Computed Tomography (CAT or CT) Scan

Your doctor has ordered a CT scan. For this study you will either lie on your back or on your stomach and be placed within the scanner opening. The CT scanner opening is very wide and you will not feel confined within the space. When it is scanning it makes very little noise. You will be in the CT scanner for about 20 minutes while the scanning is being performed. During the scanning, it is important for you to hold as still as possible because motion makes the scans blurry.

CT scans use radiation. We try to reduce the exposure of patients to radiation at all times and, if you are pregnant, we would not want to expose you to such radiation unnecessarily. If you are or could be pregnant please let us, the schedulers, and the receptionists know immediately. We will discuss the options with you and your doctor.

If you are not scheduled to have a contrast dye (enhanced) scan, you can eat prior to your study and should take your prescribed medications in a routine fashion.

For Enhanced Scans Only:

For some patients, a small intravenous catheter will be placed in your arm to administer an iodine based contrast agent or "dye". Most patients feel a flushed feeling when the dye does in and some people get nauseated and may even vomit. Other people may have an allergic reaction to the dye, just as some people are allergic to bee stings. The allergic reaction may manifest as hives, asthma, or anaphylaxis. For this reason, you will be asked to sign a consent form before we give you the dye which will describe all the possible things that can possibly go wrong when someone is given contrast agents. Although this risk is small and the benefits of giving you the dye are great, we have created the consent form so that you know all the risks involved before agreeing to have the dye. If you have ever had an allergic reaction to contrast dye, please tell the receptionist when your study is scheduled. We can give you medications up to a day before your study to reduce any! risk to you.

Some patients should not have iodine based contrast dyes. If you have multiple myeloma or diabetes with kidney failure or have kidney failure from other causes, please let us know in advance. We may be able to perform the study without contrast dye or may be able to perform an alternative study. If you are taking Glucophage, an oral drug for diabetes, your drug should be discontinued prior to the study and for 48 hours thereafter.

If you are scheduled to have contrast dye for your study you should not eat for 4 hours prior to the scheduled time of your exam. You should take your medications in their routine schedule except if you are a diabetic and are taking medicines to reduce your blood sugar.

Additional Information

For additional information on the web, we recommend you click on the link below to visit the ACR and RSNA patient information site:

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