The Addition of Liquid Gastric Emptying to a Solid Gastric Emptying Study Increases Detection of Gastroparesis

Purpose: Standard teaching is that only solid gastric emptying scintigraphy is needed to diagnose gastroparesis because liquid emptying is less sensitive and often normal until the disorder is advanced. However, we have seen numerous patients with prolonged liquid but normal solid emptying. The purpose of this investigation was to determine if liquid gastric emptying has added diagnostic value when obtained in addition to solid emptying for detection of gastroparesis. Methods: Sixty consecutive patients (age 18–65, 39 male, 21 female) referred for suspected gastroparesis had sequential clear liquid and solid gastric emptying scintigraphic studies the same morning. Three were diabetics, 8 had GER, none had prior gastric surgery. They were on medications as prescribed by the referring physician, although none were known to affect emptying. The patients initially ingested 300 ml water with 0.2 mCi In-111 DTPA and 1 minute gamma camera images were acquired for 30 minutes. They then ingested a standardized egg substitute meal (Tougas et al.) labeled with Tc-99m sulfur colloid, 2 mCi, and images were acquired at 0, 1, 2, 3, and 4 hours. A half-time of emptying was quantified for the liquid studies (Chaudhuri et al) and the percent emptying at each time interval for the solid studies (Tougas et al.). The results of the two studies were analyzed. Results: Both solid and liquid emptying studies were normal in 50% of patients. Both studies were delayed in 10%. The solid study showed delayed emptying in 23% of patients. The liquid study was delayed in 33%. Solid emptying was delayed and liquid was normal in 13%. Solid emptying was normal but liquid emptying was abnormal in 27%. Of those patients with normal solid emptying, 31% had delayed liquid emptying. The addition of patients with delayed liquid emptying to those with delayed solid increased the rate of gastroparesis detection from 23% to 40%. Conclusion: The addition of liquid to solid gastric emptying scintigraphy increased the detection rate of gastroparesis compared to the solid emptying study alone. Both studies should be performed routinely to maximize sensitivity for detection of gastroparesis.