ABSTRACT
This chapter briefly introduces the reader to the main components of an MRI scanner and to the technical challenges imposed by high-resolution MR microscopy. An important part is dedicated to the design and construction of radiofrequency coils dedicated to MRM. The placement of tuning and matching capacitors, as well as of other electrical components, close to the RF microcoil leads to significant susceptibility artifacts. Moving these elements farther away requires long coil leads which introduce other deleterious effects. Cryocooling the coil while maintaining the sample at room temperature is difficult for microcoils, as it implies significantly increasing the distance between the coil and the sample which leads to SNR deterioration. The development of micro-fluidic cooling devices appears to be a promising approach in terms of minimizing the coil-sample distance. Ideally imaging gradients should produce magnetic fields with intensities increasing linearly with distance from the center of the magnet (isocenter).
