Unlike X-rays, ultrasound or other diagnostic tests that determine disease based on anatomy, nuclear medicine tests assess how organs function by administering small amounts of radioactive compounds called radiopharmaceuticals. These noninvasive, painless medical procedures provide physicians with vital information that enables them to diagnose and treat patients.

Quantitative Precision Nuclear Imaging imaging, provided by specialized nuclear medicine scanners, is a critical component of precision healthcare, helping doctors make the right treatment decisions based on a patient’s unique genetic makeup and medical history. More than 20 million patients undergo these diagnostic tests every year in the United States.

There are many factors that impact the quality of a nuclear medicine scan, including the physics of image formation, choice of image protocol parameters and the biology and physiology of the radiopharmaceutical being used. The most important physical factors are scatter, loss of spatial accuracy due to limited system resolution and partial volume effects (PVEs).

Nuclear Medicine Diagnostics: Accuracy, Safety, and Innovation

Scatter effects are primarily influenced by photon energy and source depth. In addition, sensitivity degradation of the detector can also lead to scatter artifacts. The choice of an imaging energy window also influences the accuracy and precision of quantitative estimates.

PVEs are characterized by the spill-out of activity into surrounding structures from a hot object of interest (typical of tumor imaging) or spill-over of activity into cold objects of interest (more typical in cardiac imaging). These artifacts can be corrected for using a variety of postprocessing techniques, but these methods require accurate measurements of an appropriate time-activity curve and careful patient positioning during the study.