Before gastric banding is discussed, some background information will be reviewed.
Body fat estimation
Obesity is defined as excess accumulation of body fat that may impair health. A simple and practical, albeit imperfect, method to estimate body fat percentage is the body mass index (BMI). BMI is calculated from an individual's height (in meters [m]) and weight (in kilograms [kg]) as follows: BMI = kg/m2. BMI has its drawbacks, as it does not account for body fat percentage, and it may overestimate or underestimate body fat composition in certain individuals.
Visceral fat (central obesity) has a much stronger correlation with metabolic and cardiovascular diseases. The absolute waist circumference (> 102 cm in men and > 88 cm in women) or waist-hip ratio (> 0.9 for men and > 0.85 for women) are both used as measures of central obesity.
However, BMI has become a standard method of evaluating height to weight ratio in most individuals, and thus, this calculation has become an indicator of obesity. Thus, BMI is classified as follows:
BMI less than 18.5 kg/m 2: Underweight
BMI of 18-24.9 kg/m 2: Normal weight
BMI of 25-29.9 kg/m 2: Overweight
BMI of 30 kg/m 2 or greater: Obese
Obesity, in turn, can be subclassified into 3 categories, as follows:
Class I: BMI 30-34.9 kg/m 2
Class II: BMI 35-39.9 kg/m 2
Class III: BMI ≥ 40kg/m 2
In the last few decades, obesity has gained significance as a worldwide health problem. In 2008, the World Health Organization (WHO) estimated that approximately 1.5 billion adults (age 20 y or older) were overweight, and of this population, 200 million were obese men and 300 million were obese women.  Currently, more than 30% of the US adult population is obese,  which accounts for approximately 72 million obese Americans. 
The morbidity associated with obesity is alarming, with an increased incidence of metabolic syndrome, type 2 diabetes mellitus, hypertension, and dyslipidemia, among many other comorbidities.
The need for safe, efficient, and effective means through which patients are able to lose weight and subsequently maintain an adequate body fat percentage is imperative. In this regard strategies aimed at improving healthy eating habits, exercise, and behavioral modification have been only moderately effective in aiding with moderate weight loss. Nonoperative weight loss therapies have not induced long-term weight loss or a sustainable reduction in comorbidities. 
Surgery has proved to be safe and, so far, is the only method available that can induce and maintain major weight loss. [5, 6, 7, 8, 9] One such procedure for weight loss is gastric banding, an example of which can be seen in the video below. [10, 11]
Gastric banding is a restrictive type of surgery in which a silicone band is placed around the top portion of the stomach. The band generates a small pouch with limited volume which will provide an early and prolonged feeling of satiety; additionally, the band slows the passage of food from the pouch to the lower part of the stomach, thus leading to decreased food intake and subsequent weight loss. [5, 12] This procedure is most commonly done using the laparoscopic minimally invasive approach.
A report by Hutter et al found that laparoscopic adjustable gastric banding has lower risk-adjusted morbidity, readmission, and reoperation/intervention rates than laparoscopic sleeve gastrectomy, laparoscopic Roux-en-Y gastric bypass, and open Roux-en-Y gastric bypass. 
Lap-Band and Realize Adjustable Gastric Band
There are 2 types of adjustable gastric bands approved by the US Food and Drug Administration (FDA), Lap-Band and Realize Band.  The Lap-Band System obtained FDA approval in 2001, of which the latest models are the Lap-Band AP-L and Lap-Band AP-S. These bands have fill volumes of 14 mL and 10 mL, respectively.
The Realize Adjustable Gastric Band obtained FDA approval in 2007; its 2 models are the Realize Band and the newer Realize Band-C. The maximum fill volume for the Realize Band is 9 mL, whereas that for the Realize Band-C is smaller. Both the Realize Bands are "one-size-fits-all"; however, the Realize Band-C has a 14% greater adjustment range than the Realize Band. The Realize Adjustable Gastric Band differentiates itself from the Lap-Band AP series through its sutureless, injection port installation.
Other adjustable gastric bands
Two other adjustable gastric bands are in use outside of the United States, neither of which has FDA approval: Heliogast and Midband. The Midband was the first to market in 2000, and the Heliogast band followed in 2003.
