The metabolism is the transformation of energy and matter within the body. That process of chemical digestion and its related reactions is essentials for all living organisms.

A biokinetic model describes the time course of absorption, distribution, metabolism and excretion of material or radiation introduced into the body of an organism.

A bone scan or bone scintigraphy is used to in evaluate diseases of the skeletal system. Scintigraphic whole body bone imaging is a highly sensitive method to show changes in bone metabolism. Increased metabolic activity is seen as a hot spot.
The study requires the injection of a 99mTc-labeled radiopharmaceutical (most commonly methylene diphosphonate (MDP), hydroxymethylene diphosphonate (HMDP) or hydroxyethylene diphosphonate (HDP)). The activity administered for bone scanning is around 500 MBq (300-1100 MBq, 8-30 mCi), depending on age and weight of the patient. After 2-5 hours, the emitted gamma rays are detected by gamma cameras. The produced planar images include anterior and posterior views of the skeleton.
Multiphase bone scintigraphy is used to differentiate a bone process from tissue pathology. In some cases additional SPECT imaging is helpful to better characterize the presence, location and extent of disease.

A bone scintigraphy is a nuclear medical test used to detect increased calcium metabolisms with technetium labeled diphosphonates. Pathological bone processes present themselves primarily as activity enrichment.

See Bone Scan and Multiphase Bone Scintigraphy.

The cerebral blood pool can be imaged with single photon emission computed tomography (SPECT) and positron emission computer tomography (PET) techniques. The used radiopharmaceuticals are technetium-99m labeled red blood cells (RCBs) for SPECT and O-15 labeled water for PET imaging. Measured can be cerebral blood volume, brain perfusion and cerebral metabolism.

See Cerebral Metabolic Imaging, Fluorodeoxyglucose, Regional Cerebral Blood Flow, Coincidence Detection, Annihilation Coincidence Detection and Cyclotron.