A SPECT scan works similarly to a PET scan, but it creates images which aren't as detailed. The advantage of this tool is simply that it tends to be cheaper and more available than a PET scan.
While the idea of radiation passing through your body seems dangerous, the procedure is completely safe. However, if you are pregnant, be sure to tell your doctor; you may need another type of scan to limit the radiation exposure. Also, if you are having a scan of your stomach, you may need to fast for 24 hours before the procedure, but usually no other special preparation is necessary.
These nuclear imaging scans are most often used to view blood flow in certain areas of the body. For example, if there is a weak spot in your blood vessel, such as an aneurysm, the PET scan can pick up this abnormal bulge on an artery. This tool is also helpful in determining the cause of poor blood flow to certain organs and identifying a blockage to the gallbladder. Its most promising use seems to be in finding the early reemergence of tumors in patients who have already battled cancer.
"This tool has taken off in the detection of recurrent tumors," says Dr. Robert Zimmerman, the executive vice-chair of radiology at New York-Presbyterian Hospital and Weill Cornell Medical Center, who went on to explain that because PET scans detect active blood flow, it can help specialists distinguish between scar tissue from an old, inactive tumor and a newly-growing one.