Computerized Axial Tomography (CT or CAT) Scan for Radiation Treatment Planning
A CT scan is a type of x-ray. A CT scan done in Radiation Oncology is used for treatment planning. This type of CT is looked at only by persons within the department. This type of scan is not used to diagnose disease.
You may need intravenous (IV) contrast for the CT scan. If you have an allergy to IV contrast or dye, iodine, or shellfish tell the nurse or therapist when you arrive. IV contrast is a clear liquid injected into an IV during the scan. As it goes through your blood stream, it highlights your blood vessels and body organs. Some patients getting IV contrast, may feel warm or have a strange taste in their mouth. These are normal side effects that only last for a few seconds.
On the day of your scan,register in the Town Square, near the hospital/clinic entrances. Then take the K or WIMR elevator down to the basement. Follow the signs to check in at the Radiation Oncology Reception desk.
Your CT scan for radiation treatment planning has been scheduled as follows:
Before the Scan
Your health record will be reviewed. We will ask you about your prior scans, allergies and medicines. We may need to get a creatinine blood test. This test shows how well your kidneys are working. If you need this test, it will need to be done before the CT scan. Do not eat or drink anything for 4 hours before your scan. You may take your medicines with a sip of water.
If you are pregnant, or think you might be pregnant, tell us before the scan is done. Your doctor may order a pregnancy test if you are of childbearing age. Nursing mothers should not breast-feed for 24 hours after getting IV contrast. They should also pump and discard their breast milk for 24 hours.
Let us know if being in confined spaces is difficult for you. We can give you medicine to help you relax. If you take this type of medicine for the scan, you will need someone to drive you home. You should not drive or use dangerous equipment for 24 hours.
If you take a medicine called metformin (Glucophage®, Glucovance®,Metaglip®, Avandamet®) you should not take it on the day of your scan. You should also not take metformin for 48 hours after IV contrast is given. Metformin can react with the contrast and increase the risk of damage to your kidneys. Tell us if you take this medicine.
Tell us if you take insulin. If your CT scan is scheduled early in the morning, you may need to take a smaller dose of insulin. If your scan is in the late morning or early afternoon, you may be able to eat early and take your normal insulin dose. We can check your blood sugar when you are in the department. We have juice, soda and crackers for you if you need them.
If you are to get IV contrast for your scan, a nurse will put a small IV into your arm or hand. Wear clothing with loose sleeves. In most cases a PICC line or Port-a-Cath cannot be used for IV contrast. This is because the contrast is injected quickly, under high pressure. The high pressure can damage the device. Some ports (Power Ports) can be used for IV contrast.
We may ask you to remove some of your clothing for the scan. Clothing that contains metal (jeans, under wire bras) may also need to be removed. You will be given a hospital gown, robe, towel, and/or blanket to use.
During the Scan
You will lie on a narrow table. The table will move in and out of the opening in the scanner. It takes about 30-60 minutes to complete the scan. A lot of this time is used for getting you into the right position.
The scan itself takes only a few minutes. During the scan, you will be alone in the room. We will be able to see you through a window. We will be able to hear you through a speaker. You will need to lie quietly during the scan. You may be asked to “take a deep breath and hold” during part of the scan. In most cases there is no pain or discomfort during the scan. If you need something, or have any problems during the scan, just speak up as we will be listening for any concerns.
After the Scan
Your IV will be taken out. You will need to drink 2 quarts of fluids (no caffeine) over the next 24 hours. These fluids will flush the contrast out of your body. If you have problems taking fluids please let us know.
The images from your scan will be reviewed by the doctors and physics staff. Together they will plan your radiation treatments. This will take a few days. You will get a call telling you of the date and time when treatments will start. On your first treatment day, plan to arrive 15 minutes early. You will be told which treatment machine to go to.
Questions or Concerns
Please call if you have any questions or concerns. The phone number for the Radiation Oncology Clinic is (608) 263-8500. If you live outside of the Madison area, call1-800-323-8942. If the clinic is closed, your call will be transferred to our answering service. Ask to speak to the radiation doctor on call. The doctor will call you back.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 01/17/2013
Copyright © 01/17/2013 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#6092
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