Nuclear medicine uses a "tracer" to create pictures that help doctors see how various parts of the body are functioning. Depending on the procedure, patients either drink a special liquid or are given a "poke" before their exam so that contrast, or dye, can be injected. Contrast helps highlight the part of the body that the doctor wants to see better. Then, we wait for the "tracer" from the liquid or the poke to reach the area of the body we are examining. This can take any where from 15 minutes to four hours. If the wait will be long, you and your child are free to leave the Clinic and return at an appointed time. Once the "tracer" is in place, the child lays still on a scanner while the images are captured.