Obesity is caused by a combination of genetics, environmental issues, and behavioral factors. [1, 2] Consumption of high-calorie foods, consumption of too much food, and a sedentary lifestyle all work together to create this condition. Obesity is associated with the development of diabetes mellitus, hypertension, dyslipidemia, arthritis, sleep apnea, cholelithiasis, cardiovascular disease, and cancer.
More than 100 million Americans (65% of the adult population) are overweight.  Obesity is the second-leading cause of preventable death in the United States, after smoking. Obesity-related diseases account for 400,000 premature deaths each year. 
Obesity can be treated medically and surgically. Medical treatment for obesity is difficult, because the amount of weight lost is small and patients tend to regain most of the weight. A 2010 prospective, randomized controlled trial in 50 adolescents demonstrated that a greater percentage of patients achieved a loss of 50% of excess weight with laparoscopic gastric banding than with lifestyle intervention. 
Operations that are designed to cause significant and long-lasting weight loss in patients who are severely obese are forms of bariatric surgery, a term derived from the Greek words baros ("weight") and iatrikos ("pertaining to a physician"). Laparoscopic gastric banding, described here, is one such surgical procedure; this procedure falls under the subcategory of restrictive bariatric surgery. Another form of bariatric surgery is gastric bypass (see Laparoscopic Gastric Bypass).
Body mass index (BMI) describes relative weight for height and correlates significantly with an individual’s total body fat.  BMI is based on height and weight and applies to adults of both sexes. It is calculated in either of two ways, as follows [1, 4] :
BMI = weight (kg)/height (m2)
BMI = weight (lb)/height (sq in.)
In 1991, the National Institutes of Health (NIH) provided a consensus statement for selecting bariatric surgery candidates.  Patients were considered candidates for surgery if they met one of the following criteria:
Body mass index (BMI) >40
BMI of 35-40 plus one of the following obesity-associated comorbidities: severe diabetes mellitus, pickwickian syndrome, obesity-related cardiomyopathy, severe sleep apnea, or osteoarthritis interfering with lifestyle
To be candidates for bariatric surgery, patients should have attempted, without success, to lose an appropriate amount of weight through supervised diet changes.  Patients must also comply with postoperative diet and exercise.
In 2008, the Society of American Gastrointestinal and Endoscopic Surgeons issued guidelines for the clinical application of laparoscopic bariatric surgery.  The SAGES guidelines noted that well-selected patients who have a BMI higher than 60 or are older than 60 years may benefit from laparoscopic bariatric surgery by experienced surgeons and that adolescents may also benefit from such surgery.
In February 2011, the US Food and Drug Administration (FDA) expanded the use of the Lap-Band System (Apollo Endosurgery, Austin, TX) for patients with a BMI of 30-34 and having any obesity-associated comorbidities.
Contraindications for laparoscopic gastric banding include the following:
History of substance abuse
An active major psychiatric disorder
End-stage organ disease (eg, cardiac, hepatic, or pulmonary)
Stomach or intestinal disorder or infection
Inability or unwillingness to follow dietary recommendations
General anesthesia is required for this procedure.
Laparoscopic gastric banding requires an instrument tray that includes the following:
Laparoscopic banding device
Different length and sizes of trocars
Nathanson liver retractor
The patient is positioned comfortably in a semilithotomy position. The surgeon stands between the patient’s legs or on the patient’s right side, and the first assistant stands on the left side of the patient and holds the camera. The surgeon should be standing comfortably with arms and elbows in an abducted position. Before starting the procedure, the surgeon should adjust the monitors to eye level.
Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient have been formulated by the American Society for Metabolic and Bariatric Surgery. 
Laparoscopic banding procedure
The abdomen is entered under direct visualization by placing a 5-mm port with a 30º lens. A 15-mm trocar and a 5-mm trocar are placed as working points. A 5-mm first assistant port and a Nathanson retractor to elevate the left lateral segment of liver are placed (see the video below). The trocars should be positioned at least a fist-length apart; this allows the surgeon to use both hands comfortably.
The dissection begins with a gentle blunt release of gastrophrenic attachments at the angle of His. The gastrohepatic window is entered, and dissection at the right crus is performed to create a retrogastric tunnel.
A band of appropriate size is introduced through the 15-mm trocar. Before insertion, the balloon of the device should be checked to avoid placing a defective band. When the band is in place, the tubing is grasped by the grasper, retracted through the retrogastric tunnel, and locked into position anteriorly. Three gastrogastric sutures are placed to create a gastrogastric plication around the band and hold it in position. An additional gastrogastric suture is placed below the band.
The tubing is exteriorized and connected to a port, which is secured to the abdominal wall fascia.
The Nathanson retractor and the trocars are removed under direct visualization, and incisions are closed in standard fashion.
A preoperative low-calorie diet seems to help decrease the size of the liver. Care should be taken to ensure that the patient is kept well hydrated.
Complications of laparoscopic gastric banding include the following:
Perforation of stomach
Injury to spleen
Mechanical device failure
Mortality of 0.08%
In a retrospective review of 156 patients who underwent laparoscopic adjustable gastric banding over a 4-year period, Papadimitriou et al reported an overall complication rate of 15.4% and a major complication rate of 3.2%.  The authors noted that the procedure carried certain complications even when performed by a surgeon experienced in laparoscopic surgery. Subset analysis suggested that the learning curve for laparoscopic gastric banding is at least 50 procedures.