The future of neurologic MR imaging.

One of the features that has characterized magnetic resonance since its first demonstration in 1946 has been its ability to reinvent itself and develop in new and surprising ways. One such change was the development of MR imaging; this technique has evolved in unpredictable directions. We will assume that the laws of physics, chemistry, engineering, biology, and, to a lesser extent, economics will not undergo any fundamental change in the foreseeable future, although anyone who had assumed this in the year 1900 would soon discover that s/he was mistaken. We will assume that there will be no shortage of clinical imagination in applying techniques so that the limitations specific to MR imaging are likely to arise from the physical, chemical, engineering, biological, and economic constraints of the technique itself. These will be expressed in achievable machine design and performance, which will form the focus of this discussion.