Magnetic Resonance Electrical Impedance Tomography

Area of Science:

• Biomedical Engineering
• Medical Imaging
• Electrical Engineering

Background:

• Magnetic Resonance Electrical Impedance Tomography (MREIT) is an advanced bioimpedance imaging method developed since the early 1990s.
• It measures low-frequency (<1 kHz) tissue electrical properties, crucial for understanding cell structure and ionic composition for diagnostics.
• MREIT utilizes MRI to reconstruct electrical property distributions from magnetic flux density data induced by administered currents.

Purpose of the Study:

• To provide a comprehensive overview of MREIT image reconstruction algorithms.
• To detail both isotropic and anisotropic conductivity reconstruction methods.
• To introduce the Diffusion Tensor MREIT (DT-MREIT) for anisotropic tissue property imaging.

Main Methods:

• MREIT employs MRI to measure magnetic flux density changes caused by exogenous current injection.
• Reconstruction of electrical conductivity typically requires at least two linearly independent current administrations.
• The chapter explores various reconstruction algorithms, including those for isotropic and anisotropic conductivity.

Main Results:

• MREIT has demonstrated potential in imaging electrical conductivity in tissues like the brain and muscle.
• The technique has been investigated in disease models, including cerebral ischemia and early tumor detection.
• The development of DT-MREIT offers a practical approach for anisotropic tissue property imaging.

Conclusions:

• MREIT is a powerful tool for high-resolution bioimpedance imaging with significant diagnostic potential.
• Understanding and applying various MREIT reconstruction algorithms are key to its successful implementation.
• The advancement to DT-MREIT expands MREIT's capability to image complex anisotropic tissue properties.