50 children with a strong clinical suspicion of gastroesophageal reflux and 10 control patients were evaluated with gastroesophageal scintiscans. 500 muCi à 1 mCi of Tc sulfur colloid mixed the patients' routine milk or formula feeding was administered and serial images of the abdomen and thorax were obtained. A positive scintiscan was found in 35 patients (sensitivity 70%) and none of the controls (specificity 100%). A comparison of findings in 34 patients referred for both radiographic and radionuclide studies showed that barium studies were positive in 38% and radionuclide in 64.7%. We found this examination to be more sensitive that the standard barium radiography particularly in patients with respiratory symptoms. We concluded that the GE scintiscan is complementary to barium studies in the diagnosis of GE reflux. Pulmonary aspiration of gastric contents was detected in only a case of the 35 patients with documented GE reflux. A T 1/2 emptying gastric longer than 90 minutes (linear calculation) or 105 minutes (exponential calculation) is an indirect GE reflux test. This procedure is simple, safe more physiologic than other available examinations.