A retrospective review by Brown et al [52] published in 1990 compared CT to fluoroscopic examination of patients with IPAA. Some of the fluoroscopic examinations were performed antegrade through the distal limb of the loop ileostomy, whereas others were performed retrograde. In these 18 patients, 10 had infectious symptoms and 8 did not. CT more clearly delineated the site and extent of abscess in 9 patients with infectious symptoms compared with the fluoroscopic studies [52]. However, this study did not evaluate the sensitivity or specificity of each examination, neither did it directly address pouchitis. To our knowledge, there is no recent literature evaluating fluoroscopic contrast enema for the diagnosis of proctitis or pouchitis. MR Enterography Pouchitis can also be evaluated as part of MR enterography. MR enterography is commonly performed with biphasic oral contrast agents that produce low signal intensity on T1-weighted sequences and high signal intensity on T2-weighted sequences because they allow excellent characterization of bowel wall enhancement on IV contrast- enhanced T1-weigheted sequences. These agents include low weight/volume barium solutions, water, polyethylene glycol, and methylcellulose. Patients ingest a large volume of the oral contrast prior to the examination. Administering an antispasmodic drug such as glucagon is useful for reducing motion artifact caused by bowel peristalsis. Both FSE T2-weighted and steady-state free precession T2-weighted sequences are generally performed to compensate for limitations of each in addition to dynamic IV contrast-enhanced sequences. In 28 patients who underwent colectomy with IPAA, Sahi et al [53] compared MR enterography, pouch endoscopy, and biopsy. They found that the presence of 4 or more MR enterography features of inflammation had the best correlation with endoscopic findings (86% sensitivity, 79% specificity, 80% PPV, 85% NPV, and 82% accuracy). Anorectal Disease
Anorectal Disease. A retrospective review by Brown et al [52] published in 1990 compared CT to fluoroscopic examination of patients with IPAA. Some of the fluoroscopic examinations were performed antegrade through the distal limb of the loop ileostomy, whereas others were performed retrograde. In these 18 patients, 10 had infectious symptoms and 8 did not. CT more clearly delineated the site and extent of abscess in 9 patients with infectious symptoms compared with the fluoroscopic studies [52]. However, this study did not evaluate the sensitivity or specificity of each examination, neither did it directly address pouchitis. To our knowledge, there is no recent literature evaluating fluoroscopic contrast enema for the diagnosis of proctitis or pouchitis. MR Enterography Pouchitis can also be evaluated as part of MR enterography. MR enterography is commonly performed with biphasic oral contrast agents that produce low signal intensity on T1-weighted sequences and high signal intensity on T2-weighted sequences because they allow excellent characterization of bowel wall enhancement on IV contrast- enhanced T1-weigheted sequences. These agents include low weight/volume barium solutions, water, polyethylene glycol, and methylcellulose. Patients ingest a large volume of the oral contrast prior to the examination. Administering an antispasmodic drug such as glucagon is useful for reducing motion artifact caused by bowel peristalsis. Both FSE T2-weighted and steady-state free precession T2-weighted sequences are generally performed to compensate for limitations of each in addition to dynamic IV contrast-enhanced sequences. In 28 patients who underwent colectomy with IPAA, Sahi et al [53] compared MR enterography, pouch endoscopy, and biopsy. They found that the presence of 4 or more MR enterography features of inflammation had the best correlation with endoscopic findings (86% sensitivity, 79% specificity, 80% PPV, 85% NPV, and 82% accuracy). Anorectal Disease