A Neck Computed Tomography Angiography (CTA) is a medical imaging test that provides detailed pictures of the blood vessels within the neck. It combines a specialized X-ray machine with an injectable contrast material to highlight these vessels. The scanner takes numerous cross-sectional images from different angles, which a computer processes to create comprehensive, three-dimensional views of the arteries and veins.
Purpose of a Neck CTA
A physician may order a Neck CTA to investigate symptoms or to plan for medical procedures. The detailed images help diagnose and evaluate several conditions affecting the neck’s blood vessels. It is frequently used to identify carotid artery stenosis, a narrowing of the main arteries that supply blood to the brain. The scan can reveal the extent of plaque buildup, a fatty substance that can restrict blood flow and potentially lead to a stroke.
Another purpose is to detect aneurysms, which are bulges or weak spots in the wall of a blood vessel. The test is also effective for identifying an arterial dissection, a tear in the inner layer of an artery’s wall that can occur after trauma to the neck. Additionally, a Neck CTA can be used to assess for vasculitis, a condition involving inflammation of the blood vessel walls, or to pinpoint blockages and blood clots. The scan is also a tool for surgical planning, particularly before procedures like carotid endarterectomy.
Preparing for the Procedure
You will be instructed to fast, meaning you should not eat or drink anything for about four to six hours before the scan. Drinking clear fluids like water may be permitted up until two hours before your appointment, but you should confirm this with the imaging center.
It is important to inform the medical staff about your health history. Tell your doctor and the technologist if you have any allergies, especially to iodine or shellfish, as the contrast material contains iodine. You must also disclose any kidney problems or if you take metformin for diabetes, as you may be given specific instructions.
On the day of the scan, wear comfortable, loose-fitting clothing. You will be asked to remove any metal objects, such as jewelry, eyeglasses, and dentures, because metal can interfere with the imaging equipment. You may also be asked to change into a hospital gown.
What to Expect During the Scan
A technologist will explain the procedure and place an intravenous (IV) line into a vein in your arm or hand. This IV is used to administer the contrast dye. You will then be asked to lie on a narrow examination table, which slides into the center of the large, doughnut-shaped CT scanner. It is important to lie as still as possible during the scan, as movement can blur the images. Straps and pillows may be used to help you maintain the correct position.
Once you are positioned, the technologist will leave the room but will be able to see and speak with you through an intercom. The scanner will begin to rotate around your neck to capture the images. During the scan, the contrast dye will be injected through your IV. It is common to experience a warm sensation or a temporary metallic taste in your mouth; these feelings are normal and pass quickly.
You may be asked to hold your breath for short periods to ensure the images are clear. The entire scanning process is quick, often lasting only about 10 minutes.
After the Scan and Receiving Results
Immediately following the procedure, the technologist will remove the IV line from your arm. Most patients can return to their normal activities and go home shortly after the scan is complete, with no restrictions on driving or eating. The primary post-procedure instruction is to drink plenty of fluids for the rest of the day. Consuming extra water helps your kidneys flush the contrast dye from your system.
While the images are captured in minutes, the results are not available immediately. A radiologist, a doctor specializing in medical imaging, will analyze the pictures from your scan and compile a formal report. This report is sent to your referring doctor, and you will schedule a follow-up appointment to discuss the results and potential treatment plans.
Potential Risks and Considerations
While a Neck CTA is a safe procedure, it involves considerations related to the contrast dye and radiation. Some people may have an allergic reaction to the iodine-based contrast material. Most reactions are mild, causing symptoms like itching or hives, but in rare cases, a more serious reaction can occur. The contrast dye also poses a risk of kidney damage, particularly for individuals with pre-existing, severe kidney disease.
The scan utilizes X-rays, which means you will be exposed to a low dose of ionizing radiation. Modern CT scanners use the lowest possible radiation dose to obtain high-quality images. Although the risk from a single scan is small, physicians order a Neck CTA only when the diagnostic benefits outweigh the associated radiation risks.