Nuclear medicine scans are a valuable tool for medical professionals to diagnose and treat a variety of conditions. These scans use small amounts of radioactive drugs to create images of tissues, bones, and organs inside the body. While there is no direct evidence that the low amount of radiation used in nuclear medicine produces any adverse effects, it is prudent to assume that every exposure to ionizing radiation carries some risk. The amount of radiation exposure from a nuclear medicine scan depends on the type of test and the part of the body being tested.
In general, the amount of radiation from nuclear medicine procedures is similar to that of other radiological procedures and natural background radiation. However, if a procedure offers useful information that is likely to help your doctor decide your treatment, the benefits of nuclear medicine imaging will outweigh your small potential risk. Nuclear medicine scans are especially useful for cancer because they show tumors and track whether they spread within the body. Early diagnosis is often possible with nuclear medicine, since changes in function often occur before changes in the structure.
Nuclear medicine scans can also help doctors find tumors and see how much cancer has spread in the body (called the cancer stage). The steps needed to prepare for a nuclear medicine scan depend on the type of test and the tissue being studied. But if there is any reason to believe that an x-ray, CT scan, or nuclear medicine scan (such as positron emission tomography) is the best way to detect cancer or other diseases, the person will most likely receive more help than the small dose of radiation can harm. However, the doctor will need more focused images (x-rays, CT scans, MRI) of those areas and look for smaller tumors that may not appear on the nuclear scan. At this time, there is no formal mechanism to record and track a patient's cumulative radiation exposure, as is the case with staff.
But it is important to keep in mind that the radioactive material used disappears (breaks down) in a short time.