A tube oesophagram is a specialised type of imaging scan used when a child is suspected of having a tracheo-oesophageal fistula. Tracheo-oesophageal fistula (TOF) is a rare condition, where part of the oesophagus (gullet or foodpipe) is joined (fistula) to the trachea (windpipe).This information sheet from Great Ormond Street Hospital (GOSH) explains about the tube oesophagram procedure, what it involves and what to expect when your child comes to GOSH to have one.
Often the fistula will not show up clearly on x-rays or other types of scan as it is so small, so a tube oesophagram using contrast – a liquid that shows up well on x-rays – is used.
What happens before the tube oesophagram?
Most tube oesophagrams happen when your child is already an inpatient at GOSH. The doctor will explain the procedure in more detail and discuss any worries you may have.
Many of the studies we perform involve the use of x-rays. If you are pregnant or think you might be, please arrange for another adult to stay with your child during the procedure. This is to protect babies in the womb from receiving unnecessary radiation.
What does it involve?
A tube oesophagram is carried out in the Radiology department, while your child is awake. Before the scan takes place, your child will need to have a naso-gastric tube in place if they do not have one already. This is a thin, plastic tube that is inserted into one of the nostrils, down the back of the throat into the stomach.
They will then need to lie on the scanning bed, usually on their front or side. The doctor will then inject contrast into the naso-gastric tube slowly and gently pull out the tube at the same time as a series of x-rays are taken. If a fistula is present, the contrast is usually seen spilling into the windpipe.
Are there any risks?
If there is a fistula present, a small amount of contrast usually enters the windpipe, which may cause your child to cough but should not affect their lungs. If a larger volume enters the windpipe, this may affect your child’s lungs, in particular, their breathing pattern or heart rate, requiring extra medical support afterwards. Your child will be carefully monitored throughout the procedure to make sure they are safe.
Taking x-rays means using a very small amount of radiation to create the picture. X-rays occur naturally in the atmosphere all around us and everyone receives a small amount as part of everyday life. Each x-ray is calculated so that the best picture can be taken using the minimum amount of radiation.
Are there any alternatives?
Other imaging scans, such as a CT scan or bronchoscopy, can be useful in showing the oesophagus and trachea but they are not usually detailed enough to show a fistula.
A fistula can also be shown by taking x-rays while the child swallows contrast, and the doctor may try this first before performing the oesophagram.
What happens afterwards?
After the procedure has been completed, your child will return to the ward. The radiologists will write a detailed report of the images, which the doctors will use to plan your child’s treatment.