIC). Though no causal relationship has been established yet, the presence of distinct PD patterns is associated with hypoxic brain tissue.
