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Diffusion Tensor Magnetic Resonance Imaging in Chronic Spinal Cord Compression
Published on: May 7, 2019
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Anisotropic conductivity tensor imaging for transcranial direct current stimulation (tDCS) using magnetic resonance
Mun Bae Lee1, Hyung Joong Kim2, Eung Je Woo2
1Department of Mathematics, Konkuk University, Seoul, Korea.
Plos One
|May 16, 2018
Summary
This study introduces a novel method to visualize brain electrical properties non-invasively using transcranial direct current stimulation (tDCS) and MRI. The technique successfully maps conductivity and ion concentration in vivo, advancing brain stimulation research.
Area of Science:
- Neuroscience
- Biophysics
- Medical Imaging
Background:
- Transcranial direct current stimulation (tDCS) is a non-invasive brain stimulation technique.
- Current tDCS relies on computational models for optimal stimulation.
- Existing methods lack in-vivo visualization of electrical properties induced by tDCS.
Purpose of the Study:
- To develop a novel in-vivo method for visualizing brain electrical properties using tDCS.
- To reconstruct electrical anisotropic conductivity and ion concentration from tDCS-induced magnetic fields and diffusion measurements.
- To validate the proposed method in a canine brain model.
Main Methods:
- Measuring apparent diffusion coefficient (ADC) and tDCS-induced magnetic flux density.
- Utilizing a diffusion tensor J-substitution algorithm to reconstruct conductivity tensors.
- Recovering internal current density from measured magnetic fields.
Main Results:
- Successfully visualized electrical properties including anisotropic conductivity and ion concentration in vivo.
- Demonstrated the convergence of the iterative scheme to internal conductivity.
- Validated the method's efficacy in an anesthetized canine brain.
Conclusions:
- The proposed method enables non-invasive in-vivo visualization of brain electrical properties using tDCS.
- This technique offers a new tool for understanding brain function and optimizing tDCS protocols.
- Further research can explore applications in various neurological conditions.
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