If you've had your colon -- part of your large intestine -- removed for ulcerative colitis or colon cancer, you likely have had a temporary ileostomy. When the colon is excised, surgeons connect the end of the small intestine directly to the anus. Diversion of fecal material through an ileostomy that's positioned higher up in the digestive tract protects this new connection between your small intestine and anus until healing occurs. A subsequent surgery closes the ileostomy so that all stool again passes out of the anus.
A special x-ray, called a contrast enema or "dye test," may help determine if your new connection, known as an "ileo-anal anastomosis," will function properly once surgeons reverse your ileostomy.
Purpose
After removing all, or part, of your diseased colon, surgeons create a "pouch" out of your small intestine to take over the colon's function of storing stool. Your surgeon will either sew or staple the end of this small intestine pouch to a rectal stump, just inside the anus, or to the inside of the anus itself. As with all surgical incisions, this internal suture line must heal before acquiring enough strength to function properly, without separating or leaking. Leakage of stool into the abdominal cavity leads to life-threatening infections in some people, so verification of a healed anastomosis can help avoid complications.
The dye test allows doctors to visualize the pouch and the anastomosis. They can see any leaks or any blockages that will cause complications and decide if the pouch functions as expected.
Time Frame
Most surgeons have guidelines regarding the minimum interval between creation of an ileo-anal anastomosis and reversal of the ileostomy. The standard time between operations averages about eight to 12 weeks, as reported in a literature review of the subject, published in the "Journal of the American College of Surgeons," in 2005.
The dye test to investigate your pouch will usually occur about a week before your anticipated ileostomy take-down. If the radiologist sees any leakage or other issues with the pouch, your surgeon will delay your operation by three to six months to allow for more healing time.(5)
Preparation
Some research, such as a 2007 study published in the journal "Digestive Surgery," suggests that only higher-risk patients need to have the dye test, because routine use in every patient does not change the timing of ileostomy reversal in most cases. Your doctor, therefore, may or may not order this test.
If your surgeon requests this test, you will receive instructions about any preparation required before your test. Some institutions require a period of fasting, or a clear liquid diet, from eight to 12 hours prior to the test.
Technique
Usually, this test takes place in the radiology department of a hospital. A radiology technician or a radiologist will perform the test. You change into a hospital gown and lie down on your side. Gentle insertion of a small tube into your rectum introduces dye into your small intestine. Sometimes the contrast injection occurs through the ileostomy opening instead. This contrast material lights up on x-ray film and shows the structure and filling of the pouch. X-ray pictures and movies show the contrast moving along the gastrointestinal tract. The radiologist takes special care to look at the suture line and notes whether or not leakage out of the pouch occurs.
Minimal cramping on injection of the dye occasionally becomes bothersome, but most people describe this test as quick and painless.
Warnings and Risks
This test presents little risk, but you may wish to review the procedure and address several issues before proceeding.
The radiologist should know that you have had your colon removed and have an ileo-anal anastomosis. You can her prior to your test, because it means she should use the smallest possible tube or catheter to insert the dye.
Many radiologists and surgeons prefer to use a water-based dye material, such as gastrografin, instead of the barium used in a routine barium enema. In the event your pouch does leak, barium can cause problems with irritation of the abdominal cavity.
The test uses a small amount of radiation to take the x-ray pictures. If it is possible that you could be pregnant, let the receptionist or technician know when you arrive.
References
- J-pouch.org: Living with Your J-Pouch
- "Digestive Surgery"; Routine Use of Gastrograffin Enema Prior to the Reversal of a Loop Ileostomy; G. Khair, O. Alhamarneh, et al.; Sep 4, 2007
- "Journal of the American College of Surgeons"; Complications of Construction and Closure of Temporary Loop Ileostomy; O. Kaidar-Person, B. Person, S.D. Wexner; November 2005
- Drugs.com: Gastrografin
- "Clinics in Colon and Rectal Surgery"; Ulcerative Colitis: Complications of Ileoanal Pouches; E. Gorgun and F.H. Remzi; Feb 2004
- "Grainger and Allison's Diagnostic Radiology, 5th ed."; A. Adam, et al., Eds.; 2008
