Preparing for a CT Scan: What to Wear, What to Avoid and Other Tips

CT scans create detailed images of your internal tissues. Doctors use them to locate, diagnose and monitor the treatment of illnesses and injuries.

If you have been referred for a CT scan, you might wonder what the process entails. This guide will explain what a CT scan is, what to wear to your scan, what to avoid before it and how to prepare.

 

What is a CT scan?

A computed tomography (CT) scan, also known as a CAT scan is an imaging test that uses multiple low dose X-rays to capture cross-sectional internal images. These images, or ‘slices’, are compiled together by computer. During a CT scan, the patient’s exam table is threaded through a rotating ring-shaped array that takes multiple X-ray slices, then digitally compiled into a single 3D image.

To capture a full 360° image, the X-rays are taken along three angles, or views:

• Coronal: the front view, imaging from the front to the back
• Sagittal: the side view, imaging from laterally from left to right
• Axial: the cross-sectional view, imaging from the top to bottom

Depending on what part of the body is being scanned and why, a contrast agent might be used. A type of dye taken internally, a contrast agent heightens the differences between tissues.

 

Why it is done

CT scans provide clear and detailed internal images and thus are used on many different parts of the body to diagnose and monitor a wide variety of conditions, such as illness or injuries in the:

• Abdominal region: to pinpoint appendicitis, bleeding, cysts, diverticulitis, infection, irritable bowel syndrome (IBS) and more
• Blood vessels: including blood clots, blood flow issues, etc.
• Chest: such as issue with the heart, lungs, throat, as well as the major blood vessels
• Limbs: to examine injuries and illnesses in bones and joints
• Organs: including problems in the gallbladder, liver, pancreas, spleen
• Pelvic region: to assess issues in the reproductive organs (e.g. fallopian tubes or seminal vesicles)

 

 

What to wear to a CT scan?

Wear comfortable clothes, as you’ll likely need to remove at least some of them. Depending on the area being scanned, you may be asked to wear a hospital gown and may or may not be allowed to wear underwear. You must remove any metal before a CT scan, including belts, all jewelry and zippers.

 

What to avoid before a CT appointment?

What you need to avoid before a CT scan depends on the body part being scanned. For an abdominal CT scan, you’ll typically be asked to fast for 4-6 hours before your scan, and not drink any liquids for two hours prior. However, that isn’t necessary for a CT scan of your arm. Make sure to check your requisition for specific instructions or call the imaging center if you have any questions.

CT scans use low doses of ionizing radiation and are considered very safe imaging procedures. However, if you have concerns or are pregnant or breastfeeding, you should discuss any potential risks with your doctor.

CT scan procedure: what to expect?

A CT scan is a non-invasive procedure and does not often require extensive preparation. When your CT scan is booked, be sure to ask the imaging clinic for the proper protocol for your type of scan.

How to prepare for a CT scan

Bring your requisition form with you to the imaging clinic, as it contains important information about the type of scan you need. If you have your form with you, you’ll avoid delays when you arrive. Be ready to provide your health card or another appropriate form of ID (depending where you live) at check-in. You’ll likely wait in a general waiting room, in a smaller private waiting room, or both. When you are called, you’ll be given a gown and told what clothes you must remove. Then you’ll be directed to the imaging room.

If you have any questions about your upcoming scan, it’s best to ask them when you book your appointment. Here are a few questions to ask:

• How long will my appointment take?
• What can I wear? Is there anything I shouldn’t wear?
• Can I eat or drink before my appointment? If yes, are there foods or beverages I should avoid? If not, for how long?
• Will I have to wear a hospital gown?
• Will I require a contrast agent?
• Can I have a support person with me?

