CHAPTER 6
TESTS A�D SCA�S
There are several tests that your specialist may want to perform to confirm your diagnosis . It is important to understand how these tests work , why your specialist orders them and what the terminology means in plain language .
What is a CT scan ( CAT scan )?
Computed tomography or CT scans have been with us for many years and are performed for many different disease entities . A CT scan is made up of ordinary X-rays ( tomograms ) that are fed into a computer ( computed ). They can be performed following administration of a contrast medium that is injected into the patient ’ s veins . This contrast medium is usually iodine-based and circulates in the vascular system of the body . It is taken up in areas where there is increased blood flow like areas of inflammation , infection or cancer . It is also used to examine patients ’ arteries and veins .
A CT scan is the best test to evaluate the integrity , alignment and pathology of the vertebrae of the spine . It is not as efficient when evaluating the softer tissues such as discs , ligaments and nerves as MRI scans , which are the best for evaluating softer tissues .
When undergoing a CT scan , you are placed in a large machine that is shaped like a doughnut . The table you are lying on will move forward and backward as the scan is being performed . Older-generation CT scanners could do only one slice ( exposure ) at a time ; modern scanners do many cuts at the same time and are much faster .
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