Computed Tomography is a safe, simple and painless special type of X-ray. The scanner itself looks like a large doughnut with a narrow table. As the X-ray tube rotates around a specific area of the body it takes pictures from different angles. Because it is more sensitive than conventional X-ray and the computer technology creates much clearer pictures, it allows your doctor to look at an extraordinarily precise image of the inside of your body and diagnose certain problems earlier and with more accuracy.
Certain examinations will require more or different instructions as recommended by your doctor. This is meant to be a general guideline only, and each patient should always follow the directions of his/her personal physician.
- If you are having a body CT scan, you may be asked to drink only clear liquids and abstain from solid foods or refrain from eating or drinking for a period of time before the exam. Other scans may require you to drink a quart of liquid prior to the scan. For other exams, a contrast may be injected into a vein during the scan. If you are scheduled to have a test with intravenous contrast you should not eat for four hours before the exam. You should, however, take all your medications with a sip of water at the regular time(s).
- It is very important to let your doctor know if you have had any previous allergic reactions to a contrast medium, iodine or shellfish, or if you have asthma. If you have diabetes or take medications, please inform the medical staff that will be performing the exam.
- If you are a diabetic, hold Metformin medication (Ap Metformin, Glucophage, Glucophage XR, Glucovance, Glycon, NovoMetrformin) the day of your procedure and 48 hours after your procedure.
- If you are or could be pregnant, you should tell your doctor before having any type of CT scan.
- For head and neck examinations, you will be asked to remove all jewelry, hairpins, eyeglasses, hearing aids and dentures or you can leave them at home.
- Wear comfortable, loose-fitting clothes.
You will lie on a comfortable table (usually on your back). The table will slowly move you through the opening of the unit. All you need to do is listen to the instructions of the medical personnel. During the exam you will feel the table you are laying on move slightly and you will hear only a low whirring noise. Typically, only patients having full body scans will be asked to change into a hospital gown for the exam. It is always important, during any test, to let the staff know immediately if you feel any discomfort. After the exam, a report will be sent to your doctor who will discuss the results with you.
Even though the images are produced in a few seconds, you can expect the test to last approximately 15 – 30 minutes, based on the part(s) of the body being scanned. If a contrast medium is used, it may take longer.