Pouch volume and pouch migration after Roux-en-Y gastric bypass: a comparison of gastroscopy and 3 D-CT volumetry: is there a "migration crisis"?

Background: Roux-en-Y gastric bypass (RYGB) is the second most frequently performed bariatric procedure worldwide. While pouch migration is a common phenomenon after sleeve gastrectomy, it has hardly been documented after RYGB so far.

Objectives: The aim of this study was to correlate the diagnostic performance of gastroscopy of the gastroesophageal junction with 3-dimensional computed tomography (CT) during postoperative care of patients revised due to weight regain after RYGB, with particular attention to intrathoracic pouch migration (ITM) and pouch volume.

Setting: University Hospital Setting, Austria.

Methods: Thirty RYGB patients that were revised owing to weight regain (median age 37.5 yr) before December 2017 were included in this prospective study. CT findings were correlated with gastroscopy regarding pouch size and ITM. Pouch distention was achieved with both oral contrast and effervescent granules. All patients had CT and gastroscopy on the same day. In addition, patients were evaluated for reflux disease based on clinical history.

Results: ITM was found in 20 of 30 (66.7%) patients in CT, whereas gastroscopy did not correctly identify any herniation. In 16 of 28 (57.1%) patients pouch measurements at gastroscopy and CT showed a difference <40%. In 2 patients, pouch distention was not sufficient for CT volumetry. The intraclass correlation coefficient proved to be .594. Symptomatic reflux was present in 10 of 30 (33.3%) patients, 5 of whom had ITM.

Conclusion: ITM is an underreported finding after revised RYGB and missed in gastroscopy. In terms of pouch volume, 3-dimensional-CT volumetry demonstrated only moderate agreement with gastroscopy.