Which test can be useful in diagnosing and treating digestive system disorders
|
Many digestive conditions cause symptoms that are similar, but the treatment for the conditions can be very different. As a result, your provider may need to perform testing — including blood tests — to confirm a diagnosis. Show
Blood tests can show levels of specific substances in the blood. Digestive issues for which blood tests support a diagnosis include Celiac disease, inflammatory bowel diseases (Crohn’s disease and ulcerative colitis), stomach ulcers, stomach cancer and food allergies. Preparing for a blood test Preparing for a blood testSome blood tests may require special preparations, such as fasting or discontinuing specific medications. Your care provider will let you know which preparations to take. If you’re not told to fast, you should drink plenty of water and follow your regular diet. During the blood test During the blood testBlood tests are usually a quick and common procedure. The area the blood will be drawn from — usually the arm, either near the elbow or the wrist — is usually wrapped tightly with a band to make the vein easier to see, and then the access area is cleaned with an antiseptic wipe. The skin is pierced with a needle attached to a collection tube, and blood flows from the vein and into the collection tube. Once the appropriate amount of blood is collected, the needle is removed and a bandage is placed over the site. Some discomfort and bruising at the injection site may be experienced. Blood test results Blood test resultsLaboratory workers analyze the blood, looking at specific blood factors. Blood test results could be available within minutes or take a few weeks to be ready. Your doctor will discuss the test results with you. A CT scan, computed tomography, takes multiple X-rays of the body from different angles in a very short period of time. These images are collected by a computer to give a series of "slices" of the body, which can help doctors determine what is causing your symptoms. CT AngiographyThis test combines a CT scan with the injection of a contrast dye that highlights blood vessels and tissues in the abdomen. Virtual ColonoscopyNew technology has made it possible for a computer to take CT images of the colon and reconstruct a three-dimensional model of your colon -- called a virtual colonoscopy. The inside of this model can be inspected, obviously without causing any pain to you, while searching for abnormalities. However, if an abnormality is found, a scoping test, either sigmoidoscopy or colonoscopy, will be needed to get a tissue sample. Magnetic Resonance Imaging (MRI)MRI produces very clear pictures of the human body without the use of X-rays. MRI uses a large magnet, radio waves, and a computer to produce these images. The MRI examination poses no risk to the average person if appropriate safety guidelines are followed. Radionuclide ScanningAlso called nuclear scanning, radionuclide scanning is a test in which the patient either swallows, inhales, or is injected with a small amount of radioactive material. A special camera is used to detect the radioactivity, producing images of organs and areas of the body that can't be seen well with standard X-rays. Many abnormal tissue growths, or tumors, are particularly visible using radionuclide scanning. In addition to showing the structure of an organ, radionuclide scanning allows the doctor to see how the organ is functioning. A diseased or poorly working organ will appear differently on the scan than will a healthy organ. The information from this test is valuable in diagnosing many diseases, including cancer. Because this test shows internal areas that are not visible on standard X-rays, radionuclide scanning can also help identify problems very early in the progression of a disease. Although radiation is used in this scanning technique, the test is very safe. The actual dose of radiation you receive is quite low and stays in your body only for a short time. Drinking plenty of fluids after your scan will help to eliminate any radioactive material from your system. Upper and Lower GI Tests Upper GI tests use X-rays to examine the esophagus, stomach, and first part of the small intestine (the duodenum). For these tests, you need to drink a chalky liquid called barium. As the barium passes through the digestive tract, it fills and coats the esophagus, stomach, and first part of the small intestine making them more visible with X-ray. Then a fluoroscope machine is held over the part of the body being examined and transmits continuous images to a video monitor. This upper GI test is used to diagnose:
Lower GI tests or barium enemas are used to examine the large intestine and the rectum. For this test, barium or an iodine-containing liquid is introduced gradually into the colon through a tube inserted into the rectum. As the barium passes through the lower intestines, it fills the colon, allowing the radiologist to see growths or polyps and areas that are narrowed. The fluoroscope machine is held over the part of the body being examined and transmits continuous images to the video monitor. The lower GI test is used to detect:
Abdominal ultrasound The ultrasound machine sends out high-frequency sound waves that reflect off body structures, sending them to a computer that creates a picture of organs and structures in the abdomen. This is done with a handheld probe, called a transducer, which is moved over the abdomen. There is no exposure to radiation with this test. Abdominal X-ray A small amount of radiation is used to take a picture that is recorded on film or a computer.
SOURCES: Radiological Society of North America (RSNA). National Institute of Diabetes and Digestive and Kidney Diseases Clearinghouse (part of National Institutes of Health). |
