X-Ray tests used in diagnosing CCA
CTs, MRIs, ERCPs…the whole alphabet soup of radiographic procedures!
In addition to laboratory tests, your physician may order one or more diagnostic X-Ray exams or procedures to aid in the diagnosis of cholangiocarcinoma. Be sure to notify your physician if you are pregnant or believe you may be pregnant before any x-ray exam.
- Computed Tomography (CT) Scan Also known as CAT Scans, this is an imaging technique that uses computers to create a cross sectional image of the inside of your abdomen. Patients may be asked to drink, a liquid contrast media to help with the imaging. In addition, an intravenous dye may be used during the test to further differentiate normal tissue and tumors. The most common dye used is iodine-based. Be sure to alert the technician if you have an allergy to iodine. In people with kidney problems, the dye may have toxic effects on the kidneys, although most facilities have kidney-friendly dyes available. If you are diabetic, be sure to alert the technician as certain diabetes medications can interfere with the clearance of the iodine dye from the body.
- Magnetic Resonance Imaging (MRI) Scan Magnetic resonance imaging is a non-invasive way to take pictures of the body. Unlike x-rays and computed tomographic (CT) scans, which use radiation, MRI uses powerful magnets and radio waves. The MRI scanner contains the magnet. The magnetic field produced by an MRI is about 10 thousand times greater than the earth’s. The magnetic field forces hydrogen atoms in the body to line up in a certain way (similar to how the needle on a compass moves when you hold it near a magnet). When radio waves are sent toward the lined-up hydrogen atoms, they bounce back, and a computer records the signal. Different types of tissues send back different signals. For example, healthy tissue sends back a slightly different signal than cancerous tissue. Single MRI images are called slices. The images can be stored on a computer or printed on film. Be sure to notify your physician if you have a pacemaker or any type of metal implants such as surgical clips, certain artificial heart valves, artificial joints and older vascular stents, as patients with these should not have an MRI. If you have ever been a sheet metal worker or worked around small metal fragments you may be required to get a skull x-ray prior to MRI to make certain you do not have any metal fragments in your eyes.
- Ultrasound An ultrasound machine creates images that allow various organs in the body to be examined. The machine sends out high-frequency sound waves, which reflect off body structures. A computer receives these reflected waves and uses them to create a picture. Unlike with an x-ray, there is no ionizing radiation exposure with this test.
- Endoscopic Retrograde Cholangiopancreatography (ERCP) Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure used to identify stones, tumors, or narrowing in the bile ducts. The procedure is done through an endoscope. Once the patient is sedated, a catheter (thin tube) is advanced through the endoscope and inserted into the pancreatic or biliary ducts. A special dye is injected into these ducts and x-rays are taken to evaluate them. Narrowing, stones, and tumors can be identified. Special instruments can be placed through the endoscope and into the ducts to open the entry of the ducts into the bowel, stretch out narrow segments, remove or crush stones, take tissue samples, and drain obstructed areas.
- Percutaneous Transhepatic Cholangiography (PTC) — By injecting dye into the bile duct through a thin needle inserted into the liver, blockages can be seen on X-ray.
- Bile Duct Biopsy and Fine Needle Aspiration — A tiny sample of the bile duct fluid or tissue is removed and examined under a microscope. Often these tests are done during ERCP or with CT guidance.