Computed Tomography (CT)
CT Scans : creating cross-sectional pictures without surgery
A CT (Computed Tomography) scan is sometimes referred to as a CAT scan. It uses a special X-ray machine to take images of cross-sections of your body. This enables the doctor to see clearly what is going on in different parts of your body without surgery. Because it can easily look at various types of tissues, bones, blood vessels, and soft tissue, a CT scan can help with diagnosing a wide range of conditions including cancers, infectious disease, bone disorders, internal trauma, or cardio-vascular disease. Some of the CT scans performed at SIRA include chest, abdomen and pelvis, skeletal, head and neck, facial, cardiac scoring and lung cancer scoring.
How does it work?
The CT machine is a doughnut-shaped machine with a sliding table that goes through its center. A special x-ray unit rotates around the ring, taking multiple pictures of the inside of your body. These pictures are then interpreted by a special computer which prints very detailed, two-dimensional pictures of cross-sections of your body. The exam usually takes 15-30 minutes.
How to prepare for your CT scan
You may not have to do anything to prepare for this exam, depending on what area of your body is being scanned, but be sure to ask your physician when the appointment is scheduled. You may be asked not to eat or drink anything for a period of time before your exam, or to drink barium before the exam. If you are receiving IV contrast, you may also need to have blood work done prior to your appointment.
On the day of your appointment, wear loose-fitting clothing with no zippers, snaps or other metal. You may be asked to remove all jewelry, glasses, removable dental work, or hearing aids. You MUST inform the technologist if there is a chance that you could be pregnant. If you are diabetic, over age 65 or have kidney problems, you will need BUN and creatinine exams before the exam. Also, you may need to be pre-medicated if you are allergic to iodinated contrast (IVP contrast).
What to expect at your appointment
You will be positioned on a special table which will carry you into the CT unit. Depending upon the type of exam you are having, you may be required to drink, or receive an injection or sometimes an enema consisting of a contrasting agent. The IV contrast may cause you to feel a sudden flush of warmth or to have a metallic taste in your mouth. This is normal and will go away soon. There is a very slight chance of a reaction, so if you develop shortness of breath, itching, or changes in swallowing, tell your technologist immediately.
Your technologist will make sure that you are in the best position possible to assure the most helpful pictures for the radiologist. You may be propped on pillows in order to accomplish this.
Your table will carry you into the machine. While the machine is working, your technologist will be behind a glass panel in the control room so that s/he can monitor the progress of your scan. The technologist will still be able to talk to you through a microphone.
As the machine takes its pictures, you will hear a whirring noise, but the exam is completely painless. After it is over, you may be asked to wait for a few minutes while the radiologist determines if the pictures are sufficient.