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Chapter 1 Mathematics and Physics of Emerging Biomedical Imaging 1 . 1 Introduction and Summary

Recent advances in imaging technology allow evaluation of biologic processes and events as they occur in vivo. For example, new magnetic resonance and radioisotope imaging methods reflect anatomy and dynamic body functions heretofore discerned only from textbook illustrations. These new methods give functional images of blood flow and metabolism essential to diagnoses and to research on the brain, heart, liver, kidneys, bone, and other organs of the human body. Studies of such phenomena as brain atrophy during normal and abnormal aging (Figure 1.1) have been aided by advances in the resolution of magnetic resonance imaging (MRI), while advanced biomedical imaging techniques have improved care procedures in difficult medical situations such as brain surgery (Plate 1.1; plates appear after p. 12). In cancer research the new methods have enabled studies of the efficacy of therapy without the need for biopsy or the anguish of waiting for morbid signs of recurrence (Plate 1.2 and Figure 1.2).