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Computed Tomography (CT) Scan

If your doctor has ordered a CT examination, you'll find answers to commonly asked questions below.

What is a CT?

CT stands for computed tomography. This technique uses xrays to make images of your body in a cross sectional way. A CT image typically is thought of as a slice and allows the radiologist to look inside the body. CT shows healthy and diseased tissues inside the head, neck, chest, abdomen, pelvis and extremities.

How does a CT scan work?

You will lie on a skinny table called the gantry and be slid inside the CT scanner which looks like a large ring. While you remain still, the xray emitter and detectors are spun around you gathering the information used by the computer to make the slice images. The images are then printed on a sheet of film and the radiologist reviews them.

Are there special instructions I should follow before the CT scan?

The answer is Yes. Many CT scans require the use of contrast agents to make parts of the body show up on a CT scan. For most scans of the abdomen and pelvis, you will drink a contrast agent that will allow your stomach and intestines to show up. For scans of the neck, chest, abdomen and pelvis, an intravenous contrast agent is injected. This contrast agent contains iodine. The technologist will ask you specific questions to find out if you have an iodine allergy. The radiology department will contact you with specific instructions before your scan is scheduled.

Does having a CT scan hurt?

There is no pain involved in having a CT scan.

How does a CT scan help me?

CT scans allow radiologists to look at the inside of your body. Usually, these scans help reassure you and your doctor that everything is normal. Sometimes a CT scan will reveal a finding that allows your doctor to treat a disease early and this can save you valuable time. CT is often used to monitor the effectiveness of different treatments for patients with cancer.

When do I learn of the results?

If there is a very worrisome finding on the scan, the radiologist will inform you and your doctor right away. For most scans, it takes from three to five days for the radiologist's report to make it to your doctor. Usually, your doctor will discuss the results of the study and make plans for treating any symptoms you may be experiencing .

How long does a CT scan take to complete?

The time it takes to complete the scan is generally only a few minutes. There is a considerable amount of "set up" time needed for each scan. On average, plan on spending at least one half hour in the CT room and possibly longer. The radiology department will contact you with specific times for your appointment.

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