The gastric sleeve is currently the most commonly performed operation in bariatric surgery in the US. It has had a rapid rise in popularity, as it is a more technically simple procedure than other procedures such as the gastric bypass or duodenal switch. It was originally performed on patients who were too high-risk to undergo a more complex procedure, but the surgeons realized that these patients were doing very well and did not even need an additional complex procedure! The term "sleeve" refers to the portion of the stomach that remains, and the outer portion of the stomach is removed, leaving a tube-shaped stomach that is much smaller than the original stomach. It is about the size and shape of a banana. No new stomach/intestinal connections are made. This procedure is considered a restrictive procedure, because it restricts the amount of food that a patient can physically eat, since the stomach is smaller. There is a secondary benefit as well, which is that the outer portion of the stomach that is removed is the part of the stomach that makes the hormone ghrelin which stimulates hunger. The loss of this hormone allows our patients to experience less hunger, even as they are eating smaller meals. Because this outer portion of the stomach is removed, the sleeve gastrectomy is not reversible.
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