Hospitals & Services
About Gastric Emptying Scans ..
Gastric emptying studies are performed to evaluate patients with symptoms that suggest an alteration of gastric emptying and/or motility. They provide a physiologic, noninvasive and quantitative measurement of gastric emptying.
Gastroparesis is the term used to describe non-obstructed causes of delayed gastric emptying. Diabetes mellitus and gastric surgery are the two most common causes of chronic gastroparesis. Other causes include acid-peptic disease, gastritis, chronic pseudo-obstruction either primary or secondary to neuropathies, muscular or connective tissue diseases, epigastric disorders and gastric dysrhythmia. Drugs and hormones may also be responsible for delayed gastric emptying.
Accelerated gastric emptying is usually iatrogenic after gastric surgical procedures such as a vagotomy. After a vagotomy there may be decreased 'receptive relaxation' of the fundus which permits food to more rapidly exit the stomach, despite the decreased motility. Patients with duodenal ulcer, the Zollinger-Ellison syndrome, malabsorption or hypothyroidism may also have rapid gastric emptying. Patients with dumping syndrome show a radid passage of solid and liquid meal into the small bowel, with minimal initial retention in the proximal stomach.
Suspected slow or rapid gastric emptying.
The study is usually performed about 8.30am after an overnight fast.Patients should not smoke or have tea, coffee, caffeine drinks or alcohol for 24 hours prior to the study.
Drugs affecting gastric motility should be stopped 24 -48 hours previously.Gastroprokinetic agents (48 hours), Proton-pump Inhibitors (withhold morning of scan), Opiate Analgesics (48 hours), Anticholinergic, antispasmotic agents (48 hours)
If the patient is diabetic then a blood glucose level needs to be completed before eating.
A standard meal of scrambled egg on toast and milk is given to the patient. The egg is pre-labelled with a technetium colloid and the meal is standardised for fat, carbohydrate, protein and total calorie content.
Immediately after completeing the meal a 2 minute image is taken.
Further images are taken at 30 minutes and 1, 2, 3, 4 hours later.
The patient must remain in the department and not have anything more to eat or drink until the study is complete.
The gastric clearance half-life of the meal is calculated and the % emptying/retention.