Positron emission tomography imaging of the kidneys

Positron emission tomography is a rapidly growing field of clinical nuclear medicine with most frequent applications in oncology and less frequent applications in cardiology and neurology. Recent developments have resulted in instruments that can image the whole body within 10–15 minutes, at a spatial resolution of 5–6 mm and counting sensitivities of 30 cps/Bq/ml.1 The advantage of PET is that the images are readily corrected for radioisotope decay, radiopharmaceutical dose, tissue attenuation and scatter. The concentration of the radiopharmaceutical can be calibrated and displayed in MBq/ml, kBq/ml/MBq injected dose or mEq/ml. These properties of PET make quantification of renal blood flow and glomerular filtration rate (GFR) straightforward and also make imaging of molecular targets including enzymes and receptors of the kidneys possible. Despite the many advantages, clinical applications of PET are still in their early development.