Image Based Mesh Generation for Realistic Simulation of the Transcranial Current Stimulation

R. Said[1], R. Cotton[1], P. Young[1], A. Datta[2] , M. Elwassif[2], and M. Bikson[2]
[1]Simpleware Ltd, Exeter, UK
[2]Department of Biomedical Eng, The City College of New York, USA
Published in 2008

Electrical stimulation of the brain involves the application of currents delivered through scalp electrodes to modulate brain activity, known as Transcranial Current Stimulation (TCS). A critical factor for TCS efficacy and safety is the “spatial focality” of induced neuronal modulation. Bikson and coauthors from the City College of New York have been investigating the impact of disc electrode configuration using computational modelling techniques. A range of configurations such as distantbipolar, adjacentbipolar, ringbelt, concentric ring and double concentric ring were simulated using COMSOL Multiphysics applying Laplace Equation on a rather simplified geometrical representation of the human head (i.e. four concentric spheres representing: brain tissue, cerebrospinal fluid, skull and the scalp respectively). More recent collaboration between CCNY and Simpleware Ltd has taken this research into another level by introducing more realistic geometry built based on high resolution MRI scan images (1 mm x 1 mm x 1mm spacing) using Simpleware’s ImageBased Meshing tools.