Radiological diagnosis of internal hernia after Roux-en-Y gastric bypass

Background: Internal hernia is a known complication of laparoscopic Roux-en-Y gastric bypass (LRYGBP). Preoperative diagnosis may be difficult on the basis of history and physical examination. CT scanning is often performed as a diagnostic tool for patients with symptoms after LRYGBP but is often read by the radiologist as non-specific or normal. Preoperative review of the study by the bariatric surgeon who is familiar with the neo-anatomy can identify the internal hernia and its location. Methods: We retrospectively reviewed our first 185 patients undergoing LRYGBP to identify all patients who developed an internal hernia. The patient's symptoms, physical findings and CT scans were reviewed. Time to presentation with the internal hernia was noted. Radiological interpretation of the scans was recorded, as well as the bariatric surgeon's preoperative impression after review of the scans. Results: In our initial experience of 185 patients undergoing LRYGBP, 5 patients presented at various times in their postoperative course with an internal hernia, for an incidence of 2.7%. All patients underwent preoperative CT scanning. Radiologist interpretation of the scans identified one internal hernia of the 5 preoperatively and was suggestive in another. Preoperative review of the scans by the bariatric surgeon was not only highly suggestive of the diagnosis, but of the location as well, in all 5 cases. Conclusion: Preoperative diagnosis of an internal hernia in patients after LRYGBP is often difficult. CT scanning has been found to be a very helpful diagnostic tool, especially when reviewed preoperatively by the bariatric surgeon.