To understand how radioisotopes are used in nuclear medicine, we first have to understand what they are and how they work alone. Radioisotopes are atoms that contain an unstable combination of protons and neutrons. Sometimes, the combination can occur naturally, like radium-226, or it can be produced artificially by altering the atoms. Atoms that contain that natural unstable combination emit radiation from the alpha, beta, or gamma rays. Using radioisotopes in the medical field allows doctors to look inside the organs to find a potential problem.
One way that radioisotopes help in the medical world is by providing PET scans. PET scans uses radiation to produce 3-dementional, color images of the functional processes within the human body. PET stands for positron emission tomography. The machine detects pairs of gamma rays that are emitted indirectly by a tracer (positron-emitting radionuclide), which is placed in the body on a biologically active molecule.
The images are reconstructed by computer analysis. Modern machines often use a CT X-ray scan, which is performed on a patient at the same time in the same machine. PET scans can be used to diagnose a health condition, as well as for finding out how an existing condition is developing. PET scans are often used to see how effective an ongoing treatment is.
A CT or MRI scan can assess the size and shape of the body organs and tissue, but they can't assess function. A positron emission tomography scan (or PET scan) looks at function. An MRI or CT scans tell you what an organ looks like, and a PET scan can tell you how it's working.
Before going through a PET scan, a type of radioactive medicine has to be produced in a machine called a cyclotron. The radioactive medicine is then tagger to a natural...