Use of ⁹⁹Tc(m) DTPA for measuring gastric emptying time

A rapid and easy isotopic method for measuring gastric emptying time (GET) is described. It involves the use of (99m)Tc diethylenetriamine pentaacetic acid (DTPA) and a gamma camera with a computer. Results of animal experiments and 24 studies in 8 normal volunteers are presented. The radiopharmaceutical is neither absorbed from nor absorbed to the stomach in any significant amount. The experimental data show less than 1% absorption and less than 1% adsorption of the compound in 30 min. The mean gastric emptying T(1/2) for a liquid meal in normal subjects was found to be 12 ± 3 min. Since (99m)Tc DTPA fulfills the criteria as an ideal agent for measuring GET and the technique is noninvasive with reproducible results, it may have a potential clinical use.