High-resolution imaging with high and ultra high-field magnetic resonance imaging systems.

The development of noninvasive methods capable of affording ever higher resolution images is an ongoing major objective of scientific investigation for the benefit of both clinical medicine and neuroscience. Since its development in the early 1970s, magnetic resonance imaging (MRI) has remained a technology of choice for medical imaging development because of the wide range of potential clinical applications. Although conventional systems with field strengths of 1.0-1.5 T rapidly popularized MRI in general clinical practice in the 1980s, research investigations have focused on imaging yielding much higher anatomical resolution using high (3.0-4.0 T) and ultra high-field (7.0-9.0 T) systems. The substantial clinical experience with high and ultra high-field systems has made evident that there is a definite limit to which higher spatial resolution in and of itself will improve information for clinical judgment, rather, it is essential to develop the entire study as a whole, which would allow for the selection of an optimal combination of all the study elements, especially the appropriate contrast mechanism. This process is analogous to the development of suitable stains for a given pathologic process in histological techniques. In MRI, the natural physico-chemical MR contrast properties of tissues can be taken advantage of to achieve this goal, thereby obviating the need for administering contrast material to individuals.