CT scan (Computed Axial Tomography)
A CT scan (also called CAT scan) is short for "computer assisted tomography" and is a valuable diagnostic tool for neurological, orthopaedic, heart and vascular specialists. CT scans are more detailed than general x-rays, using computers to generate three-dimensional images from flat, two-dimensional x-ray pictures. Riverside utilizes the innovative 128-slice CT scanner which provides twice the imaging power and half the radiation of conventional scanners. It is the only locally available 128-slice CT scanner. This technology can produce three-dimensional images within seconds and these images are often compared to slices in a loaf of bread. Doctors can look at each slice individual or combine all slices to see the entire image area.
The cross-sectional CT scan shows bones and soft tissue with more clarity than regular x-rays.
CT scans are used in examining injuries to the hands, feet and other skeletal structures because very small bones and surrounding tissues can be seen that aren't easily viewed in an x-ray. CT scans are also used to diagnose cancer, infectious diseases and cardiovascular disease. CT scans are sometimes used in combination with a PET scan.
What to Expect When You Have a CT Scan
Before the Test
You should wear comfortable, loose-fitting clothing and may be given a gown to wear during the procedure.
- You' will be asked to remove your jewelry, hearing aids and eyeglasses because objects with metal may affect the quality of the CT image.
- If a contrast substance or dye will be used during your exam, you may be asked not to eat or drink anything for several hours before your test.
- You will be asked about medications, allergies, recent illnesses and your medical history to make sure you don't have a condition that increases the risk of an unusual or adverse reaction to the test or dye.
- If you are anxious, claustrophobic, or have trouble staying still for any length of time, don't hesitate to talk to your doctor about the possibility of taking a mild sedative you will be prescribed.
CT exams are fast, easy and painless. The CT scanner is a large machine with a short tunnel-like hole in the middle where a narrow examination table slides in and out. Scanners and detectors form a ring that rotates around you when you are inside the tunnel. The CT technologist will operate the scanner and monitor your examination from a separate windowed room, but you will always be in two-way communication with the technologist during the entire test.
Here's what will happen:
- The technologist will position you on the CT examination table.
- If a contrast substance or dye is used, an IV will be started so the dye can be injected through the IV, or, you may be given a substance to take or drink orally.
- The correct starting position will be set for the scans and the table will begin to slowly move through the tunnel.
- As the the CT scanner revolves around you, you will hear buzzing, clicking and whirring sounds.
- The scan takes anywhere from five to 30 minutes.
Following the Exam
Unless you were given a sedative, you will be free to go about your usual activities. Your primary care or referring physician will receive a copy of the images and test report and will discuss the results with you.