A CT scan of the abdomen and pelvis with contrast is a widely used medical imaging procedure. This scan provides detailed images of internal organs and structures within these regions. This article clarifies what this specific scan entails.
Decoding the CT Abdomen and Pelvis
A Computed Tomography (CT) scan uses X-rays and computer processing to generate detailed cross-sectional images of the body. A CT scanner rotates around the patient, capturing multiple images from different angles. These images are compiled by a computer to create detailed “slices” of internal organs, bones, soft tissues, and blood vessels. The abdomen and pelvis are often scanned together because many conditions affect organs spanning both regions.
The term “with contrast” signifies using a special material to enhance the visibility of certain structures. This contrast material, often iodine-based, absorbs X-rays differently than surrounding tissues, making specific areas appear brighter. This enhancement helps medical professionals distinguish blood vessels, organs, and differentiate healthy tissue from diseased areas like tumors or inflammation. Contrast material is typically administered intravenously (IV), though it can also be given orally or rectally, depending on the structures needing enhancement.
Common Reasons for the Scan
Medical professionals recommend a CT abdomen and pelvis with contrast to diagnose many conditions. This scan is useful for investigating abdominal or pelvic pain. It provides detailed insights into organs like the liver, kidneys, pancreas, intestines, and reproductive organs.
The scan can identify issues such as appendicitis, diverticulitis, kidney stones, infections, or fluid collections. It also helps evaluate inflammatory bowel diseases, including ulcerative colitis or Crohn’s disease. This imaging technique plays a role in detecting and evaluating tumors or cancers, assessing their location, size, and potential spread.
Getting Ready for Your CT Scan
Preparation for a CT abdomen and pelvis with contrast involves specific instructions. Patients are usually asked to fast for a few hours before the procedure, often 3 to 4 hours, especially if intravenous contrast will be used. Clear liquids may be permitted up to two hours prior.
Inform the medical team about any medications, especially for diabetes or kidney conditions, as adjustments might be necessary. Disclose any allergies, particularly to iodine or shellfish, though a shellfish allergy does not inherently increase the risk of reaction to iodinated contrast. Wear comfortable, loose-fitting clothing and remove all metal objects like jewelry, belts, and eyeglasses.
Your Experience During and After the Scan
Upon arrival, you may be asked to change into a hospital gown. If intravenous contrast is required, a healthcare professional will insert a small needle into a vein, typically in your arm, to administer the contrast. During the injection, you may experience a warm, flushed sensation and a temporary metallic taste. Some individuals might also feel a brief sensation as if they need to urinate, which quickly subsides.
For the scan, you will lie on a narrow table that slides into the center of the CT scanner, shaped like a large donut or ring. You must remain very still, and the technologist may ask you to hold your breath for short periods to prevent image blurring. The scan itself is painless and usually takes about 15 to 20 minutes.
After the scan, you can typically resume normal activities immediately. To help flush the contrast, drinking plenty of fluids, such as 8 to 10 glasses of water, over the next 24 hours is recommended.
Understanding Safety and Risks
CT scans involve exposure to a small amount of ionizing radiation. The dose is generally low, and the benefits of an accurate diagnosis usually outweigh this small risk. Medical facilities use the lowest possible radiation dose necessary for effective imaging. There is no evidence of radiation from a CT scan making any part of your body radioactive.
The contrast material also carries potential risks. Mild side effects can include nausea, vomiting, headache, itching, or a mild skin rash. More rarely, severe allergic reactions can occur, presenting as difficulty breathing, swelling, or a significant drop in blood pressure. Kidney strain is a consideration, particularly for individuals with pre-existing kidney issues; kidney function may be assessed before the scan. Imaging centers take precautions and have protocols to manage potential reactions, so inform staff about your full medical history and any allergies.