Analysis of a New Tool For Electrode Positioning on the Scalp According To the International 10/20 System

The emergence of non-invasive electromagnetic brain stimulation techniques, together with the improvement of electrophysiological recordings, has led to the need to increase the precision of the localization of cranial points close to their cortical target. In the clinical practice, the most common technique for locating there points on the scalp is the International 10/20 system and tape measure and a marker pen are used to carry out the marking process, before the placement of the electrodes. In this study, we have compared the marking for different electrophysiological tests between the conventional method and a new method based on the EPlacement device. The comparison was made taking into account the time spent on each test, the mean distance error per electrode, the direction of the error using the coordinate sign and, finally, a survey of healthcare staff to get their opinions on the 1S-EP and 2S-EP variants of EPlacement. The study involved 10 healthcare workers, 5 of whom had experience in conventional marking and 5 had experience in using the EPlacement device. 90 markings on dummies and 10 markings on volunteers were performed. Once each marking was completed on the dummies, the distances between the experimental points (marked with the EPlacement and tap measure) and the reference positions from 10/20 system determined by a 3D printed template were measured. The results show that with EPlacement, marking accuracy is increased, marking time is reduced, and healthcare personnel is receptive to adopting this technology. Keywords: 10/20, EEG, neurophysiology, nasion, inion, tragus, evoked potentials, error, 3D, EPlacement, dummy head, rTMS.