PET/CT imaging is an imaging technique that combines PET scanning with CT scanning, and is a type of nuclear medicine imaging. Nuclear medicine uses radioactive material to discover and treat diseases such as cancers, heart disease, neurological, endocrine, and gastrointestinal disorders as well as other abnormalities in the body.
The machine itself is large, with a round hole in the middle, similar to CT and MRI machines. Multiple rings of detectors are inside, and record the emission of energy from the radiotracer in the body. A computer helps in creating the images from the data garnered by the nuclear camera.
Nuclear imaging is especially useful because it can so accurately locate molecular activity in the body, being able to diagnose diseases in the earliest stages without being invasive or riddled with pain for the patient (unless there is an intravenous injection required.)
During the exam, the patient is positioned on an examination table, and depending on the type of nuclear medicine, the radiotracer needed will either be injected, swallowed, or inhaled. After about 60 minutes, the radiotracer will accumulate in the area of the body being examined. Then, after they are moved to the PET/CT scanner in order for the imaging to begin, the machine will detect the radiotracer in order to produce pictures and molecular information. The CT exam will be performed first, followed by the PET scan, and the total scanning time will be around 20-30 minutes. In some cases, additional tests involving other tracers or drugs may be used, which can lengthen the procedure time to three hours.
The benefits of a PET/CT scan are extensive, as nuclear medicine has the ability to provide details of the body that other imaging procedures are not. Nuclear medicine is also less expensive than other imaging options and may be able to detect the early onset of disease before it even shows up on other imaging tests.