Bariatric surgery is the most effective treatment for obesity, but it is cost-prohibitive on both national and individual scale. Access to this surgery is thus limited as only few centers and surgeons are doing this surgery on a regular basis, and less than 1% of the eligible population receives bariatric surgery as the rest cannot afford the expensive treatment and also do not come forward as they fear an irreversible procedure. In the last decade, endoscopic therapies for obesity have emerged as an alternative to bariatric surgery particularly after the advent of natural orifice transluminal endoscopic surgery (NOTES). Some of these new treatment modalities have also received the Food and Drug Administration (FDA) approval. Endoluminal surgery by definition is a surgery that requires placement or removal of some device in the stomach and bowel with the help of a flexible endoscope for the management of weight loss or treatment of glucose intolerance. There are issues in operating an obese patient and that include a high incidence of morbidity and up to 2% mortality which is not acceptable. Patient may want nonsurgical and reversible therapy and that in bariatric surgery is not possible. Surgeons at many a times are at a crossroad in a very high-risk patient as he is not able to answer whether it is worth taking so much risk and many times he ends up with excess weight loss (EWL) or malnutrition. Thus, an alternate procedure was always needed that would offer more durable weight loss compared to diet and pharmacotherapy alone but less invasive than the bariatric surgical interventions and endoluminal bariatric surgery has emerged as an alternative therapy of choice for such patients both as primary and secondary therapy of obesity.
Although the endoluminal and transgastric procedures in the treatment of obesity are still in its infancy, but will eventually provide valuable approaches to various group of patients with more effectiveness compared to lifestyle modifications alone or medications.1 The American Society of Gastrointestinal Endoscopy (ASGE) in its recent position statement has also endorsed that endoluminal bariatric therapy in conjunction with multidisciplinary weight loss program may be accepted for long-term weight treatment.2
Presently, the endoscopic bariatric procedures are being used in one of the following indications where it has shown beneficial results:
- An early pre-emptive intervention in patients who are in early stage of obesity and do not qualify for bariatric surgery
- Bridge therapy to reduce operative risk for various bariatric and nonbariatric surgeries in a severely obese patient
- Primary metabolic treatment, these procedures focus on treating the co-morbid conditions associated with obesity
- Primary bariatric treatment in the traditional surgical group and with efficacy and result that may match the conventional bariatric surgery
- Finally, endoluminal therapy probably would be used most commonly in revisional surgery for patient regaining weight after bariatric surgery.
ENDOSCOPIC BARIATRIC DEVICES AND THERAPIES
The endoluminal devices and therapies presently being used differ significantly in size, shape, duration of use, and also on their mechanism of producing the desired effect. Most of the devices are based on the same principles, aims, and objectives that are followed in bariatric surgery to achieve the desired results. The main mechanisms by which these devices become effective are by delaying gastric emptying, reducing the gastric volume, by various types of restrictive procedures to prevent absorption of nutrients, and finally by inducing malabsorption with endoscopic bypass, a mechanism similar to Roux-en-Y bypass surgery.
The endoscopic treatment options that are currently most popular can be divided into following categories with various newer procedures that are being added to this list of procedures (Figs. 1A to D).
- Space occupying devices: Intragastric balloon (IGB) and similar other device working on the principle of IGB
- Restrictive procedures: Various types of endoscopic suturing and stapling procedures attempting to restrict the food intake by reducing the capacity and size of stomach
- Bypass liners
- Electrical stimulation
- Aspiration therapy
- Newer emerging therapies.
Although most of the endoscopically placed devices and procedures seem to be temporary, some of these are also permanent and irreversible.
The idea of using an endoscopically placed intragastric device for control of obesity was first described in 1982 and since then various devices have been tested to achieve weight reduction in obese patients.3–5The intragastric devices are based on the physiology of reducing the intragastric capacity and in addition to mechanical restriction, reduction in hunger due to hormonal modulation also leads to decreased energy intake.6 One more mechanism of action of these IGBs is to alter gastric motility and delaying gastric emptying.
Randomized control trial of IGB has demonstrated an increase in retained gastric contents 2 hours after radiological meal ingestion in the balloon group compared with a control group 8 weeks after IGB placement.7 The Garren-Edwards Gastric Bubble (GERB), was approved for use by FDA in 1985 as an adjunct to diet, exercise, and behavioral therapy.
The GERB (American Edwards Laboratories California) was a polyurethane cylindrical device, with a removable air insufflation catheter. The Garren-Edwards balloon was used in United States till 1988 but controlled studies subsequently reported that it was not successful in inducing more weight loss than diet or behavioral modification alone.8 Moreover, several complications were reported that included gastric erosions, gastric ulcers, small bowel obstruction, Mallory-Weiss tear, and esophageal laceration.9 The Garren-Edwards balloon was later discontinued and is no longer used.