During the CAT scan procedure

A CT scan appointment takes between 30-60 minutes. The use of a contrast agent adds another half hour, so that the dye is fully absorbed when the scan begins. During a CT scan, you will lie on an exam table that will move through a donut-shaped X-ray machine. The machine will rotate around you taking X-rays, and your table will move in and out incrementally to capture the best images. Here are a few things to be aware of:

• Getting into position takes time: The actual scan takes mere minutes, but getting into the correct placement can take time and effort.
• You might feel claustrophobic: The exam table will move into a tunnel, which can be difficult for people with claustrophobia. You can request a fast-acting medication for anxiety.
• The CT technologist will communicate with you: During the scan, the technician will be in another room, but will be able to hear and speak to you.
• You may need to remain still: The technician may use pillows, straps or an adjustable cradle to ensure proper positioning. You may be asked to hold your breath in certain sections.

The CT scan technician cannot answer questions about the results of your scan but can discuss the procedure itself. You can ask:

• How long will the scan take?
• Is someone else allowed in the room with me?
• Can we pause for a moment?
• Am I in the correct position?

How will I feel after the procedure?

CT scans are non-invasive: after your scan, you can go about your day as normal. If your scan involves a contrast dye, you may be monitored for a short period to ensure you have no adverse or allergic reactions, and you will likely be encouraged to drink lots of liquid to flush the contrast material from your system.

If you have taken a sedative, you will need someone to drive you home. But generally, you can resume normal activities immediately following a CT scan.

 

When will I get my results?

The technician sends your detailed images to a radiologist for analysis. The radiologist forwards a report and the images to your referring physician, who will discuss them with you at a follow-up appointment. The process usually takes 3-5 business days but can sometimes take longer.

If you want secure early access to your CT scan images and report, you can use PocketHealth to obtain them as soon as they are released by the radiologist.

 

 

Understanding my report

CT scan reports often contain complex medical terminology and abbreviations. The more you understand, the better prepared you’ll be for your follow-up appointment.

Who interprets the results?

The technician will forward your CT scan images to the radiologist for analysis and interpretation. The radiologist will send the images and a report to your referring physician for examination, who set up an appointment to discuss the results with you.
There’s no substitute for a follow-up appointment with your doctor. You can examine the results and ask questions, such as:

• What did my CT scan show?
• Are there any abnormalities?
• Do I need any further imaging?
• What are my next steps?

In addition, My Care Navigator can provide you with a personalized list of questions based on your results.

How do I make sense of my results?

CT scan images appear in shades of white, gray and black. The denser the tissue, the lighter it appears on the image. Bone, for instance, is white, while liquid or air-filled tissues are dark.

Your report will discuss any findings, or the observance of any abnormalities in your scan. These might include calcifications, cysts, lesions or masses. If you have any trouble with the technical language, PocketHealth’s Report Reader provides easy-to-understand definitions of medical terms.

For more detailed information, please see our page on How to Read a CT Scan Report.

 

Frequently asked questions

Can I get a CT scan if I’m pregnant?

Always let your doctor know if you are pregnant or breastfeeding, but yes, you can get a CT scan if you are pregnant. Not having a CT scan can present more of a health risk, as it might mean an underlying condition goes undiagnosed.

What happens if I fall asleep during my scan?

It’s possible to fall asleep during a CT scan, though unlikely. The technician will wake you, if necessary, for instance if you need to change position or hold your breath.

Do I need bowel prep for CT scan?

You may require bowel prep for a CT scan of your digestive tract, otherwise bowel prep is not generally required.

Bowel prep is the process of emptying your colon before an internal scan, which involves drinking an oral laxative and plenty of clear fluid the day before your exam. Be sure to ask the imaging clinic about proper preparation when your scan is scheduled.

Do I have to take off my bra for a CT scan?

If your bra contains underwire, you will have to remove it. If not, you may be able to leave it on, depending on the body part being scanned.

Be prepared, informed and proactive with PocketHealth

The more you know about what’s going on in your body, the more informed your conversations will be about any potential diagnosis and ongoing health concerns. Having access to your health records, like your CT scan images and report, puts you in the driver’s seat.

PocketHealth makes that access easy and secure, so you can be confident and in control along every step of your healthcare journey.