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What is a CT Colonography scan?
Your doctor or surgeon has referred you for CT Colonography (CTC) because they would like to examine the colon (large bowel) for polyps or cancerous growths. CT scans are performed following the inflation of the large bowel with gas. CTC is often performed if a patient is not suitable for a colonoscopy or if a colonoscopy was not able to fully visualise the large bowel.
How long will the procedure take?
The CTC scan takes approximately 30 minutes. Please allow time to register at Reception and fill in some paperwork. You may be requested to wait after the procedure so our staff can be sure that you are ready to be discharged home. In total, you may be in our centre for up to 2 hours.
Is there any special preparation?
At the time of your booking, please inform the staff before the procedure if you have any allergies or are pregnant.
Please list or bring all of your prescribed medications, those medications that you buy over the counter, including herbal remedies and supplements.
Special preparation is required. At the time of booking, our staff will provide you with written preparation instructions involving a thorough bowel preparation and a Low Residue Diet similar to that used for a colonoscopy.
If these preparation guidelines are not adhered to, or if the preparation has not worked sufficiently, we may need to re-book the CTC as the images will be technically degraded and non-diagnostic.
It is recommended that you wear comfortable clothes as you may feel bloated afterwards. You will be asked to change into a gown for the procedure.
You may need someone to drive you home after the procedure if you are given an injection of Buscopan, as this medicine may cause short-term blurred vision. You should not drive until any blurring of your vision has returned to normal.
What do I need to bring with me?
On the day of your appointment, please ensure you bring
- Your request (if you have it)
- All previous relevant scans or X-rays
- Medicare and healthcare cards (e.g. DVA or healthcare concession card)
- List of all medications
What happens during the procedure?
Prior to the CT scan, our clinical staff (radiologist, radiographer or nurse) will discuss the examination with you, including the need for the administration of contrast or medications during the CT scan and any risks specific to you. You will be provided with the opportunity to ask questions, and you will be given a consent form with more detailed information to read and sign.
An initial scan or X-ray may be performed to make sure that your bowel is clear enough to do the CTC. It is very important that your bowel is clear in order to get the information that our doctor needs to make a diagnosis. Please tell us if you think that the bowel preparation hasn't worked very well.
You will be asked to change into a gown. You will be brought to the CT room where you will lie on the CT table. You may be given an injection of medication called Buscopan to reduce any spasming of the bowel. This injection can be accompanied by a short period of blurred vision or a dry mouth.
A small, flexible tube will be passed into your rectum (back passage), and a small balloon will be inflated to hold it in position. Gas (either room air or carbon dioxide) will be gently introduced into your large bowel. The purpose of the gas is to inflate the large bowel as much as possible to eliminate any folds or wrinkles that might obscure the inside of your large bowel. This will be done by one of our clinical staff -a radiologist, radiographer or nurse.When the bowel is distended, it is common to experience bloating and wind-like cramping pain.
You will be asked to roll into different positions for the CT scans. The CT table will move in and out of the scanner multiple times and give you breathing instructions before each scan. It is important you take the same sized breath each time.
Once the scan is complete, the tube will be removed, and you will be able to dress and visit the bathroom if required. Our staff will confirm that you are feeling OK before you leave.
Are there any after effects from the procedure?
Due to the bowel preparation, you may feel a little light-headed or weak; once you resume your regular diet this feeling should resolve.
If you have been given an injection of Buscopan, you may experience a short period of blurred vision. Our staff will monitor you closely after the scan to ensure that it is safe for you to leave our imaging centre. You should not drive until any blurring of your vision has returned to normal.
What happens after the procedure?
Once all the CT scans have been taken (around 20 minutes), you will be allowed to dress and visit the bathroom.The gas will dissipate and it is usual to experience some mild bloating and abdominal cramping for a couple of hours after the examination. If you experience severe or worsening abdominal pain in the hours following the examination it is important to contact your doctor, the Lumus Imaging centre or attend your nearest Emergency Department.
Our staff will provide you with clear written instructions on how to look after yourself following the CTC.
What are the benefits?
CT Colonography is a safe way of examining the large bowel without requiring a hospital admission or sedation/anaesthetic.
Are there any risks?
In referring you for this scan, your doctor is of the opinion that the benefit of this procedure for you are greater than the risks. There are some risks and complications associated with a CTC. There is occasionally a small amount of bleeding (mostly due to the bowel preparation) and a very small risk of a perforation (or a small tear) in the bowel wall. If you experience severe or worsening abdominal pain, you should attend your nearest Emergency Department.
CT uses ionising radiation to produce the images. The radiation doses associated with performing a CT scan of your large bowel, CT Colonography, are kept as low as possible by the CT radiographer and the associated risks are low.
If our staff will be giving you iodinated contrast or a medication called Buscopan, they will ask you more detailed questions before doing so.
Before the CTC scan, the radiologist (or delegate), will discuss the procedure with you in detail, including any risks specific to you. You will be provided with the opportunity to ask questions.
When do I get the results?
Our specialist doctor, the radiologist, who interprets the images will send a report outlining the procedure to your referring doctor/surgeon and your regular GP. It is important that you make a follow-up appointment with your referring doctor/surgeon to discuss your results.
I still have questions, who can I ask?
Medical information can be complex, and you may receive information that you do not fully understand. It is important for you to consider the risks and outcomes of the procedure as well as your personal needs before making a decision to undergo the procedure.
If you have read this information and are still unsure if this is the correct procedure for you; before making a booking, you should discuss your questions or concerns with your referring doctor in the first instance. Your regular GP and/or your family may also be a useful resource. Your referring doctor can answer questions about the risks and benefits of not having the procedure and other options for treatment.
If you have questions before your appointment about what is involved on the day, our staff would be happyto assist. Please contact the imaging centre where you have made your appointment.