Histologic study of tissue reaction to the gastric band: Does it contribute to the problem of band erosion?

Background: One of the major complications of gastric banding is intragastric migration of the band. The frequency ranges from 0.5% to 3.8%, and removal of the band is always required. We undertook a prospective study with the aim to determine the reasons for this significant complication in bariatric surgery. Methods: 480 morbidly obese patients underwent adjustable gastric banding in our Surgical Department, from February 1998 to October 2005. 31 of them were reoperated for different surgical problems, at an average time of 39 months after the bariatric procedure. During the reoperation, some fragments of fibro-adipose tissue in close contact with the band were removed. They were examined, focusing on the following parameters: acute and chronic inflammation, fibrosclerosis, and foreign body granulomatous reaction. Results: Histological assessment showed the presence of acute and chronic inflammation, generally of mild and medium grade; fibrosclerosis was present mostly in a severe form, indicating a biological periprosthesic wall that separates and protects the gastric wall from the band; no cases of foreign body reaction were observed, nor were silicone inclusions found inside the inflammatory cells. Conclusion: The histologic changes of periprosthesic tissue do not appear to account for endoluminal migration of the gastric band. Thus, band erosion could have a closer correlation with other causes, such as infection of the band or intraoperative surgical damage, possibly due to direct mechanical action or to the thermal effect of the electric scalpel.