Indications and Contraindications
Indications for laparoscopic adjustable gastric banding (LAGB) include the following:
Individuals with a body mass index (BMI) greater than 40 kg/m 2
Individuals with a BMI between 30 and 40 and who have at least one comorbidity that is associated with obesity
In February 2011, The FDA expanded approval of the Lap-Band system to patients with a BMI between 30 to 40 kg/m2 and one weight-related comorbidity.  Additionally, patients should have attempted, without success, to lose an appropriate amount of weight through supervised dietary changes.
Contraindications to LAGB include the following:
Inflammatory diseases of the gastrointestinal tract (eg, Crohn disease, severe esophagitis)
Cirrhosis, portal hypertension, esophageal or gastric varices
Previous gastric perforation near the site of band placement or gastrostomy
Congenital anomalies of the digestive tract (ie, esophagus, stomach, duodenum, situs inversus, etc)
Severe heart or lung disease
Any condition/disease that presents a contraindication for general anesthesia
Autoimmune connective tissue diseases (eg, systemic lupus erythematosus, scleroderma)
Chronic use of steroids or other immunosuppressant medications
Variations in port placement and positioning should be considered and tailored to the individual surgeon's experience.
Operative equipment used include the following:
One 10-mm trocar
One 15-mm trocar
Three 5-mm trocars
Thirty-degree (30°) scope
Laparoscopic liver retractor
External fixation device for retractor
Laparoscopic grasping forceps
Laparoscopic atraumatic grasping forceps
Laparoscopic cautery hook
Laparoscopic needle holder
Anesthesia and patient positioning are briefly described below.
Laparoscopic adjustable gastric banding is carried out under general anesthesia, with an intubated patient. Patients should have a liquid diet 24 hours before surgery and a minimum of 12 hours of nothing by mouth (NPO) before surgery.
Venous compression boots are applied and all pressure points are padded. The patient is then given prophylactic antibiotic and unfractionated heparin, 5000 international units (IU) subcutaneously (SC), or low–molecular-weight heparin (LMWH) should be initiated within 30 to 120 minutes before surgery. General anesthesia is induced.
The patient is placed on the operating table in the supine position with both arms out or in the lithotomy position, depending on the surgeon’s preference. The patient is secured to the operating table to prevent sliding.
The patient’s abdomen is prepped with 2% chlorhexidine gluconate/70% isopropyl alcohol solution and draped. The surgeon is positioned to the right side or between the patient’s legs (if lithotomy position), and the first assistant is on the patient’s left side. The balloon of the band should be checked before placing it to detect any leak in the system.
Monitoring and Follow-Up
The laparoscopic adjustable gastric banding (LAGB) procedure allows for a 1 night hospital stay if not outpatient treatment.
After band placement, the patient will return for follow-up band adjustment after 4 to 6 weeks. Adjustment is carried out by inflating the band with saline solution through the subdermal access port. A noncoring (Huber) needle should be the only type of needle used.
The band will be adjusted in order to generate an opening small enough that will allow both liquids and solids to go through, but it will impede the passage of large amounts of food. The first fill consists of 3 mL in a male patient and 4 mL in a female patient.
The second adjustment occurs at the postoperative week 8, adding 0.5 to 1 mL fill. Further fills occur at 1- to 2-month intervals in the 0.2 to 0.6 mL range, depending on the subjective degree of restriction that the patient feels.
Educating the patient regarding how much to eat, what type of foods to eat, as well as adequate exercise routines are keys in helping the patient lose weight and achieve an adequate quality of life. [8, 15, 16]
The initial placement technique of the laparoscopic adjustable gastric band (LAGB) was a perigastric one. However, this approach has been implicated in high rates of band prolapse/slippage being reported. [17, 18]
The currently favored approach is referred to as the pars flaccida technique.
Pars Flaccida Technique
The pars flaccida procedure is laparoscopic and is normally carried out using a 4- or 5-port technique. A long Verres needle or a 5-mm optical trocar is introduced in the abdomen just below the costal margin in the left upper quadrant at the midclavicular line, and the abdomen is insufflated. If a Verres needle was used, a 5-mm trocar is placed. The patient is tilted into steep reverse Trendelenburg position.
