Egg labeling methods for gastric emptying scintigraphy are not equivalent in producing a stable solid meal

Abstract

A wide range of radiolabeled test meals have been used for gastric emptying scintigraphy. The purpose of this study was to test whether 99mTc-sulfur colloid-labeled liquid egg white is as stable as 2 fresh whole eggs labeled with 99mTc-sulfur colloid and whether the cooking method is important. Methods: Whole eggs and liquid egg white were mixed with 99mTc-sulfur colloid and cooked by either microwaving or frying on a griddle. The cooked eggs were tested for breakdown after 2 and 4 h of incubation in gastric fluid or HCl. Results: Labeled liquid egg white, prepared by either method of cooking, exhibited less breakdown in gastric fluid than whole eggs. Whole eggs cooked in the microwave exhibited significantly more breakdown than liquid egg white. Conclusion: 99mTc-Sulfur colloid binds better to egg whites compared with whole eggs. These results emphasize the need to evaluate the stability of new radiolabeled test meal preparations, including the method of cooking. Copyright © 2007 by the Society of Nuclear Medicine, Inc.