CT Scan FAQs

You can learn more about CT scans from these answers to frequently asked questions.

Why do I need IV contrast?

Contrast is injected through a vein in your arm and shows up as bright on a CT image. It helps our radiologists identify and characterize certain diseases. It is so useful that in certain studies, such as abdominal CTs, it is almost always utilized.

Will I be allergic to the contrast?

A small percentage of patients will have an allergic reaction to iodinated contrast (which is used in IVPs). Patients should alert their doctors if they have had an allergic reaction to contrast in the past. If they have had a prior allergic reaction they may be given medication to prevent a repeat reaction. If a patient has an allergic reaction during the exam our radiologists are prepared to deal with these situations.

When will my doctor get a report?

Emergency or STAT reports are called to your doctor following completion of your examination. He Your doctor will have a report faxed within 24 hours, and have the official typed report within 24-48 hours.

How long will the study take?

The length of time varies with the type of study. Some can be performed in less than five minutes; others can take thirty minutes or longer. The average length of time is between fifteen and twenty minutes.

Does the oral contrast give/cause diarrhea?

The oral contrast can cause you to have more frequent bowel movements but it should not cause diarrhea.

Will this hurt?

Usually not, although portions of certain exams are uncomfortable. For example, contrast requires the insertion of a needle into a vein. Also, when the contrast is injected it can make you feel warm over your chest and head. This feeling rapidly disappears.

How much radiation am I getting?

The radiation dose varies with the part of the body being imaged. Every effort is made to limit the amount of radiation exposure a patient receives.

I have a sulfa allergy, is barium sulfate the same thing?

No. Barium sulfate is totally unrelated to sulfa medicines. Barium can be safely ingested regardless of allergies.

What is the difference between an MRI and a CT?

An MRI uses a powerful magnetic field for imaging; a CT scanner uses x-rays. Both are powerful tools for imaging, and each has certain things it images better than the other. For example, MRI is better for imaging the knee, whereas CT is better for imaging the lungs. The two are complementary in many parts of the body. For example, it is not unusual for a CT of the liver to show an abnormality, and then an MRI to help further characterize it.