Placement of trocars
After the left costal margin–midclavicular line trocar is placed, 4 more trocars will be placed under direct vision in the following order:
- A 15-mm trocar 6 fingerbreadths below the xiphoid and 5 cm left of the midline for a 30° optical system; it becomes the site of the access port at completion
- A 5-mm port is placed in the right upper abdomen approximately mirroring the one on the left
- Depending on the liver retractor, a 5-mm trocar is placed in the right anterior axillary line for a Snowden-Pencer Brand Diamond-Flex retractor, or it is placed in the midline just below the sternum for a Nathanson liver retractor to hold the left lobe of the liver
- If the surgeon stands between the patient's legs, a port is placed lateral and below the port in the left upper abdomen; if the surgeon is positioned to the right of the patient, a 10-mm port is placed between the right upper abdomen trocar and the 15-mm trocar
The dissection begins at the angle of His with release of the gastrophrenic attachments. Subsequently, a window is created in the pars flaccida of the gastrohepatic ligament.
Where the crus meets the retroperitoneal fat, a small opening is made, and dissection at the right crus is performed to create a retrogastric tunnel.
An Endo-Grasp Roticulator or an articulating dissector is passed gently into the retrogastric tunnel under direct vision. The instrument is then curved, and its tip is visualized in the dissection area of the gastrophrenic attachments.
The band is passed through the 15 mm port into the abdomen. This technique is different depending on the band used: (1) The Realize Adjustable Gastric Band is passed through the posterior tunnel by hooking a preattached Ethibond suture onto the endoscopic dissector or (2) for the Lap-Band, the end of the tubing is passed behind the stomach, and the band is locked in placed upon itself. The band is to be oriented with the balloon facing the stomach wall. 
The fundus of the stomach is then imbricated over the band with 3 gastrogastric nonabsorbable sutures.
Exteriorization of tubing
The tubing is exteriorized using the 15-mm trocar and connected to a port. The band's injection port requires an approximately 3 × 3-cm area of anterior rectus muscle fascia to be cleared off. The balloon of the band must be totally evacuated of all air once the system of the tubing and port are intact. For the Realize Band, the injection port is connected to the port applier, and the unit is applied against the fascia and fired using the trigger. For the Lap-Band, the port is fixed with 4 stitches to the abdominal fascia.
The liver retractor and the trocars are removed, and incisions are closed in standard fashion.
The following is a video demonstrating LAGB using the Realize Band.
The total estimated complication rate for laparoscopic adjustable gastric band (LAGB) procedures is 11%. Other complications and their frequency include the following:
Mortality rate: 0.05%
Access port problems: 0.11-3.0%
Band erosion: 0.2-2% 
Band slippage: 3.1-8.1%
Esophageal dilatation: 6.6-10%
Table 1. Band Slippage Classification (Open Table in a new window)
|I||Anterior slip||Downward migration of the band||Insufficient anterior fixation||Surgical|
|II||Posterior slip||Posterior stomach wall herniates through band||Perigastric approach||Surgical|
|III||Pouch enlargement||Pouch dilatation||Tight band or overeating||Band deflation, patient reeducation|
|IV||Immediate postoperative prolapse||Band placed too low on stomach||Inappropriate low band placement||Surgical|
|V||Type I or II accompanied by gastric necrosis||Band slip with pouch ischemia||Acute pouch dilatation||Surgical|
A retrospective study by Wise et al indicated that African American race and preoperative diabetes mellitus are independent risk factors for impairment of excess weight loss in patients over age 50 years who undergo LAGB. The study involved 117 patients over age 50 years who were treated with LAGB, with multivariate linear regression analysis finding that diabetes mellitus and African American race were independent risk factors for impaired excess weight loss at 6 months following surgery. However, only diabetes mellitus was a risk factor at 1 year postoperatively. 
A study by Fournier et al indicated that when LAGB fails, laparoscopic conversion of patients to a Roux-en-Y gastric bypass is feasible and effective. The revision surgery led to weight-loss results over a 10-year follow-up period that were comparable to those for primary Roux-en-Y procedures. The study, which involved 642 patients, also found that the complication rate did not differ between 1- and 2-step bypass operations.