The Vertical Sleeve Gastrectomy generates weight loss by restricting the amount of food (and therefore calories) that can be eaten by removing 85% or more of the stomach without bypassing the intestines or causing any gastrointestinal malabsorption. It is a purely restrictive operation.
This procedure generates weight loss solely through gastric restriction (reduced stomach volume). The stomach is restricted by stapling and dividing it vertically and removing more than 85% of it. This part of the procedure is not reversible. The stomach that remains is shaped like a very slim banana and measures from 1-5 ounces (30-150cc), depending on the surgeon performing the procedure. The nerves to the stomach and the outlet valve (pylorus) remain intact with the idea of preserving the functions of the stomach while drastically reducing the volume.
By comparison, in a Roux-en-Y Gastric Bypass (RYGB), the stomach is divided, not removed, and the pylorus is excluded. The RYGB stomach can be reconnected (reversed) if necessary. Note that there is no intestinal bypass with this procedure, only stomach reduction.
Advantages of Vertical Sleeve Gastrectomy (VSG):
- Can be converted to Roux-en-Y
- Excellent weight loss
- Improved health
- Good short term results
Disadvantages of Vertical Sleeve Gastrectomy (VSG):
- Disruption of staple line can lead to leakage or serious infection
- Possible obstruction
- Unknown long term success since studies are less than 5 years old