id="ulink_a93656f5-2074-522f-bca2-2f261757df4b">While most of the imaging community was geared toward the optimization of NMR scanners for humans, several research groups started to push the resolution of NMR imaging to the other extreme – the microscopic scale. This effort resulted in the 1986 publication of NMR images with structural features smaller than what can be recognized by the human eye (~100 microns) [16, 17]. This high-resolution imaging field has been termed as NMR microscopy (microscopic MRI, µMRI).
The latest “history” of this fascinating field is still being written as of today in the twenty-first century. NMR and MRI are very active and still evolving, with diverse applications in biology and medicine and various industries. There are many new and exciting developments in recent years, such as the optical pumping in NMR and MRI that improves SNR by more than 1000 times, compressed sensing that can shorten the experimental time tremendously, and exotic pulse sequences that fascinate our imagination. So far, a number of Nobel prizes have been awarded for discoveries related to NMR and MRI, including Rabi (1944) in physics, Bloch and Purcell (1952) in physics, Ernst (1991) in chemistry, Wüthrich (2002) in chemistry, and Lauterbur and Mansfield (2003) in physiology or medicine. By picking up this book, you are learning this fascinating phenomenon and joining this exciting field.
1.4 THE ORGANIZATION FOR A ONE-SEMESTER COURSE
This book is written ultimately for those who are interested in MRI. It contains the four essential components of MRI (Figure 1.6): the theory of physics that is the foundation of this fascinating phenomenon (Part I) [1, 2, 18, 19], the fundamental instrumentation and experimental techniques that facilitate the execution of this phenomenon (Part II) [1, 20], and two main applications – NMR spectroscopy (Part III) [21, 22, 23] and MRI (Part IV and Part V) [2, 4, 24]. Although each of these components could be taught in great detail in one or two semesters, the goal of this book is to cover the essential concepts in all four components in a typical one-semester course, hence the title of the book begins with Essential. I trust that you would be well prepared when you need to explore any topic deeper. In addition to the numerous equations, there are about 190 figures in the book that provide the graphical descriptions for the concepts.
Figure 1.6 Major conceptual components of NMR and MRI.
For the theory, I first give you the classical description of NMR, since it is easy to understand and visualize and provides a very useful first approximation. (If your goal is to do MRI on water-rich samples, the classical description is mostly sufficient.) I’ll then describe NMR in a compact (i.e., abbreviated) quantum mechanical form, so that you will be at least familiar with the basic approach and terminology of the mathematical treatment.
Sandwiched between the fundamental theory and practical applications are the NMR instrumentation and experimental techniques (Part II), which facilitate the execution of this phenomenon. For these techniques, I discuss the basic unit of the NMR system. (The additional hardware in MRI is discussed in Chapter 13.) These get-your-hands-dirty discussions on hardware and experimental techniques will let you see behind the equations and behind the black box, to understand how the experiments are carried out and what are the practical issues in spectroscopy and imaging. Although the hardware knowledge will be described in terms of NMR and MRI, it should be useful in other modern technologies involving electronics, computer applications, signal acquisition, and imaging.
The description of NMR spectroscopy aims to supply you with basic knowledge of the topic, which is more than what you can find from any of the MRI books. I truly believe that for any MRI researchers and technical personnel, the knowledge of NMR spectroscopy is critically important. The last two parts (IV and V) cover modern practice in MRI, with an emphasis on quantitative imaging, which is at the center of modern MRI research and diagnostics.
This book can be adapted for a one-semester course in several different formats. For the students who major in science (physics, chemistry, material science, engineering), a course should include all four components of MRI (theory, instrumentation and experiment, spectroscopy, imaging). For this format, one can teach either at the undergraduate senior level or the graduate level. If the students are mainly interested in imaging, a course can be tailored toward MRI, with just a brief introduction to NMR spectroscopy. One can teach this version of the course to students in medical school. Appendix 4 has several sample syllabi for teaching.
References
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15 15.
