As functional imaging becomes increasingly important in radiology, practitioners in a wide range of disciplines need to understand more about the quantitive aspects of physiology and pathophysiology. In straightforward language, this book integrates the principles and mathematics ofmeasurements with physiological systems to which the quantitive problems are applied. Although there is an emphasis on clinical management with radionuclides and quantitive procedures in nuclear medicine, this book has been written with all practitioners in mind and also therefore embracestechniques based on non-radioactive indicators, including contrast agents used in CT, MRI, and ultrasound. Starting from basic mathematics, the book describes the measurement of fundamental physiological variables, like transit time, clearance, and blood flow, and goes on to cover the perpheralcirculation and microvascular solute transfer, the pharmacokinetics of agents routinely used in nuclear medicine, as well as scintillation detectors, data processing, and quantification. In separate chapters, measurements in the heart, lung, gastrointestinal tract, liver, blood, genitourinary tract,brain, and skeleton are discussed, and the book finishes with a chapter on questions and worked answers.