Gradients: The heart of the MRI machine

Magnetic Resonance Imaging (MRI) machines are invariably grouped according to their main magnetic field strength. Yet far more important to their overall performance are their gradient coils. For it is these that determine the limitations of the crucial parameters, TE, image speed, even the acoustic noise produced, in every imaging sequence. To some degree, the gradients even determine what imaging sequences are possible of the system. For this reason it is vitally important that every purchaser and user of MRI machines have at least some grounding and background of gradient performance. To that end the following paper reviews the historic development, the current state of the art and future directions of what is still an active ongoing research program to improve the performance of these vital components of MRI machines.