Laparoscopic Gastric bypass surgery Roux-en-Y:
The most common gastric bypass surgery is a Roux-en- Y gastric bypass.
In a Roux-en-Y gastric bypass, the stomach is made smaller by creating a small pouch at the top of the stomach using surgical staples or a plastic band. The smaller stomach is connected directly to the middle portion of the small intestine (jejunum), bypassing the rest of the stomach and the upper portion of the small intestine (duodenum).

This procedure can be done by making a large incision in the abdomen (an open procedure) or by making a small incision and using small instruments and a camera to guide the surgery - laparoscopic approach. You will probably stay in the hospital a shorter time and recover more quickly after laparoscopy, compared to open surgery. The biggest benefit of laparoscopic surgery is reduced pain. You will also have smaller scars and a lower risk of developing hernias.

Laparoscopic Adjustable Gastric Banding (LAGB)
LAGB or lap banding is a surgery that uses an adjustable band around the opening to the stomach. This reduces the amount of food that you can eat at one time. Lap banding is done through small incisions, with a laparoscope. The band can be adjusted after surgery, allowing you to eat more or less food. This is done by using a needle to add or remove fluid from a port (a small container under the skin that is connected to the band). Adding fluid makes your stomach smaller, which may help you to lose more weight. Lap banding is a popular choice because it is relatively simple to perform, can be adjusted or removed, and has a low risk of serious complications immediately after surgery.

However, weight loss with the lap band depends on your ability to follow the program closely. You will need to prepare nutritious meals that "work with" the band, not against it. For example, the lap band will not work well if you eat or drink a large amount of liquid calories (like ice cream).

 Weight loss ranges from 45 to 75 percent after two years. As an example, a person who is 120 pounds overweight could expect to lose approximately 54 to 90 pounds in the two years after lap banding.

Laparoscopic Sleeve Gastrectomy
Gastric sleeve, also known as sleeve gastrectomy, is a surgery that reduces the size of the stomach and makes it into a narrow tube. The new stomach is much smaller and produces less of the hormone (ghrelin) that causes hunger, helping you feel satisfied with less food. Sleeve gastrectomy is safer than gastric bypass because the intestines are not rearranged, and there is less chance of malnutrition.

It also appears to control hunger better than lap banding. It might be safer than the lap banding because no foreign materials are used.
The gastric sleeve has a good success rate, and people lose an average of 33 percent of their excess body weight in the first year. For a person who is 120 pounds overweight, this would mean losing about 40 pounds in the first year.