Sphincterography Sphincterography is an x-ray to evaluate voluntary muscle strength and relaxation. Sphincterography uses a flexible balloon connected to a bag of liquid barium. The pressure inside the balloon is equal to the height of the barium bag above the balloon. The higher the bag, the higher the balloon pressure. The person lies on his left side and a deflated balloon is inserted into the anal canal and rectum.
Barium fills the balloon.
X-rays are taken while the person squeezes, relaxes, and pushes. These x-rays tell how strong the sphincter is and if it relaxes properly. Defecography Defecography uses x-ray to look at the shape and postion of the rectum as it empties. The anal canal is lubricated and a soft plastic tip is inserted through the anal canal into the rectum. The rectum and anal canal are filled with barium paste and the tip is removed.