Lavement baryté
A lower gastrointestinal series is a medical procedure used to examine and diagnose problems with the human colon of the large intestine. Radiographs (X-ray pictures) are taken while barium sulfate, a radiocontrast agent, fills the colon via an enema through the rectum. The term barium enema usually refers to a lower gastrointestinal series, although enteroclysis (an upper gastrointestinal series) is often called a small bowel barium enema. For any suspected large bowel disease, colonoscopy is the investigation of choice because tissue sample can be taken for investigation. Virtual colonoscopy (also known as CT colonography) is another preferred investigation, provided that facilities and expertise are available. Virtual colonoscopy also avoids the risk of total blockage of any stricture in the large bowel due to barium impaction. Some conditions are absolutely contraindicated for barium enema namely: toxic megacolon, pseudomembranous colitis, and recent history rigid endoscopy of the large bowel in the past five days and recent history of flexible endoscopy in the past 24 hours. This is because, rigid endoscopy tends to use larger biopsy forceps to take tissue samples from the bowel wall while flexible endoscopy uses small biopsy forceps to take superficial samples. For those with incomplete bowel preparation, the subject can return the next day or the day after next to repeat the procedure. If barium meal was performed recently, then it is advised to wait for another seven to ten days before repeating the procedure. Some frail subject may not be suitable for barium meal. Barium enemas are most commonly used to check bowel health; they can help diagnose and evaluate the extent of inflammatory bowel diseases such as ulcerative colitis and Crohn's disease. Polyps can be seen, though not removed during the exam like with a colonoscopy—they may be cancerous. Other problems such as diverticulosis (small pouches formed on the colon wall that can become inflamed) and intussusception can be found (and in certain cases the test itself can treat intussusception).
