A cervical spine CT scan is a medical procedure that uses specialized X-ray equipment and computer imaging to create a visual model of your cervical spine. The cervical spine is the portion of the spine that runs through the neck. Because of this, the test is also called a neck CT scan. Your doctor may order this test if you’ve recently been in an accident or if you’re suffering from neck pain.
The most common reason for a spinal CT scan is to check for injuries after an accident. The exam can help your doctor accurately diagnose potential injuries to this specific area of your spinal column. However, your doctor may also order the test to investigate:
- herniated disks, which are the most common cause of back pain
- birth defects of the cervical spine in children
- tumors that may have started in the spine or somewhere else in the body
- broken bones or areas of potential instability
- infections involving the cervical spine
It can also provide important information if you have certain bone diseases, such as arthritis or osteoporosis, by measuring your bone density. This can help your doctor determine the severity of your condition and identify any weakened areas that should be protected from fractures.
If your doctor is doing a biopsy (tissue removal) or removing fluid from an infected area in your cervical spine, they may use a CT scan of your neck as a guide during the procedure.
A regular X-ray directs a small amount of radiation into your body. Bones and soft tissue absorb radiation differently, so they show up in different colors on the X-ray film. Bones appear white. Soft tissues and organs appear grey, and air appears as a black area.
A CT scan functions in a similar way, but instead of one flat image, many X-rays are taken in a spiral. This provides more detail and accuracy.
Once you’re inside the scanner, multiple X-ray beams move around your upper torso and neck in a circular motion while electronic X-ray detectors measure the radiation your body absorbs. A computer interprets that information to create separate images called slices. These are then combined to create a 3-D model of your cervical spine.
A CT scan takes about 10 to 20 minutes.
In some cases, you’ll need to have an injection of contrast dye. This will help your doctor to see certain areas in your body clearly. If your test requires dye, you’ll receive it through an intravenous line or through an injection near your spinal cord. A nurse will inject the dye before the test begins.
Once you’re ready, you’ll lie on an examination table (usually on your back) that slides into a tunnel at the center of the CT scanner. The table will then move slowly through the scanner while the X-ray beams record images.
Any movement you make while you’re inside the scanner can affect the CT images. You’ll need to stay still during the exam so that the images will be as clear as possible. A pillow and straps will sometimes be used to help you stay in place.
If you know you that have a hard time staying still or if you’re claustrophobic, you may want to ask your doctor for a sedative. This usually isn’t necessary because the exam is very brief.
While the scan itself is painless, you may notice some odd sensations, such as warmth in your body or a metallic taste in your mouth immediately after receiving the contrast dye. That should fade within a few minutes.
If your exam involves the use of contrast dye, you’ll need to make certain preparations. Be sure to tell your doctor if you have allergies, diabetes, or any history of kidney disease. In rare cases, people have an allergic reaction to the dye. It can also cause a negative reaction if you take certain drugs to treat diabetes.
You shouldn’t eat or drink for four to six hours before your scan if you’re receiving contrast dye.
It’s usually recommended that CT scans not be performed during pregnancy unless the benefits of the scan outweigh the risks. If you’re pregnant, you’ll need clearance from your doctor before having this exam.
You’ll need to take off any metal objects, which may affect your CT scan. These include:
- hearing aids
- removable dental work
Some machines have a weight limit. You should let your doctor know if you weigh more than 300 pounds.
As with any procedure involving exposure to radiation, there’s a very slight risk of developing cancer from a CT scan. However, the exposure from any single scan is very low.
You should discuss your concerns with your doctor, particularly if you’re pregnant. The benefits of diagnosing a serious cervical spine problem outweigh any risk from the radiation exposure.
Most people have no issues with the contrast dye. For those who are allergic to the iodine that’s commonly used in the dye, side effects may include nausea, vomiting, or hives. Reactions more serious than that are extremely rare.
After the test, you can go about your day as you normally would. If contrast dye was used during the test, make sure to drink a lot of water to help flush the chemicals from your body.
Results from your CT scan may be available within 48 hours. Your doctor will review the images and determine how to proceed. Depending on your results, they may order additional imaging scans, blood tests, or other diagnostic measures to help get an accurate diagnosis.