Introduction to MRI Basics

The chapter aims to summarize all the basics of MR signal generation, MR contrasts, and spatial signal localization. The fundamental concepts are presented simply yet comprehensively, making it beneficial for beginners to grasp the mechanisms behind an MR image. The first part delves into the nuclear magnetic properties necessary to induce macroscopic magnetization in tissue when subjected to a Magnetic External Field. The second part discusses methods for stimulating tissues to obtain desired contrast information, whether T1, T2, or proton density dependent. The third part covers the Inverse Fourier Transform (IFT) and illustrates how to generate a signal containing spatial information using the three gradients of the magnetic field along perpendicular axes. Spin-echo and gradient-echo experiments, along with their corresponding sequences, are introduced.