The CT or “CAT” scan displays bones and soft tissues in the body. The abbreviation “CAT” stands for Computer Assisted Tomography. Upon the doctor desiring further tests, X-rays are taken and then interpreted by a powerful computer that makes them appear as “slices” through the body. 

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Computer Assisted Tomography (CT)

Upon your doctor examining you to determine what part of the body your pain is coming from, he or she may decide to use a CT scan or Computer Assisted Tomography (CAT) to further examine the inside of your body.  For example, the CT scan will gather additional information in order for your doctor to determine your diagnosis and formulate a treatment plan to bring the very best health care to you.

CT Definition

The Computerized tomography (CT) scan provides an X-ray beam that displays bones and soft tissues in the body.  However, these x-rays are treated differently as they are interpreted by a powerful computer that makes them appear as “slices or cross-sections” through the body.  Also, special software can combine these images into a three-dimensional view of the bones. As such, the image will show soft tissues, blood vessels, and bones of whichever section of the body is scanned. Sometimes your physician may order a CT with and without contrast. For this type of CT, the technician will inject contrast material into the patient’s IV in order to obtain very clear pictures.   

Why Conduct a Computer Assisted Tomography?

The “slices” produced by a CT scan allow the examination of separate sections of the spine.  For example, the images show details of spine bones in great detail.  A CT scan can show if bone spurs are pushing against spinal nerve roots.  It provides an excellent view when looking at fractures or damaged bones due to infection or cancer.  Some doctors began using CT scan technology on a limited basis to test for osteoporosis in the spine.

How to Conduct a CT Scan

You will lie on a table that slides into the CT scanner. The scanner used for Computer Assisted Tomography scans looks like a big circle and the patient goes in the middle of the circle.  The patient will need to lie very still for short periods while the scanner takes many pictures.  When the scan starts you will hold your breath during the scan. This helps to make the image as clear as possible. The procedure takes about 20-60 minutes. The scanner utilizes ionizing radiation to make the image.

What are the limitations?

The CT scan does not show muscles or ligaments clearly.  To make the nerves and soft tissues easier to see, this test can work with a myelogram.  With the myelogram, a technician will cause the dye to enter the spinal sac and outline the nerves and spinal sac so they show up clearly on the CT scan.  A CAT scan without dye does not identify the discs and the nerves of the spine.  The CT scan was developed before magnetic resonance imaging (MRI).  The pictures of soft tissues are not as clear as they are with an MRI.  The MRI shows problems within the disc, particularly a recurring disc herniation. It also shows the health of a disc following surgery.

What are the risks?

The CAT scan uses X-rays. In large doses, the amount of radiation from X-rays can increase the risk of cancer.  The vast majority of patients who undergo a CT scan will never get enough radiation to worry about cancer.  Only patients who must take large numbers of X-rays or hundreds of CT scans over many years need to worry about radiation.  Children, and young adults who plan to have children, will be covered with lead blankets to protect them from radiation exposure to the testicles and ovaries.  Otherwise, the radiation may damage the sperm and eggs. It simply protects these areas by shielding them with a lead apron or lead blanket.

For contrasting CTs, in rare cases, some people are allergic to the contrast material because it contains iodine. If you are allergic to Iodine, please let your doctor know so he can plan accordingly.

IF you are pregnant, your doctor may recommend another exam. Although the American College of Radiology does recommend that pregnant women should consider another type of exam if possible, such as an MRI or ultrasound.

Female patient in CT scanner

CT procedure for spine series exam.

Cervical Spine CT Scan

An example of the CT image your physician
will receive to review your anatomy.

If you or a loved one suffers from spinal pain, you owe it to yourself to call Southwest Scoliosis and Spine Institute at 214-556-0555 to make an appointment.