Information about CT Scans
Is a CT scan painful?
No, CT is quick and painless – you won’t feel anything. If intravenous contrast is used you will require a small needle inserted into your arm or back of hand for the injection.
Preparation for your CT scan
The radiology company will send you details of preparation for a CT scan; please check with them about their requirements. As a guide, in urology, we principally use three types of CT:
- CT KUB – this is a plain CT without intravenous contrast and is used for urinary/kidney stone problems. You do not need special preparation for this kind of CT, although it is helpful to have a full bladder so try not to urinate for at least one hour before the scan.
- CT Urogram – this kind of CT takes three images of your body all in quick succession. One is a plain CT, the second is a CT after injection of intravenous contrast (a few minutes after injection), and a third CT is taken a few minutes afterwards (delayed phase). You will need contrast injected for this, and you may need some simple preparation such as not eating for four hours, and ensuring you are well hydrated. The radiology company will give you instructions well before your CT.
- CT for staging for urology cancer – this kind of CT uses intravenous contrast and you may need special preparation. As a guide, do not eat for 2 to 4 hours before. The radiology company will tell you what to do well before your scan.
Important things to tell the Radiographer before your CT
You must tell the radiographer if:
- you could be pregnant
- you are taking diabetic medication
- you have had a diagnosis of kidney disease
- you have ever had a reaction to intravenous contrast
What happens during a CT scan?
You will lie on a special couch, which moves into the scanner. It is not a claustrophobic feeling. Nothing touches you, and there is no discomfort. Inside the scanner is an X-ray tube, which moves around you, while detectors capture the X-rays. CT scans only take minutes in most cases. If you have had an injection of intravenous contrast you will be monitored for 15 minutes to half an hour afterwards.
How long does it take to get the results?
The scan needs to be viewed and interpreted by a Radiologist, and this is quite an involved process. Usually, the results are back with 24 to 48 hours. With the simple scans (such as CT KUB), the results are often available very soon.
Are there any risks of a CT scan?
Yes there are some small risks, but these can be minimised:
- Make sure you tell the radiographer or radiologist if you are, or you could be, pregnant. If you are pregnant, the risks of radiation to the foetus need to be carefully weighed up with the risks to you of not having a CT scan.
- Allergic/anaphylactic reaction to intravenous contrast is very rare, but can be serious. It is very important that you tell the radiographer if you have ever had an allergic reaction to this.
- You must tell the radiographer if you are taking diabetic medication. One medication, metformin, can cause problems with your kidneys if you are given intravenous contrast.
- You must tell the radiographer if you have ever had a diagnosis of kidney problems (chronic kidney disease / kidney failure). This is only of relevance of you are having intravenous contrast.
- There is a small dose of radiation from a CT scan. The amount depends on the type of scan. One or a few scans are unlikely to cause any problems, but if you have frequent scans, the dose of radiation can add up and may be a concern. As a general guide, the CT scans we use in urology give you a radiation dose equivalent to the amount of background radiation we are all exposed to in 1 or 2 years.
If you have any questions, please contact your chosen Radiology provider. The administration staff at East West Urology do NOT have information about your appointment times for radiology, and are not able to give medical advice or answer questions about radiological investigations. The staff are not able to give you your results – these need to be given to you either by the radiographer or by Nick Brook. Use the links below for contact details for the radiology companies in South Australia:
Radiology SA http://www.radiologysa.com.au
Benson Radiology http://bensonradiology.com.au
Dr Jones & Partners http://www.drjones.com.au
Disclaimer
This information is intended as an educational guide only, and is here to help you as an additional source of information, along with a consultation from your urologist. The information does not apply to all patients.
Not all potential complications are listed, and you must talk to your urologist about the complications specific to your situation.
