Utility of contrast enema for detecting anastomotic strictures after total proctocolectomy and ileal pouch-anal anastomosis.

OBJECTIVE

The purpose of our study was to determine the utility of contrast enemas for detecting clinically relevant anastomotic strictures after total proctocolectomy and ileal pouch-anal anastomosis and to facilitate management by defining a critical anastomotic caliber at or below which obstruction is likely to develop after ileostomy closure.

MATERIALS AND

METHODS

Our radiology database revealed 42 patients with contrast enemas after total proctocolectomy and ileal pouch-anal anastomosis who fulfilled our exclusion criteria. The initial postoperative contrast enemas were reviewed blindly to determine the diameter of the ileoanal anastomosis. The diagnosis of a stricture was made only if the patient had signs of intestinal obstruction after ileostomy closure with confirmation on follow-up contrast enema or sigmoidoscopy and clinical improvement after anastomotic dilatation. The data were then correlated to determine if there was a critical anastomotic caliber at or below which such strictures were likely to develop. Using this threshold value, the sensitivity and specificity of routine contrast enemas for detecting clinically relevant anastomotic strictures were then determined.

RESULTS

Six (14%) of the 42 patients who underwent total proctocolectomy and ileal pouch-anal anastomosis had strictures at the ileoanal anastomosis on contrast enemas. The mean diameter of the anastomosis was 5.8 mm in the six patients with anastomotic strictures versus 15 mm in the 36 patients without strictures (p = 0.0002). If an anastomotic diameter of 8 mm is defined as the critical caliber at or below which clinically relevant strictures are present, the sensitivity of contrast enemas for detecting strictures at the ileoanal anastomosis was 100% (six of six patients) and the specificity was 92% (33 of 36 patients).

CONCLUSION

Routine contrast enema after total proctocolectomy and ileal pouch-anal anastomosis is a sensitive test for detecting clinically relevant strictures at the ileoanal anastomosis when an anastomotic diameter of 8 mm or less is used as the threshold value for diagnosing these strictures. Such patients may need dilatation procedures to decrease the risk of anastomotic obstruction after ileostomy closure.