CT - Patient Information
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CT is used to look at internal organs and structures of the body to identify disease processes such infection, cancer, traumatic injury or abnormal anatomy. It is useful in detecting cancer in different organs of the body such as lung and liver. With CT scanning a doctor is able to confirm whether a tumour is present, the size of the tumour, its exact location and whether the tumour is involving nearby tissue. CT is helpful in the planning of various medical procedures such as biopsies, surgery and radiation treatment. CT is useful in trauma as it can quickly help identify injury to internal organs such as the brain. CT may also be used to measure bone mineral density.
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The doctor may advise you to not to eat or drink anything up to one or more hours before the procedure.
In CT scanning contrast materials maybe used to make tissues more visible from one and other. Depending on the part of the body to be scanned, you may be asked to drink a contrast fluid, or have a dye injected into your blood or have an enema (An enema is where fluid is introduced into the rectum through a tube passed into the anus). Before any contrast material is used you will be asked whether you know if you have any allergies especially to contrast material or iodine.
Before the scan you may be asked to where a hospital gown and remove any metallic objects such as jewelry and glasses.
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The technician will bring you into the room and position you on the CT scanner table. It is important that you are comfortable as you have to remain still during the scan. As the scan proceeds the table will move through the doughnut shaped scanner. Depending on the part of the body being scanned you may be asked to hold your breath for a short period of time. The radiologist will be able to communicate with you and see you, although you will be alone in the room. S/he may give you additional instructions during the scan.
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Depending on the type of scan you are having it may take from 10 minutes to ½ an hour. If CT is being used to guide a procedure such as a biopsy the procedure will take longer.
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The CT scan does not cause any pain. You will just hearing the clicking and whirring noises of the machinery. If you are asked to drink a contrast material before the scan you may find this tastes slightly unpleasant. If you have an enema before the scan you may feel a sense of abdominal fullness, although this will not last long. Allergic reactions to the contrast material are very rare, but if you feel that you are having symptoms let the radiologist know.
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CT involves exposure to radiation in the form of x-rays. CT scans are performed in such a way as to keep the amount of exposure to radiation to a minimum. We are constantly exposed to very low levels of radiation from natural sources in our daily lives. This radiation is known as background radiation and the average radiation dose from one CT scan is the same as a person receives from background radiation in 3 years. The benefit of the CT scan far outweighs any risk from radiation exposure. If you have frequent scans you may wish to keep a diary for your records and inform the radiologist who will advise you of your exposure risk.
Women should inform the radiologist before the scan if there is any possibility that they are pregnant, in order to protect the foetus form exposure to radiation.
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After the scan once the radiologist is happy that he has collected enough information you are free to go back without any restrictions.
The radiologist will interpret the results and send a report to your doctor. Your doctor will explain the results to you and tell you what the significance is for you.
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