Several modifications of such balloons were used in subsequent years. It was presumed that the small volume of air used in bubble was responsible for failure to achieve the desired results, and material used in the balloons was the causative factor for the complications. The Taylor IGB (Dunlop Limited, England) and the Ballobes IGB (DOT ABS, Denmark) were later attempted endoscopically; while the Taylor balloon was inflated with 550 mL of saline, the Ballobes balloon was inflated with approximately 475 mL of atmospheric air.
In the recent past, many newer versions of the balloons have emerged and have gained popularity as most of these are based on the fundamental design criteria laid down by 75 international experts in 1987 in Tarpon Springs.10 Three IGBs, the Orbera (Apollo Endosurgery Austin, Tx), the ReShape Integrated Dual Balloon System (ReShape Medical, San Clemente, CA), and the Obalon (Obalon Therapeutics, Carlsbad, CA) have been approved for use in United States by the US FDA (Fig. 2), and two more, the Spatz Balloon (Spatz FGIA, Great Neck, NY) and Elipse Balloon (Allurion Technologies, Wellesley, MA) are in the process of getting FDA approval.
Fluid-filled Single Balloons
These IGBs are fluid-filled balloon made of silicone and sit in stomach like a bezoar. As per FDA recommendation, it is required to remove the balloons after 6 months of implantation.11 The balloons are mostly single spherical or ovular shape that can typically be filled with saline from 500 mL to 750 mL (range 250–950 mL) and of the dual balloon each balloon can be filled up to 450 mL (Fig. 2).
The most widely used fluid filled balloon is Orbera, which was originally known as Bioenteric Intragastric Balloon (BIB, Allergen, Irving, California) (Fig. 3).
The balloon is deployed into the stomach either under conscious sedation or short general anesthesia. A predeployment upper gastrointestinal (GI) endoscopy is mandatory to rule out neoplasia, gastric or esophageal lesions and ulcers, previous gastric surgery, and large hiatal hernia before placing the balloon. The deflated balloon is properly lubricated and passed into the stomach alongside a standard upper endoscope or it can also be introduced directly along with the filling catheter down the esophagus into the stomach. Once inside the stomach, its position is verified endoscopically and thereafter it is filled with the desired amount of normal saline, usually 400–700 mL, with 2–10 mL of methylene blue solution added.
In case of accidental rupture of balloon, the methylene blue gets absorbed and excreted in urine giving a greenish blue color to the urine.12 Majority of recent studies have found gastric balloon to be well tolerated and effective with very minimal side effects. Minor complications include nausea, vomiting, and pain in the first 72 hours but mostly resolve spontaneously. The more serious complications although rare include esophagogastric erosions and gastric ulcer,13 device rupture, and migration causing bowel obstruction and perforation which can be life-threatening.14
Most of the studies have found an EWL at the time of device removal in the range of 30–50%,15 but there are few studies that have reported weight regain on a long-term follow up after balloon removal.16
There had been attempts at placing successive balloons but the FDA has not approved such placement of successive implants.
Reshape Duo: Fluid-filled Dual Balloon
The Reshape procedure involves placing two intragastric equal sized silicon balloons that are attached to each other by a flexible tube (Reshape Medical Inc, San Clemente, CA). The two balloons can hold a combined 900 mL of saline and are placed endoscopically like the Orbera balloon but has an added advantage of protection against migration in the case of accidental deflation or rupture of one of the balloons.
Results of the largest randomized trial involving 326 patients, the REDUCE Pivotal Trial, where the device was removed at 24 weeks, have been very encouraging with a mean % EWL of 25.1% versus 11.3% in the sham group.17 The major complications observed in this trial was gastric ulcer (35%) even in patients who were on proton pump inhibitors followed by the device deflation that occurred in 6% of patients but no report of any migration.
The Spatz Adjustable Balloon
To avoid the undesirable complications of nausea and vomiting, an adjustable fluid-filled balloon Spatz (Spatz Medical, Great Neck, New York) has been introduced but presently we have limited data available on its safety and efficacy. The balloon is placed endoscopically but needs to be fixed to the tip of the scope and has an inflation tube attached to it that remains in the stomach and with the help of the tube, the balloon volume can be adjusted after taking the tube out endoscopically. The adjustable tube also helps easy withdrawal of the balloon when required. Although the balloon is not FDA approved, it is approved for use in Europe (Fig. 4). Results of one of the big study involving 73 patients has shown an EWL of 45.7% with reports of three cases needing surgical extraction of migrated and impacted inflation catheter.18 The balloon is designed to be kept in place for 12 months.
