Pouch Enlargement: myth or reality? Impressions from Serial Upper Gastrointestinal Series in Silicone Gastric Banding Patients

Does significant pouch enlargement in measured pouches occur with the passage of time? In order to determine an answer to this question, 163 silicone gastric banding (SGB) patients, both non-adjustable and stomaadjustable, with multiple follow-up gastrointestinal (GI) series were reviewed. All SGB patients have a baseline GI series of their measured 25 ml pouch prior to discharge. These baseline X-rays were compared with subsequent GI series performed 12 or more months after the procedure. Spinal vertebrae in the GI series were measured and compared to the baseline X-rays to assure that pouch measurement results of the follow-up and baseline pouches were comparable and not distorted by different X-ray techniques. If any differences in the techniques were found, the estimated pouch volume was adjusted. For the purpose of this report, significant pouch enlargement was considered to be greater than 150%. Follow-up GI series were performed in 1986 (n = 74, 85% without significant change), 1988 (n = 97, 97% without significant change), 1990 (n = 31, 97% without significant change) and 1991 (n = 28, 100% without significant change). Half of the very large pouches occurred in the first 30 SGB patients, when pouch calibration technique was still in the developmental stage. Follow-up X-rays performed in 1986 and 1988 in 31 patients revealed only one enlargement greater than 100%. Of the seven patients who had three follow-up X-rays, none showed significant enlargement. These results would seem to indicate that some enlargement will occur with time, but in most SGB patients it is not excessive and does not affect the results of the operation. The use of baseline and sequential follow-up GI series is at the present time the only effective method to monitor pouch enlargement.