Computed Tomography (CT) Scan
A CT scan is a special type of scan that uses X-rays to take pictures of slices of organs and structures in the body. A computer then processes these pictures to build a 3D picture of the body. A CT scan offers fantastic pictures of organs including the liver, pancreas, spleen, bones, soft tissue and blood vessels. CT scans are commonly performed on the head, chest and abdomen and patients lie on a couch which slides through a narrow “doughnut” as the images are obtained.
A CT scan offers a more detailed image that that of a plain x-ray and allows quick, accurate diagnosis of a number of medical and surgical conditions.
Patients are encouraged not to eat anything for up to four hours prior to the scan however, they can drink water. Strenuous exercise and caffeine should be avoided on the day of the scan and it is advisable to arrive in plenty of time in order to allow the heart to rest. Most scans take approximately 30 minutes but occasionally a scan of the abdomen can take up to one hour. The procedure is painless.
During the scan patients are asked to lie very still on the CT table, and for certain scans patients will be given an injection or drink of contrast agent (a radio-opaque dye) which allows the radiologist to see parts of the body more clearly. Scans of the chest, abdomen or pelvis requiring the injection of contrast will take longer than non-contrast scans. If a patient is pregnant or there is or possibility of being pregnant, the radiographer should be informed prior to the scan.
Patients should continue to take their current medication unless they are advised otherwise, and patients with diabetes should inform the Radiology Department prior to a scan which medication they are taking.
Possible Side Effects
The injection can make some patients feel hot and give them a strange taste in the back of the throat. This is quite normal and quickly passes. Occasionally other side effects such as feeling sick, skin reactions and very rarely anaphylaxis can occur. For this reason, patients are asked to stay in the department for 15 minutes after their scan to observe for this. If delayed reactions develop after leaving the hospital, then patients should seek medical attention.