A computed tomography (CT or CAT) scan is a diagnostic imaging procedure that utilizes a combination of x-rays and computers to create images of tissues, organs, and bones. The images produced are more detailed than those created by a regular x-ray.CT scans can be performed on any part of the body. This technology works by using a narrow x-ray beam to move in a circle around the body to provide two-dimensional images from various angles. The information is sent to a computer to create a cross-sectional picture or a “ slice” of the inside of your body. This process is repeated to produce a number of slices, which can be digitally stacked to create detailed images of your bones, organs, tissues, and other structures in the body.
What Are CT Scans Used For?
Your doctor may have ordered a CT scan for several reasons. This procedure can help with:
- Locating tumors, blood clots, or infections
- Showing internal bleeding and injuries
- Guiding procedures and treatments such as biopsies, surgeries, or radiation therapy
- Detecting bone and joint problems
- Detecting and monitoring diseases such as cancer and heart disease
Preparing For A CT Scan
CT scans are typically performed in a hospital or imaging center by a technologist. You may be instructed to avoid eating or drinking anything a few hours before the procedure. You may also be asked to remove metal objects such as jewelry from your body before the scan begins.
During the procedure, you will lie on your back on a table or bed which will move slowly into a large, doughnut-shaped scanner. At this point, you may be asked to stay still and hold your breath because movement can blur the images.
Preparing For A CT Scan With Contrast
Your doctor may have ordered a CT scan with contrast to evaluate parts of your body that may not show up as clearly with a regular CT scan – structures in the body such as soft tissue may appear faint in the image. Therefore, a special dye called a contrast material is needed to block the x-rays and allow the tissue or organ to become more visible.
Contrast materials are typically made of barium sulfate or iodine, which you may receive in one or more of the following ways:
- Intravenously – Injected directly into a vein
- Orally- drinking a liquid that contains the contrast material
- Enema- inserted into the rectum
After completing the CT scan with contrast you will need to drink lots of water and fluids to help your kidneys remove the dye from your body.