The radionuclides that are employed in a PET scan as part of radiopharmaceuticals work best when used for imaging certain physiological properties. Combined with a CT scan or an MRI, a PET scan is good for locating things such as tumours. As a matter of fact, a PET scan can light up for the brain, the kidneys, and any cancer in the body be it lung cancer, lymphoma, etc., so that doctors can examine and make a diagnosis.
Besides specific targets, the radionuclides can be attached to molecules such as glucose. These molecules would circulate within the human body and metabolize, providing information about activity within the body.
Related: Positron Emission Tomography (PET)
A PET scan can work with any biological active molecule. The most common radionuclide is Fluorine-18. One of the radiopharmaceutical is 2-fluoro-2-deoxy-d-glucose, commonly called fluorodeoxyglucose (FDG). These radiopharmaceuticals are also termed to as radiotracers because they bind to specific receptors or drug action sites within the body. FDG, which is a positron-emitting glucose analog, is well suited for detecting cancers and determining the progress of any treatment of the cancer. Cells, such as brain cells, kidney cells, and cancer cells that need large amounts of glucose, absorb FDG as well. These three types of cells prevent glucose from escaping the cell once absorbed. FDG is missing the 2’hydroxyl, which prevents it from being metabolized within the cell. As a result, the FDG sits in the cell until it decays and emits a positron. FDG PET scans allow for the imaging of the body where there is a high demand for glucose. Not only is it useful in medicine, but also in research, such as within biology and neuroscience.
You can also read: The Process of Setting up a PET scan
