Physics and applications of medical imaging

Medical imaging is the principal method for noninvasively obtaining anatomic and physiologic information about the human body. Imaging has experienced a quantum leap in technology and clinical applications over the past 25 years. This leap includes x-ray computed tomography (CT); emission computed tomography (SPECT and PET); magnetic-resonance imaging (MRI) and spectroscopy (MRS), including functional MRI (fMRI), and the networking of images in digital networks (PACS and IMACS). Even traditional projection x-ray imaging is undergoing a major change with the advent of digital x-ray image receptors. Images are important not only to the detection and diagnosis of disease and injury, but also to the design, delivery, and monitoring of treatment. The evolution of medical imaging is the product of physicists working in collaboration with engineers and physicians. Further advances are limited only by the creativity and imagination of these individuals. [S0034-6861(99)03702-2].