Radiographic examination of the pouch, by pouchography, CT imaging, and/or 111In-labeled leukocyte scintigraphy, is necessary before closure of the ileostomy to exclude postoperative complications. Kremers et al. advocate studying the pouch by means of a 16 to 20F Foley catheter introduced through the anus. Barium is administered under fluoroscopic guidance and anteroposterior, lateral, and oblique views are obtained in full distention. These authors advocate the use of barium rather than water-soluble contrast medium because barium permits detection of smaller leaks. Additional views are then obtained after catheter removal and spontaneous evacuation of the reservoir to identify leakage, which may not be identified on the filled films, and to evaluate the emptying function of the reservoir. On the other hand, Thoeni et al. advocate antegrade filling of the pouch via the ileostomy, since they feel that this technique better distends the pouch. Thoeni et al. also suggest that CT imaging should be the initial examination; if an abscess is identified then, no other radiographic examination need be performed.
On pouchography, the normal S pouch has a globular appearance with an efferent limb. The J pouch characteristically has a raphe corresponding to the suture lines between the two segments of the pouch. J pouches can vary in size, shape, and pattern of external impressions. In most patients, spiral folds run from the main portion of the pouch to the pectinate line. A lucency resembling a polyp may be identified at the lower edge of the interpouch suture. An impression from the mesentery is another variant that may be confused with a mass.
“radiology images of S pouch.” Contrast examination via the rectum after IPAA shows the normal globular appearance of the S pouch (A) in the anteroposterior projection and (B) in the lateral projection.
radiology images of J pouch. (A) Contrast examination via the rectum after IPAA demonstrates the normal appearance of the J pouch in the anteroposterior projection with the characteristic raphe corresponding to the suture line. (B) Lateral view.