Nuclear medicine scans are performed using small amounts of radiotracers (radioactive material sometimes referred to as radiopharmaceuticals) that are injected, ingested or inhaled into the body. Different radiotracers are used depending on the body part being targeted. A camera highly sensitive to radiation is then used to measure the radiation given off. The resulting images demonstrate structure and especially function. Because areas of high metabolic activity will accumulate a greater amount of radiotracer, these areas will be "hot". "Cold" areas indicate less activity. Nuclear medicine exams can demonstrate the movement of blood flow, the time it takes for food to pass out of the stomach, or the amount of bile moving out of the gallbladder.
What to Expect
You will be given a dose of radiotracer. Depending on your specific procedure, it may be injected into a vein with a needle, swallowed in a capsule, eaten mixed with food, or inhaled as a gas. It can take anywhere from several seconds to several days for the radiotracer to accumulate in the organ being studied, depending on the specific exam. Thus you may be imaged immediately, be asked to return in several hours, or even a day later. The images will be captured by a gamma camera that will be positioned near you as you lie on a table or sit in a chair. Most Nuclear Medicine exams will take approximately one hour to image. For best results please follow your technologist's instructions regarding position and hold as still as possible while the images are being made.
The Nuclear Medicine technologist will take a series of images appropriate to the body part being examined. You may be asked to wait while your technologist reviews the images with the radiologist to ensure no extra views are needed before releasing you. In some cases, the radiologist may order extra views to clarify the results of your exam. The Radiologist will interpret the images and dictate a report that with be typed and sent to the doctor that ordered the exam for you.
The radiotracer will decay naturally and be gone from your body in a few days.