volume | PIER Journals

2009-06-04

A Simple Numerical Method to Compute the Signal-to-Noise Ratio of a Magnetic Resonance Imaging Surface Coil

Rafael Rojas Rodriguez,

Dr. Rafael Rojas Rodriguez

Universidad Autonoma Metropolitana Iztapalapa

México

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Alfredo O. Rodriguez Gonzalez

Dr. Alfredo O. Rodriguez Gonzalez

Electrical Engineering

Universidad Autonoma Metropolitana Iztapalapa

México

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Progress In Electromagnetics Research M, Vol. 7, 109-122, 2009

doi:10.2528/PIERM09040604

Abstract

The quality of a magnetic resonance image can be reliably measured by the signal-to-noise ratio. This widely accepted parameter is a function of the magnetic field generated by the coil and the electric field produced by the sample to be imaged. A simple numerical method is proposed to calculate the coil signal-to-noise ratio of a circular-shaped coil and a spherical phantom. The phantom is composed of two-concentric sphere simulating a brain-skull model. The electromagnetic fields produced were then numerically computed by solving Maxwell's equations with the finite element method implemented in a commercial software tool. The electric and magnetic fields were used to numerically determine the signal-to-noise ratio using the quasi-static approach. The numerical results demonstrated that this simple method is able to calcualte the signal-to-noise ratio of surface coils with simple coil geometries involving a simulated phantom.

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Rafael Rojas Rodriguez, and Alfredo O. Rodriguez Gonzalez, "A Simple Numerical Method to Compute the Signal-to-Noise Ratio of a Magnetic Resonance Imaging Surface Coil," Progress In Electromagnetics Research M, Vol. 7, 109-122, 2009.
doi:10.2528/PIERM09040604

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