Small bowel follow through exam is a test used to examine the intestines. This is often done after drinking barium contrast. The barium coats the intestines and allows abnormalities to be seen. Multiple X-rays are taken as barium moves through the intestines and reaches the colon. The radiologist will often take additional pictures using continuous X-rays or fluoroscopy. He may press on your abdomen using a glove to spread the intestinal loops apart. You will need to fast before the test, usually starting the evening before.
After you drink several cups of barium, it will coat the esophagus, stomach and intestines. Depending on how your doctor ordered the test, the radiologist may take X-ray pictures of your esophagus and stomach in addition to the intestines. X-ray pictures will be taken every 15 minutes. Sometimes if the barium is moving slowly, xray pictures will be taken less frequently. The radiologist may take additional spot pictures as well between these X-rays.
The test is complete once the barium contrast reaches the colon. Usually this takes between 1-3 hours. I have seen tests run longer than this. The barium coating the intestines allows many abnormalities to be seen like blockages, areas of narrowing, masses, pockets or diverticula, abnormalities of the wall, and an abnormality outside the intestines pushing on them.
The small bowel follow through exam can also be done with other types of contrast when a leak or blockage is suspected. Barium leaking outside the intestines can cause inflammation in the abdomen. If there is a blockage, the test may be stopped before the barium reaches the colon. In these cases, the barium moves slowly and does not reach the colon after many hours.
Barium small bowel follow through exams are done less frequently. CT and MRI tests called enterography can be a better test in many cases. Small bowel follow through exams rely heavily on the skill and experience of the radiologist. The barium small bowel follow through is not done frequently so many younger radiologists do not have as much experience.
Barium small bowel follow through can rule out major abnormalities of the intestines in a relatively quick and non invasive manner. The test is usually well tolerated by patients. The test is not the most sensitive for picking up abnormalities however, and depends heavily on the skill of the radiologist. More modern tests like CT or MRI of the intestines have replaced a big chunk of barium small bowel follow through exams.