Both procedures are considered to be a type of nuclear imaging test, meaning they use a small amount of a radioactive drug (called a tracer) to show differences between healthy and diseased tissue. This substance is typically administered as an intravenous (IV) injection, however, some patients may be asked to inhale it instead. It typically takes 30 to 90 minutes for the substance to travel through your body and be absorbed by the tissue that is being studied and then an additional 30 to 45 minutes for the scan.
Most of the radioactive tracer will leave your body a few hours after your scan once you urinate. However, your doctor may instruct you to drink more fluids to flush it out faster. The remaining traces of the substance will be broken down by your body within a few days.
A radiologist will interpret your exam results and create a report for your doctor who will then discuss the results with you.