CT (Computerized Tomography)

CT equipment rotates around a patient to take X-rays from every direction and assemble those images into detailed, cross-sectional images. CT scans are used to study and diagnose conditions in almost every part of the body, including the heart—where studies are known as Coronary CT Angiographies, or CTAs.

At Northwestern Lake Forest Hospital Diagnostic Imaging Centers, we offer the following types of CT scans:

• Low-Dose CT Scans
• Cardiac Scoring
• CTA, or coronary CT angiography

Certain CT studies require the use of a contrast medium.  Contrast media are used to optimize imaging studies as prescribed by the referring physician.  Depending on the test, you may drink the contrast medium or have it injected; some tests require both.  Please alert our staff if you have renal or kidney problems.

How is a CT performed?

During the exam, you will be asked to lie still on the examination table.  In many cases, it is not even necessary to undress.  For certain procedures, the technician may ask you to hold your breath.  If you require a contrast injection, the process will be explained to you and any questions you may have will be answered.

An X-ray tube will rotate around your body, taking pictures.  A computer program is then used to project images on a monitor.  The images will show a cross-section of body tissues and organs that are then studied by the radiologist.

How is a CTA performed?

The scan is performed in less than 10 minutes and does not require sedation.  Patients undergoing a Coronary CTA scan receive a contrast dye as an IV solution to ensure the best images possible.  The same IV in the arm may be used to give a medication to slow or stabilize the patient's heart rate for better imaging results.  We will also place ECG leads on your chest before the initial scan is performed to assess the amount of calcification in the coronary arteries.  The scan itself takes approximately 10 seconds to acquire the image.

How do I prepare for a CT?

Most exams take less than 30 minutes.  Studies with contrast require you to fast for 3 hours prior to the test.  As with all radiological procedures, you should inform the technologist if there is any chance of pregnancy or if you are nursing.

Studies of the abdomen and pelvis with contrast require patients to drink oral contrast after they arrive at the office for their appointment.  Please allow an additional 30 minutes to the total exam time for this.

If you have ever had a severe allergic reaction to food or medicine in the past, have asthma or a prior reaction to a contrast material during previous CT scan or X-ray, please advise the office at the time of scheduling.

 

For more information, please contact your physician or our main Radiology (Diagnostic Imaging) office at (847) 535-6300.