Magnetic Resonance Imaging (MRI)

Magnetic resonance imaging (MRI) is a technique that uses a strong static magnetic field and pulsed radiofrequency electromagnetic waves to elicit a radiofrequency response from the atomic nuclei in the body. A brief review of the spin and magnetic properties of the nucleus and the relationship between electricity and magnetism will provide a basis for understanding how MRI works. The spin angular momentum and the magnetic moments of the subatomic particles are closely linked. In particular MRI is particularly good for differentiating normal and abnormal soft-tissues which are generally indistinguishable using computed tomography. There are a multitude of manipulations of the method of applications of the radiofrequency pulses and variations in the sampling of the tissue responses that are used to reveal other useful tissue characteristics in MRI. The radiofrequency coil(s) used to generate the radiofrequency pulse and receive the magnetic resonance tissue signal are located along the inner surface of the gradient coils.