Semi-automatic 10/20 Identification Method for MRI-Free Probe Placement in Transcranial Brain Mapping Techniques

Abstract

The International 10/20 system is an important head-surface-based positioning system for transcranial brain mapping techniques, e.g., fNIRS and TMS. As guidance for probe placement, the 10/20 system permits both proper ROI coverage and spatial consistency among multiple subjects and experiments in a MRI-free context. However, the traditional manual approach to the identification of 10/20 landmarks faces problems in reliability and time cost. In this study, we propose a semi-automatic method to address these problems. First, a novel head surface reconstruction algorithm reconstructs head geometry from a set of points uniformly and sparsely sampled on the subject's head. Second, virtual 10/20 landmarks are determined on the reconstructed head surface in computational space. Finally, a visually-guided real-time navigation system guides the experimenter to each of the identified 10/20 landmarks on the physical head of the subject. Compared with the traditional manual approach, our proposed method provides a significant improvement both in reliability and time cost and thus could contribute to improving both the effectiveness and efficiency of 10/20-guided MRI-free probe placement.

Feasibility of Functional Near-Infrared Spectroscopy (fNIRS) to Investigate the Mirror Neuron System: An Experimental Study in a Real-Life Situation

“…When structural magnetic resonance imaging is not used, a MRI-free method, the international 10–20 system is adopted ( Jasper, 1958 ; Herwig et al, 2003 ). Previous findings have demonstrated that each 10–20 landmark on the scalp corresponds to a specific cortical structure and that there is a consistent correlation between scalp positions and underlying cerebral structures across subjects ( Myslobodsky et al, 1990 ; Okamoto et al, 2004 ; Xiao et al, 2017 ). Thus, according to the 10–20 system, attaining the approximate large-scale anatomical positions in which we are interested is achievable.…”

“…Considering the limited spatial coverage and spatial resolution, as well as the limited deep imaging capacity ( Vanderwert and Nelson, 2014 ; Xiao et al, 2017 ), it is fundamental and indispensable to investigate the feasibility of fNIRS to detect the MNS. However, few studies have examined the feasibility.…”

Augmented reality-based electrode guidance system for reliable electroencephalography

“…Considering the system configuration, the conventional 10–20 positioning systems is simple and inexpensive, but an unreliable electrode positioning can occur from the manual identification of the anatomical landmarks [ 7 , 8 , 13 – 15 ]. To address this issue, an extra device such as a vision-based position tracker, a commercial ultrasonic digitizer or a magnetic digitizer has been used so far [ 4 , 6 , 9 ]. Compared to those system, only an RGB-D camera is necessary in the proposed system.…”

“…Tsuzuki et al [ 5 ] proposed the MinR 10–20 system that used landmarks of nasion, right and left preauricular points and posterior point on the occipital protuberance. Xiao et al [ 6 ] proposed a semi-automatic 10–20 identification method using the virtual 10–20 landmark determination in the computational space of reconstructed head surface. The virtual landmarks were identified using a visually guided navigation system, which used a magnetic digitizer.…”

Neurobiological Basis of Brain Blood Oxygenation Responses Correlated with Cognitive Stroop Task Performance Before and After an Acute Bout of Aerobic Exercise

“…The Imagent manual (2005) provides the details of fNIRS as applied to the assessment of human brain. The fNIRS headcap was fastened to the subject’s head with Velcro straps, using the 10-20 International convention (Xiao et al, 2017) (Figure 2 A.). In total, 4 detectors and 24 channels were employed.…”