About Dr. Vergilio
About abdominal ultrasound
About Barium Enema
About colonoscopy
About CT Scanning
About endoscopy
About ERCP
About HIDA scans
About liver biopsy
About sigmoidoscopy
About upper GI and small bowel series
Tummyhealth (R) diet
Upper Abdominal Pain
Abnormal liver function tests
Barrett's Esophagus
Bloating Gas and Flatuence
Cancer information links
Colon cancer
Sprue (Celiac disease)
Concepts for Weight Loss
Crohns disease/Ulcerative colitis
Gallstones/Gallbladder disease
Irritable Bowel Syndrome
Links to Other Sites
Ulcer disease
Hepatitis A
Hepatitis B
Hepatitis C
Hepatitis C (Advanced)
Hernias Made Easy
Hiatal Hernia
Lactose intolerance
Laparoscopic surgery
Overview of the Digestive System
Stopping Smoking and Staying Slim
Swallowing difficulties (dysphagia)
Digestive Dictionary (from NIH)
Delayed stomach emptying (Gastroparesis)
USDA Food Guide
Wilson's disease
Terms and Conditions of Use




CT (CAT) scan stands for computed axial tomography scanning.  It gives physicians an excellent way to look at many features of the digestive tract.  It is particularly useful in checking the liver and pancreas, which are not easily examined by other methods used for the imaging of the digestive tract.  It is useful to check for causes of abdominal pain especially when other less expensive and less intensive methods such as plain X-ray are not helpful in diagnosing the pain.  It is also good for looking for small tumors, abscesses, and abnormalities that are hard to pick up otherwise.  It is used to stage (define the spread of) cancers, and is excellent for tracking the presence of abnormal lymph nodes in the abdomen and pelvis.  The test works by sending a fine stream of X-rays through your body from many different angles, and combining these results with powerful computers to come up with very detailed images of the interior of the body.  The scan is presented as "slice" pictures, across the axis of the body, to a radiologist who interprets the many images to give a diagnosis of the presence of an abnormality.

The test preparation begins several hours before the actual exam when you drink several small bottles of contrast material that highlights the intestines and makes the pictures obtained more informative and easier to read.  An intravenous line is often started to give intravenous contrast material.  This IV material makes the detection of abnormalities in solid organs like the pancreas, liver, and kidney easier to find.  The injection of contrast material often gives a "warm" feeling through the body.  Some patients with preexisting allergies take oral steroids before the exam to help prevent allergic reactions to intravenous contrast.

If you are older, or have a history of vascular disease, diabetes mellitus, or kidney disease, a blood test for serum creatinine will usually be performed first to determine whether the dye can be safely used. Your physician makes the decision as to which types of contrast can be used.  The test, which takes five to twenty minutes to perform, is done as you lie flat on your back on a table that is slowly moved through the hollow center of the CT scanner.  Unlike the MRI, most patients do not find the CT scanner claustrophobic or problematic. Risks of the testing include the modest radiation exposure; the possibility of leakage of the dye outside of the intravenous line under the skin, causing a reaction; the possibility of allergic reactions to the contrast material, and the possibility of kidney problems or failure from the contrast, especially those who are older, diabetic, or those who take certain medicines.  Be sure to discuss with your doctor all your conditions prior to undergoing a CT scan.

The CT scan provides high-quality pictures that make it possible to identify abnormalities as small as 0.5 cm, but it is not a perfect test, and it has its limitations. While the scans can point out structural problems and can suggest a diagnosis, a CT in itself is rarely conclusive.  It can miss pathology when it is isodense (the same density) with surrounding tissues.  The accuracy of the test is also highly dependent on the person reading it.  It is also expensive.  However, it often is of great help in establishing a diagnosis for abdominal maladies.