PET and PET/CT
In July of 2000, Reno Diagnostic Centers introduced PET technology to northern Nevada. By doing so, RDC added an important new dimension to a physician’s ability to diagnose and manage cancer. Now, RDC has added PET/CT to its array of imaging options.
Unlike other imaging technologies that detect changes in the physical size or structure of internal organs, PET detects changes in cellular function. Since these functional changes may take place before physical changes occur, PET may provide earlier diagnosis of disease. PET may also impact the workup of suspected malignancy, provide information regarding staging and treatment and monitor the effectiveness of treatment.
Your physician will be able to tell you precisely what he/she hopes to learn from your PET exam.
How PET Works
The most common form of a PET scan begins with an injection of a glucose-based radiopharmaceutical (FDG), which travels through the body, eventually collecting in the organs and tissues targeted for examination. The patient lies flat on a bed/table that moves incrementally through the PET scanner. The scanner has cameras that detect the gamma rays emitted from the patient, and turns those into electrical signals, which are processed by a computer to generate the medical images. The bed/table moves a few inches again, and the process is repeated.
This produces the digital images, which are assembled by the computer into a 3D image of the patient’s body. If an area more metabolically active, the signals will be stronger there than in surrounding tissue, since more of the radiopharmaceutical (FDG) will be absorbed in those areas.
Because PET scanning often reveals disease much earlier than conventional diagnostic procedures (such as CT or MRI), it can help physicians diagnose disease faster.
Is PET Safe?
The risks associated with a PET scan are very minimal. The quantity of radiation is low and the FDG degrades quickly so that no detectable radioactivity is present after several hours. In addition to the radioactive decomposition, the remaining FDG is eliminated from the body through urine. Family members are not at risk for exposure since greater than 90% of the radioactivity has left the body or decomposed before the patient has left the center.
Is a PET scan painless?
The only pain involved is the needle stick when you receive the radiopharmaceutical, similar to any other type of injection.
How does a PET scan differ from CT or MRI scans?
CT and MRI scans are anatomic imaging modalities, which means they look at the size and shape of organs and body structures. A PET scan is a metabolic imaging modality, which means it looks at function.