CT, Cardiac Scoring, Lung Cancer Screening - Frequently Asked Questions About Computed Tomography (CT)

What is CT?
What is a CT scan like?
Who performs a CT?
What are the common uses of CT?
What is the difference between an MRI and a CAT (or CT) scan?
What information do I need to provide WRA staff before my CT?
How do I prepare for a CT scan?
How and when will I know the results of my CT scan?
Where does WRA perform CT scans?
Why should I come to WRA for my CT scan?
Is a CT exam painful?

Screening exams: Cardiac Scoring and Lung Cancer Screening

What is Computed Tomography?
Computed Tomography, also referred to as CT or CAT scanning, is an advanced radiological imaging modality in which an x-ray beam rotates around the patient. CT can image the internal portion of the organs and separate overlapping structures precisely, producing cross-sectional images of all parts of the body.




What is a CT scan like?
You will be asked to lie on a table that slides into a doughnut-shaped ring in the center of the scanning machine. X-rays pass through the area of interest in your body and are detected by an array of electronic sensors. You will feel absolutely no pain. Information from these sensors is then computer processed and displayed as an image on a video screen. Film copies of these images may be made for later study.

A contrast material, sometimes called "dye", may be administered to outline blood vessels or enhance organ images. If a contrast material is used, this will be injected into a vein, usually in your arm. Some or all of the solution may be injected by a syringe or all of it may run slowly into your vein from an intravenous (IV) bottle.

You will be given breathing instructions, then the table will move slowly through the scanner. The entire scan will be completed within minutes.




Who performs a CT?
A radiologist, certified by the American Board of Radiology, oversees the examination. The radiologist will be assisted by a radiologic technologist and possibly a radiology nurse. WRA's radiologic technologists have extensive training in the use of x-ray equipment and will operate the equipment. Together, the highly skilled professionals will make sure that your CT scan produces the best quality images of your body and that you are comfortable throughout the procedure.




What are the common uses of CT?
Most CTs examine the structures in a general part of the body such as the head, spine, abdomen, pelvis and chest. The CT scanner is also useful in determining the size and volume of other tumors and masses. This is especially helpful for cancer patients undergoing radiation therapy or surgery.




What is the difference between an MRI and a CAT (or CT) scan?
MRI does not use x-rays like a CT (computed tomography) scan. With a CT, x-rays are sent through the body, one slice at a time. The computer can then construct the information and create images of the body. MRI involves sending safe levels of electromagnetic waves, such as those used in radio transmission, in a safe magnetic environment. The body then sends out tiny radio waves back to a computer recorder. The different cells in the body can then in turn create their own signal with each molecule having its own radio frequency. The computer can tell the minute differences between the wavelengths of the radio waves and using that information can create an image of the body, one slice at a time.

Because each uses an entirely different technique for imaging the body, the images show different characteristics of the body's anatomy and the diseases that affect them.




What information do I need to provide WRA staff before my CT?
Tell the technologist or radiologist if you are pregnant, diabetic, and/or allergic to any foods or drugs. Let them know if you have had any contrast material in the past and if you had any reaction. Give them a complete list of any medications you may be taking, including non-prescription medications. It is very important that you provide your medical history and reason for this examination. Also, tell them if you have had or, are presently being treated for, an infection in any part of your body.




How do I prepare for a CT scan?
Many CT scans require a contrast agent. The preparation is available at most WRA offices. See exam listing below for specific instructions.

SINUS CT- No preparation

SPINE CT - No preparation for examinations without contrast. For exams with contrast: On the day of your appointment, 4 hours prior to your examination, drink ONLY CLEAR LIQUIDS.

CHEST, HEAD, OR ABDOMEN CT WITHOUT CONTRAST - No preparation

CHEST, HEAD CT WITH CONTRAST
This examination lasts approximately 30 minutes.

Morning Appointments
- 4 hours prior to your examination drink only liquids.

Afternoon Appointments
- 4 hours prior to your examination drink only liquids.

IMPORTANT: Eating solid foods when liquids are required may require rescheduling your appointment.

ABDOMEN, ABDOMEN/PELVIS OR PELVIS CT SCAN WITH IV CONTRAST AND BARIUM
This examination lasts approximately 30-60 minutes.

Morning Appointments
- At 9 pm in the evening prior to your examination drink one bottle of barium.
- Four hours prior to your examination drink ONLY CLEAR LIQUIDS.
- Two hours prior to your examination drink one bottle of barium.

Afternoon Appointments
- At 8 am the day of your appointment drink one bottle of barium.
- Four hours prior to your examination drink ONLY CLEAR LIQUIDS.
- Two hours prior to your examination drink one bottle of barium.

How and when will I know the results of my CT scan?
At WRA, a board certified radiologist will interpret your scan on the same day of your test. He/she will dictate his/her findings and the report will be transcribed and sent to your physician who requested the CT scan. If necessary or requested, the radiologist will call your physician right away. Your physician will then share the results with you.




Where does WRA perform CT scans?
CT scans are performed in WRA's Bethesda, Chevy Chase, Sterling and 2141 K Street, NW offices.




Why should I come to WRA for my CT scan?
Washington Radiology Associates, P.C. is a medical practice owned and operated by board certified physicians whose interest has been providing you the best medical care for over 25 years in the Washington area.




Is a CT exam painful?

If you are having a CT scan which requires IV contrast, you may feel discomfort during the needle insertion. During the CT scan itself you will not feel anything.