Upcoming gastric emptying scan?

The patient will eat food ( possibly an egg salad sandwich or a combination of solid and liquids),which has been labelled with a radioisotope) The abdomen is then imaged under a gamma camera for a short time at a number of equally spaced time intervals. The total time in the imaging department will depend upon the rate of stomach emptying. If it empties rapidly then the total study time may be as short as 1 hour. If it empties more slowly, the study takes longer. The emptying time is based on how long it takes for the initial activity to decrease to one-half of the initial value. A graph is created plotting activity against time.