Obalon: Gas-filled Balloon
This is the first version of swallowable implantations device apart from the introduction of polymer pill. The Obalon Gastric balloon (OGB), Obalon Therapeutics, Carlsbad, California, comes as a gelatin capsule that can be swallowed and the capsule has a thin attached catheter that extrudes out of mouth to help inflate the balloon with nitrogen gas with the help of an inflation device. Although the balloon has a capacity of about 250 mL but up to three balloons placement have been reported in the literature with the balloon being removed endoscopically at 12 weeks. In the pilot study in Europe involving 17 patients, an EWL of 36% has been reported with no reported complications.19
Self-degradable Balloon Elipse
The Elipse balloon (Alturion Technologies, Wellesley, Massachusetts) is made of a thin film and is enclosed within a capsule. The capsule is swallowed under guidance of image intensifier and once it is in the stomach it can be distended up to 550 mL with a thin cord that is attached to the balloon. The balloon life is approximately 4 months and thereafter it ruptures on its own, gets completely deflated and passes down the GI tract. In a pilot study conducted on 8 patients, an EWL of 12.4% was observed.20
The polymer pill developed by BaroNova Therapeutics, Inc (Foster city, California) also works on the principle of space occupying devices. The pill is ingested or may also be delivered endoscopically and expands, and takes up the space in the stomach. It degrades and passes spontaneously after a week. The pill can be taken regularly and even the intervals can be titrated depending on the response.21
Transpyloric Shuttle and SatiSphere
The transpyloric shuttle (TPS BaroNova Inc, Goleta, California), a dumbbell-shaped device consists of one larger ball of 56 mm diameter connected to a smaller cylindrical bulb. The device is placed endoscopically over a tube and once developed the smaller sphere having weight enters the duodenal bulb and the larger bulb gets pulled causing intermittent obstruction and thus delaying gastric emptying. While the new generation TPS are under randomized trial in United States, the previous study involving 20 participants have shown good results with 25% EWL at 3 months and 41% at 6 months of the device placement.22 A device called SatiSphere that works on the principle of delaying the transit of food both in the distal stomach and the duodenum has multiple mesh spheres that are attached to a wire that is passed into the duodenum endoscopically (Fig. 5).
The aspiration of gastric contents with the help of a specially designed gastrostomy tube called A-tube and the Aspire Assist device (Aspire Bariatrics, King of Prussia, Pennsylvania) is based on the principle of removing 30% of each meal approximately 20 minutes after consumption of the meal (Fig. 6). The technique although surgical is simple like percutaneous gastrostomy and is FDA approved as it has been reported to be safe with minimum morbidity and complication with results of mean EWL of 40.8 % + 19.8% in two large series.23,24
The technique of placement of A-tube is similar to percutaneous endoscopic gastrostomy and on an average 80% of the weight loss could be achieved in the series mentioned here but the patient was advised to take food slowly and chew it properly and was also advised to take sufficient water with meals.
The most common and minor complication reported in the US pivotal trial included peristomal granulation tissue formation and irritation, nausea, abdominal pain, and bacterial and fungal infection of the A-tube.25
These procedures are mostly based on the principle of modifying gastric anatomy and achieving the low volume stomach by endoscopic means and thus doing gastroplasty endoscopically. The two procedures that are more popular and currently being used are primary obesity surgery endoluminal (POSE) that uses a device called incision less. Operating platform (USGI Medical, San Clemente, CA) and the endoscopic sleeve gastroplasty (ESG) are done with a device called Apollo OverStitch (Apollo Endosurgery, Austin, Texas). Both the devices are FDA approved. There are various other devices and techniques that are also being used to achieve restriction of food intake but are not very popular with less favorable outcome and these are transoral gastroplasty using the TOGA system (Satiety Inc, Palo Alto, CA) and articulating circular endoscopic (ACE) stapling procedure.
Whereas the TOGA system uses a device to suck tissue in the jaw and place full thickness staples along the lesser curvature of the stomach like vertical banded gastroplasty, the ACE stapler uses an endoscopic ACE stapler (Boston Scientific Corporation; Natick, MA) and as the stapler has complete retroflexion movement it is used to create eight plications in the fundus and two in the pyloric antrum to create gastroplasty and small stomach.
Endoscopic Sleeve Gastroplasty
The Apollo OverStitch is a double channel device and is FDA approved for tissue apposition and is used to place full thickness stitches along the greater curvature of stomach to achieve the shape and size of the stomach similar to sleeve gastrectomy (Fig. 7). The device is fixed to the end of the endoscope and has a curved needle driver to take sutures. With the help of device, closely placed sutures are placed from the pyloric antrum to the esogastric junction creating a neostomach (Fig. 8). One of the largest published series has reported a total body weight loss of 16.2% + 0.7%.26
A specially designed device, the Incisionless Operating Platform is used to create 8 or 10 full thickness plications in the fundus of the stomach. The device is a 54 Fr flexible tube having a control handle similar to an endoscope and can be maneuvered in various directions. With the help of an ultra slim scope passed through one of the four channels of the device, the visualization is achieved. The other channels are used to insert the special instruments for grasping (G-Lix) the fundic wall and for placing the tissue anchors (Fig. 9).
