Normal values and symptom correlation of a simplified oatmeal-based gastric emptying study in the Chinese population

Background and AimInstant oatmeal has been proposed as a good alternative to the standardized low-fat egg white test meal for gastric emptying studies. We aim to establish normal values of oatmeal-based gastric emptying scintigraphy and test its correlation with gastroparesis symptoms in the Chinese population. MethodsThis study prospectively enrolled 60 healthy volunteers, 30 functional dyspepsia and 30 diabetes patients with gastroparesis symptoms. All participants were evaluated using the Gastroparesis Cardinal Symptom Index. Each participant ingested instant oatmeal mixed with 1 mCi of Tc-99m diethylenetriaminepentacetic acid, and serial imaging was immediately acquired for 3h in the supine position using a left anterior oblique projection. Time-activity curves were generated and quantitative parameters were determined. Normal values were established from healthy volunteers and further applied in the symptomatic patients. ResultsAll participants finished the test meal and tolerated the procedure well. All gastric emptying parameters were not significantly affected by age or gender. Values above the 95th percentile of T-1/2, gastric retention at 1, 2, and 3 h (85 min, 65%, 28%, and 8%, respectively) were indicative of delayed gastric emptying. Values below the 5th percentile of gastric retention at 0.5 and 1h (40% and 15%, respectively) were indicative of rapid gastric emptying. The lower gastric retention limit at 0.5 and 1h were 40% and 15%, respectively. Four (13.3%) diabetes and four (13.3%) functional dyspepsia patients had delayed emptying while three diabetes patients (10%) had rapid emptying. Gastric emptying parameters correlated best with vomiting (r=0.621) and nausea (r=0.566) in diabetes patients. ConclusionsWe established normal values of oatmeal-based gastric emptying scintigraphy and observed good correlation with cardinal gastroparesis symptoms in the Chinese population.