Making a Back Pain Diagnosis: Imaging Tests - Computerized Tomography (CT or CAT) Scan
X-Ray medical imaging shows only the bones and spaces between the bones where your intervertebral discs are. If a soft-tissue problem is suspected, more sophisticated medical imaging tests (such as the CT Scan or MRI) may provide more information useful to the diagnosis of back pain. The soft tissue refers to the tissues of the musculoskeletal system, other than bone, which surround, support, or connects the bones, muscles, and other structures of the body. Let's take a look at how the CAT scan images the soft tissues and other structures of the musculoskeletal system.
Computerized Tomography (CT or CAT) Scan
Referred to as CAT Scans or CT scans, computerized tomography involved using a computer to record two-dimensional "slice" images of your body. For some procedures and body structures, these 2-D slices can be combines into a 3 dimensional view of the back and spine. This procedure may help doctors to observe and diagnose the following causes of back pain: infections or tumors of the spinal cord, spinal stenosis, herniated discs, and ruptured or herniated discs. The CT, like the X-Ray, and unlike the MRI, used radiation to form the 2-D and 3-D medical images. The CT used more radiation to create more detailed images, but the amount of radiation is considered safe. The CT provides a cleared and more detailed view of the structures of the back than the X-Ray.
Like the MRI, the CT scan involves patient lying on a table that slides into cylindrical tube to take the medical images. Both of these procedures may be difficult for patient with claustrophobia. To perform the CT scan, the technician will have you lie on your back on a narrow table, which will then slide into a cylinder-shaped machine. If you have difficulty getting on/off the table, one or more of the technicians will be available to help you.
The procedure itself is painless. You cannot feel the radiation exposure involved in creating the images. However, some of these procedures involve the injection of a radioactive dye, called radiocontrasts, into a vein in order to illuminate certain structures being photographed during the procedure. Some people may find the injection to be uncomfortable or painful. Also some people who are injured, have a chronic condition, or who are uncomfortable being in enclosed spaces, may find it difficult to lie on their back for the duration of the procedure. Most CT procedures generally last 30-45 minutes.
The advantages of the CT Scan are that they provide detailed, clear pictures of soft-tissue structures, in addition to the bones of the spine. These scans also show in-depth detail of the blood vessels, tendons, discs, ligaments, cartilage, and muscles. When diagnosing the cause of a patient's pain, these images may be much more useful that those of an X-Ray, since the cause of back pain in most individuals are not due to problems of the bones.
CT Scan with Myelogram: CT scan with Myelogram together may be an excellent diagnostic procedure to determine the cause of back pain causes such as sciatica and nerve root compression. A myelogram involves the injection of a radiographic dye into the dura (the sac around the nerve roots), which will illuminate this area when the image is produced.