OPMs for epilepsy

For patients with focal refractory epilepsy, seizure freedom can be achieved through epilepsy surgery by removal of the epileptogenic zone (EZ). This requires the delineation of the EZ during the pre-surgical workup using non-invasive techniques such as Magneto/Electro-encephalography (MEG/EEG), or invasive recordings using intracranial electrodes (dEEG). The success of the pre-surgical workup, and thereby surgery, should be improved since seizure freedom is achieved in only two-thirds of the patients.
Newly developed MEG sensors, so-called Optically Pumped Magnetometers (OPMs), provide an unprecedented opportunity for epilepsy. These sensors are smaller, lighter, and cheaper, yet have a sensitivity that is comparable to that of cryogen-based Superconducting Quantum Interference Devices (SQUIDs). Importantly, they can be placed directly on the scalp, thereby improving the sensitivity to, and localisation accuracy of, epileptiform activity. Moreover, with a wearable OPM-based array, one could record during seizures. Together, this will not only improve diagnosis, but also the pre-surgical workup, thereby improving the chances of successful surgery and seizure freedom.
In this study we aim to demonstrate that novel MEG sensors can be used successfully in clinical practice, and to demonstrate their effectiveness as a powerful diagnostic tool in epilepsy.

Compared to SQUID-based MEG, OPMs are more sensitive to epileptiform activity from deeper brain stuctures, and in children. OPMs can also succesfully record seizure activity.

OPM-based and SQUID-based MEG data will be collected during a single visit to Amsterdam UMC - location VUmc