Gastric emptying study Factsheet
Introduction
A gastric emptying study checks how fast food or liquid moves from your child’s stomach to their small intestines. The small intestine breaks down food from the stomach and absorbs nutrients and water.
The gastric emptying study uses:
- a Gamma camera – a large camera that measures radiation
- radiotracer- a small amount of radioactive fluid that moves through the body.
The gamma camera takes pictures of the radiotracer moving through your child’s digestive system. The digestive system is the group of organs that break down food, absorb nutrients and remove waste.
A gastric emptying study is used to check conditions like:
- gastric dysmotility- a range of disorders where the stomach has trouble moving food properly, causing digestion issues
- gastroparesis- a condition where the stomach muscles don’t work properly, causing digestion issues
- unexplained nausea and vomiting.
Before the scan
Your child’s treatment team will give you instructions on how to prepare for the scan.
Your child must stop eating and drinking for 4 hours before the scan. This is called fasting nil by mouth, and it means no solid food or fluids, including breast milk and infant formula.
Let your child’s treatment team know if your child:
- is gluten intolerant
- has an egg or other food allergy
- has any other allergies.
Talk to your child's doctor if you have any concerns or questions.
During the scan
The scan will take between three and four hours. You can stay with your child the whole time.
Your child will not feel anything during the scan, and the camera will not touch them.
There are two types of gastric emptying study.
Solid gastric emptying study
Your child will eat a meal with the radiotracer added to it. For solid foods, your child will be asked to eat:
- 2 slices of bread
- strawberry jam
- 2 cooked egg whites
- a drink of water.
Most patients choose to eat the slices of bread, strawberry jam and cooked egg whites together as a sandwich.
The radiotracer will not change the taste or texture of the food.
Liquid gastric emptying study
Your child will have liquids with the radiotracer added to it.
Children will be given a small amount of milk mixed with radiotracer if they:
- are under five years old
- are bottle-fed
- have a nasogastric (ng) tube
- have a percutaneous endoscopic gastrostomy (peg) tube.
Children over five who can drink liquids as normal will be given a flavoured milkshake with radiotracer mixed into it. The milkshake is called Ensure. Ensure comes in different flavours, including:
- mixed berries
- banana
- vanilla
- chocolate.
The flavour will depend on what is available at the time of the scan. The radiotracer will not change the taste or texture of the milkshake.
The scan
Your child will eat a meal or drink a liquid with radiotracer added to it. The scan will start as soon as your child finishes eating or drinking before the stomach empties.
Scans will take place:
- continuously for the first hour
- two hours after the start
- four hours after the start.
Generally, the steps are:
- your child lies on the scanning bed
- velcro straps may be used to gently help your child stay still
- over one hour, the camera takes images of the food or liquid moving from the stomach to the small intestine
- delayed images are taken at two hours and four hours after the meal. These images will take less than five minutes each.
Your child cannot eat or drink anything until the scan has finished.
After the scan
You can leave once the results are checked by a doctor or nuclear medicine scientist.
The results will be sent to your child’s doctor within a couple of days. You will need to schedule a follow-up appointment with your child’s doctor to discuss the results.
Management
Radiation
Your child will be exposed to a small amount of radiation during the scan. The benefits of finding and treating kidney problems are greater than the small risk of this low dose.
Allergic reactions
Allergic reactions to radiotracer are very rare and usually mild. Your child’s doctor will talk to you about any potential risks before the scan. Let your child’s treatment team know if they have any allergies.
Supporting your child during the scan
Scans can be uncomfortable for children. You can prepare your child by:
- explaining to them why the test is needed in simple words
- bringing along their favourite comfort objects, like a blanket, toy, or dummy
- asking the treatment team about support from Child Life Therapy services.
