Unsure which operation you should be looking for?
This video is for you
Understanding
Bariatric Surgery
This is a good overview and particularly demonstrates the Gastric Sleeve.
Warning: Contains actual surgery scenes
This video demonstrates the surgical steps in a Single Anastamosis (Mini) Gastric Bypass Operation
Warning: Contains actual surgery scenes
An Animation of the "Mini" Gastric Bypass.
aka. One or Single Anastamosis Bypass
This video demonstrates the surgical steps in a Roux en Y Gastric Bypass Operation
Warning: Contains actual surgery scenes
An Animation of a Roux Y Gastric Bypass
These are very useful for understanding the role for Bariatric Surgery