3. GI Tract
Timothy V. Myers, MD
CME offered: No
Article 1. Kevin J. Donohoe1, Alan H. Maurer2, Harvey A. Ziessman3, Jean-Luc C. Urbain4, Henry D. Royal5, and J. Martin-Comin6
Article 2. Patrice K. Rehm, MD
Disclosures: None known
Nuclear medicine evaluation of gastric motility in adults is an extremely useful but often underutilized procedure. The purpose of this article is to make gastric emptying studies user-friendly for patients and radiologists. The review addresses the relevant issues of anatomy and physiology; factors affecting gastric emptying; the radiolabled meal; imaging technique; quantitative analysis; and reporting.
Radionuclide studies of gastric emptying and motility are the most comprehensive and physiologic studies of gastric motor function available. The studies are noninvasive, use a physiologic meal (solids with or without liquids), and are quantitative. Serial testing can determine the effectiveness of therapy. The Society of Nuclear Medicine (SNM) and the American Neurogastroenterological and Motility Society have recently agreed on a standard meal and a standard imaging protocol for measurement of gastric emptying. The recommended meal is intended to simplify and standardize the methodology and reference values based on a large, multiinstitutional investigation of 123 healthy subjects.
This standardization will alleviate the problem of comparing results between institutions that did not use the same meal or imaging protocol. The detailed recommendations for the recommended meal and the imaging protocol can be found in the paper by Abell et al. listed in the bibliography of this guideline.
Keywords: nuclear medicine, stomach, gastric emptying, gastroparesis, gastric motility
There are 2 reference articles.
Gastric emptying is not a common procedure even in many busy nuclear medicine departments. Each department, has its own protocol for imaging these patients. Radiologists, frequently have to consult text works or journals for the specifics of how to read them. These 2 articles offer specific information on a background, definition and other information required to do these procedures. Also included, is information on how to interpret the findings once obtained.
Gastric emptying examinations are performed with solid meal preparation typically using egg whites or a substitute and other materials mixed with up to 1 mCi of technetium 99m sulfur colloid. Images are obtained over a specific sequence for delayed period of time up to 4 hours depending upon the protocol used by the imaging department. The time delayed information is displayed both as images and as a curve of radioactivity versus time. Figure 1, is an example of the Format which can be used by the nuclear medicine technologist to display this information.
Cheat Sheet values:
Gastric emptying normal percentage values:
30 minutes: <70% of retention (> 30% emptying) suggests abnormally fast emptying.
60 minutes: <90% retention (>10% emptying) is normal; less than 30% retention (>70% emptying) suggests abnormally rapid emptying.
90 minutes: <65% retention (> 35% emptying) is normal.
120 minutes: <60% retention (> 40% emptying) is normal.
180 minutes: <30% retention (> 70% emptying) is normal.
Gastric emptying T-1/2:
Solid: The normal range is 60-105 minutes
Liquid only: Normal range is 10-45 minutes.
Liquid only-children: At 60 minutes, normal range is 44-58 % .
Liquid only-infants: At 60 minutes, normal range is 32-64 %.
Gastric Emptying Scintigraphy http://bit.ly/ncpVfA
Article (1-5): 4/5
1. Reads poorly and difficult to understand 2. Adequate, could have been better. 3. Average readability 4. Understandable and adequately readable. 5. Readable and interesting with information presented very well.
Images (1-5): 2/5 mainly charts
1. Not enough images, images not well done 2. The images could have been better or more of them 3. Average images and image number 4. The images were good and there were a reasonable number of images 5. Excellent images demonstrating the areas of interest presented in the article.
Overall (1-5): 4/5
1. Not recommended 2. Recommended somewhat 3. Average article, read if of specific interest 4. Recommended article 5. Absolutely recommended.