CT Scan

What is the difference between MRI and CT?

MRI or Magnetic Resonance Imaging uses a powerful magnet and radio waves to send images of the body to a computer. There is no radiation in MRI. CT or Computed Tomography uses radiation and a computer to create images. CT scans are faster than MRI scans and it is more often necessary to drink an oral contrast agent for CT. Both MRI and CT often use intravenous contrast agents given thru an I.V. catheter placed in the arm. MRI makes more noise during the exam compared to CT scans.

Will I have to take off any metal items (like a MRI)?

Articles of clothing containing snaps or zippers, as well as jewelry may need to be removed if they are on the area of the body being scanned. You will be provided with a gown when necessary.

How long will the scan take?

CT scans are 5 to 15 minutes depending on the area of the body being scanned. Your exam may require special preparation with oral contrast agents that may take 30 to 90 minutes if you have not picked up contrast from one of our locations prior to your exam date.

Why do you have to leave the room?

The CT scanner is controlled from an advanced computer console that can only be operated by the technologist. There is a window between the scan room and the operator console. The technologist is able to see you and communicate with you thru the entire exam.

Will it hurt?

The CT examination requires you to lie still and follow special breathing instructions for short periods of time, which should not cause pain. It may be necessary to have an I.V. Catheter placed in your arm which would be similar in experience to having your blood drawn and may cause discomfort.

I want sedation (it’s only a 5 minute exam).

Most patients are able to tolerate a CT scan, which is more open than MRI. The exams are significantly shorter in duration and usually only require the head to be under the scanner for very short periods of time.

How much radiation am I receiving/getting?

The amount of radiation exposure depends on the different areas of the body being scanned as well as patient size. Our goal is to acquire quality images at the lowest radiation dose possible. Advancement in technology provides us with the capability to achieve this goal and we can compare an individual scan to the amount of natural background radiation accumulated we receive from the atmosphere. Special considerations are given by our radiologist for pediatric patients making it possible to lower the dose significantly.

Why didn’t my doctor tell me I need to drink something?

Most doctors allow the use of contrast agents, those you drink, as well as those injected at the discretion of the radiologists. Depending on the area of the body being evaluated, as well as your symptoms and medical history, contrast agents are given to improve the quality of your exam. Images of your body are better evaluated with the use of contrast agents.

Why do I have to drink barium?

Barium and other forms of oral and I.V. contrast agents improve the quality of the images. They provide better visualization of different areas of the body.

What is contrast?

Contrast agents commonly used in CT are oral agents such as flavored Barium, Water, juice with iodinated contrast material and I.V. contrast injected into a vein in the arm. All are used to provide better visualization of the different organs in the body and greatly improve the quality of your exam.

Can I breastfeed my child after receiving an intravenous contrast agent for my exam?

The American College of Radiology has provided information to help nursing mothers to decide whether to breastfeed after receiving a contrast agent for an MRI or CT. Please review Contrast Agents and Breast Feeding – Recommendations for details.

Why do I need an injection?

It may be necessary to inject I.V. contrast to improve the quality of your exam and better evaluate the organs of the body. I.V. contrast improves visualization of the different soft tissues in the body.

How will the IV and/or oral contrast affect me?

You may experience a hot sensation in different areas of your body while receiving I.V. contrast, this sensation is common and expected. You must inform your Doctor and our staff if you have ever experienced difficulty with x-ray dye or iodine. Special medications may need to be prescribed before your exam if you have a history of past allergies to x-ray dye or iodine.

Can someone come in the room with me?

It is possible for a family member to accompany you as we prepare for the examination. They will then be asked to leave the scan room during the actual scan. Special consideration will be made for children and patients needing further assistance.

Can I eat, drink or drive after the exam?

You will be able to return to normal activity following your CT scan. You may be given special instructions to follow for certain health conditions.

Will you call me with the results?

Our radiologist will evaluate your CT exam and a report of these results will be sent to your doctor within several business days, sooner at your physician’s request.

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