A synthetic radioisotope is a radionuclide that is not found in nature: no natural process or mechanism exists which produces it, or it is so unstable that it decays away in a very short period of time. A radionuclide is an Atom with an unstable nucleus, which is a nucleus characterized by excess energy which is available to be imparted either to a newly-created Examples include technetium-95 and promethium-146. Technetium (tɛkˈniːʃɪəm is the lightest Chemical element with no Stable isotope. Promethium (prəˈmiːθiəm/ /proʊˈmiːθiəm is a Chemical element with the symbol Pm and Atomic number 61 Many of these are found in, and harvested from, spent nuclear fuel assemblies. Some must be manufactured in particle accelerators.
Some synthetic radioisotope are extracted from spent nuclear reactor fuel rods, which contain various fission products. This article is a subarticle of Nuclear power. A nuclear reactor is a device in which Nuclear chain reactions are initiated controlled For example, it is estimated that up to 1994, about 49,000 TBq (78 metric ton) of technetium was produced in nuclear reactors, which is by far the dominant source of terrestrial technetium. The becquerel (symbol Bq) is the SI derived unit of radioactivity. This article is about the tonne or metric ton For other tons see Ton. Technetium (tɛkˈniːʃɪəm is the lightest Chemical element with no Stable isotope. However, only a fraction of the production is used commercially. Other synthetic isotopes are produced in significant quantities by fission but are not yet being reclaimed. Other isotopes are manufactured by neutron irradiation of parent isotopes in a nuclear reactor (for example, Tc-97 can be made by neutron irradiation of Ru-96) or by bombarding parent isotopes with high energy particles from a particle accelerator. This article is a discussion of neutrons in general For the specific case of a neutron found outside the nucleus see Free neutron. 
Most synthetic radioisotopes are extremely radioactive and have a short half life. Half-Life (computer-game page here It's already listed in the disambiguation page Though a health hazard, radioactive materials have many medical and industrial uses.
The general field of nuclear medicine covers any use of radioisotopes for diagnosis or treatment. Nuclear medicine is a branch of Medicine and Medical imaging that uses the nuclear properties of matter in diagnosis and therapy
Radioactive tracer compounds are used to observe the function of various organs and body systems. These compounds use a chemical tracer which is attracted to or concentrated by the activity which is being studied. That chemical tracer incorporates a short lived radioactive isotope, usually one which emits a gamma ray which is energetic enough to travel through the body and be captured outside by a gamma camera to map the concentrations. Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions A gamma camera is a device used to image gamma radiation emitting radioisotopes a technique known as scintigraphy Gamma cameras and other similar detectors are highly efficient, and the tracer compounds are generally very effective at concentrating at the areas of interest, so the total amounts of radioactive material needed are very small.
The metastable nuclear isomer Tc-99m is a Gamma-emitter widely used for medical diagnostics because it has a short half-life of 6 hours, but can be easily made in the hospital using a "technetium-cow". A nuclear isomer is a Metastable state of an Atomic nucleus caused by the excitation of one or more of its Nucleons A nuclear isomer occupies A technetium-99m generator, or colloquially a technetium cow or moly cow, is a device used to extract the metastable isotope 99mTc of Technetium
Radiopharmaceuticals are any of a number of compounds using a radioisotope for medical treatment, usually by bringing the radioactive isotope to a high concentration in the body near a particular organ. Radiopharmacology is the study and preparation of radiopharmaceuticals, which are radioactive Pharmaceuticals Radiopharmaceuticals are used in the field For example, iodine-131 is used for treating some disorders and tumors of the thyroid gland. Iodine (ˈaɪədaɪn ˈaɪədɪn or /ˈaɪədiːn/ from ιώδης iodes "violet" is a Chemical element that has the symbol I and Atomic
Alpha particle, beta particle, and gamma ray radioactive emissions are industrially useful. Alpha particles (named after and denoted by the first letter in the Greek alphabet, α consist of two Protons and two Neutrons bound together into a Beta particles are high-energy high-speed Electrons or Positrons emitted by certain types of Radioactive nuclei such as Potassium -40 Gamma rays (denoted as &gamma) are a form of Electromagnetic radiation or light emission of frequencies produced by sub-atomic particle interactions Most sources of these are synthetic radioisotopes.