Patient's Guide to CT
What is CT?
A "CT Scan" is the term used to describe a radiologic test known as "Computerized Tomography". The CT scanner is a doughnut shaped machine that uses advanced x-ray technology to take pictures of your body. A computer then reconstructs the data into cross-sectional pictures of your body, called slices or sections.
What do I need to know about my CT scan?
Our staff is always available to answer any questions that you may have and help you through your exam. Our staff is well trained to ensure your visit is pleasant and safe.
Before your CT Scan
What should I eat or drink?
Please do not eat solid foods for four hours prior to your CT appointment. You may drink clear liquids (black coffee/tea, broth, water or juice) prior to your CT scan. If your exam includes the administration of IV contrast medium, do not drink anything within four hours of your exam (except for small sips of water with your medications.)
What medications should I take?
Please take all regular medications that your doctor has prescribed for you.
What if I am allergic to IV contrast material (IVCM)?
If you think you may be allergic to IV contrast material or have experienced a prior reaction to IV contrast material please notify your referring physician prior to scheduling your CT scan appointment.
Might the IV contrast harm my kidneys?
If you have a history of kidney disease or are at risk for kidney disease please notify your referring physician prior to scheduling your CT scan appointment.
What should I wear?
We encourage our patients to wear loose, comfortable clothing that does not have any metal buttons, snaps or zippers. Otherwise you may be asked to change your clothes and wear a hospital gown. We have private dressing rooms with lockers for your clothes and valuables, however it is best to leave all valuables at home. We may ask you to remove any jewelry, dentures, glasses or any metal objects which may interfere with the CT scan.
What should I bring for my appointment?
You will be required to bring your blue BWH hospital card, your insurance card, and any related insurance forms or pre-approvals.
At the time of your appointment
When should I arrive for my appointment?
Please plan to arrive at the CT suite 30-60 minutes before your scheduled appointment. This will allow time to prepare your paperwork. You will be asked to fill out a brief questionnaire about your medical history, medications, allergies, and insurance.
If you are having a CT scan of your abdomen or pelvis, you need to arrive 1 hour and 15 minutes before your appointment. You will be asked to drink oral content material (either Barium, lodine, or water). These help mark your intestinal tract so that the radiologist may interpret your scans properly. You will then be asked to wait for one hour before the examination, because it takes that long for the drink to coat your stomach and small intestine. In fact, depending on your medical problem and the type of study that has been requested, you may be asked to drink one bottle of barium sulfate at bedtime the night before the study.
Will your staff know me and why I am here?
Throughout your visit you will encounter many of our staff members who will ask you a series of repeated questions related to your identity and procedure. This is to assure your safety while we provide your care, and is not because we do not know you or what procedure you are having.
Will I need an IV (Intravenous) for CT scan?
The referring physician and the radiologist will determine if IV contrast material will enhance your CT scan. IV contrast material (IVCM), containing iodine is used to highlight organs and blood vessels that are otherwise difficult to visualize. The IVCM that we use, has a low iodine content which reduces the chance of an allergic reaction and the discomfort associated with the injection. If we decide to use IV contrast material for your CT scan, a small IV will be placed in your arm or hand prior to the CT scan. During the CT scan a technologist will closely monitor the IV contrast material injection and you to ensure an accurate and safe scan.
Will I have to drink something for my scan?
Abdominal CT scans may require the administration of water, or oral contrast material. Oral contrast materials are barium or iodine based. Barium-based contrast material is a thick white flavored drink similar to a milk shake. Iodine-based contrast material is a concentrate that is mixed with water or juice. For optimal imaging, approximately one liter of oral contrast material should be consumed during the hour prior to your scan.
What will happen during my scan?
A staff member will escort you to a CT suite where you will lie down on the CT table. The CT table will move in and out of a large hole in the doughnut shaped CT scanner. While the table is moving, an X-ray is produced to create the CT images. If for your particular CT scan you are required to hold your breath we will give you breathing instructions asking you to take in a deep breath and hold it. After some initial imaging, if an IV contrast material injection is necessary for your scan, a technologist will enter the room and begin your IV contrast material injection. The high tech CT scanners at BWH mean that most CT exams last approximately 10-15 minutes.
After your CT scan
Once your scan is completed you may resume your regular diet and activities. We recommend that you drink plenty of non-alcoholic, decaffeinated fluids such as water or juice to help your body flush out any IV or oral contrast material.
How will I know the results of my CT scan?
After your CT scan a BWH radiologist will read the images, using all available prior imaging. A final report of the CT scan will be available to the physician who requested the CT scan and who will discuss the results with you.
This page was last modified on 6/6/2014