Usually, two rows of plication anchors are needed to bring the whole fundus down to the level of gastroesophageal junction to achieve the desired results.27,28 The procedure has undergone a randomized controlled trial in the United States in patients with body mass index (BMI) between 30 kg/m2 and 34.9 kg/m2 and the procedure success rate reported was 99.5% with total weight loss reported to be 4.94% + 7.04% in the active subjects.29
BYPASS LINERS AND SMALL BOWEL DIVERTING THERAPIES
A wide variety of prosthetic devices and incisionless anastomotic procedures have been developed and some of such products are also under development. The bypass liners are various types of tubular prosthesis mostly used to prevent nutrient absorption. Although EndoBarrier gastrointestinal liner is still considered a procedure under investigation but has the great potential for treatment of types 2 diabetes, obese people at risk of diabetes, and also a bridge therapy for patients with severe weight problems.
Duodenojejunal Bypass Liner
EndoBarrier (GI Dynamics, Inc, Lexington, MA) is a device made of ultrathin flexible Teflon Sleeve of 65 cm length that is anchored to the duodenal bulb with a barbed nitinol crown. This extends for about 60 cm into the small bowel and is deployed for duration of 6 months. The sleeve allows food to bypass the duodenum and proximal part of jejunum. The liner is deployed endoscopically in the jejunum with the help of a catheter and self-expanding anchor that gets fixed to the pylorus with 10 sharp barbs projecting from the nitinol crown.
The exclusion of the duodenojejunal nutrients due to the biliary and pancreatic juices flowing outside the sleeve and mixing with chyme only in the distal jejunum is the main mechanism of improvement of glycemic control in patient with diabetes and also weight loss. Over the years, the device is more commonly being used as an endoscopic metabolic procedure rather than a purely bariatric procedure.
The efficacy of gastroduodenal barrier sleeve has been studied extensively and various studies have mentioned the extra weight loss in the range of 30–40%. Although GI bleedings obstruction and pain abdomen has been reported, even serious complications like esophageal perforation and cholangitis are also reported.30 This incidence of cholangitis leading to development of liver abscess was the reason that the multicenter randomized trial in the United States, the ENDO trial, had to be stopped.30
Gastroduodenojejunal Bypass Liner
The gastroduodenojejunal bypass liner sleeve (Valen Tx Endoluminal Bypass, Valen Tx Inc, Hopkins, MN) is yet another tubular fluoropolymer sleeve device that is deployed by a hybrid technique utilizing both endoscopy and laparoscopy. The device is 120 cm long and extends from the stomach to the jejunum and thus stomach, duodenum, and proximal jejunum are bypassed.
There is very few data available in the literature about the efficacy of the sleeve and the only pilot study that involved 12 subjects and lasting 1 year, although reported an EWL of 35.9% but also reported device removal in 2 cases and in 4 out of the 12 candidates the device was seen to be partially detached making it less effective.31
OTHER INVESTIGATIONAL DEVICES AND MODALITIES
Incisionless magnetic compression anastomosis with the extensive use of magnets in endosurgical techniques, the new techniques of creating magnetic compression anastomosis with the help of endoscopically deployed octagonal magnets (IAS, GI Windows, Boston) have been developed and gastrojejunostomy and gastroileostomy are now feasible with these devices. In this technique, the two octagonal endoscopically placed smart magnets get self assembled and the magnetic compression between the two magnetic rings create a large opening by necrosis of the intervening tissue.32 It is believed that the early entry of nutrients in terminal ileum shall induce the ileal break phenomenon which will induce food intake and improve the glycemic status.33
Duodenal Mucosal Resurfacing
Duodenal mucosal resurfacing (Fractyl Laboratories, Cambridge, MA) utilizes a device called Revita that is used initially to lift the duodenal mucosa with saline followed by radiofrequency ablation (Fig. 10) of the mucosa below the level of ampulla of vater.
Apart from the radiofrequency ablation, recirculating hot water balloons have also been used,34 with the objective of destroying the diseased duodenal mucosa and it is hypothesized that the re-epithelized normal mucosa shall result in improving the glycemic status of the patient due to enteroendocrine changes in the re-epithelized cells.
Revisional Therapies after Weight Regain
Various newer endoscopic revisional therapies are proposed for weight regain after Roux-en-Y bypass and other bariatric procedures. Most of those are based on the anatomical factors of weight regain although the genetic, behavioral, and physiological factors need to be ruled out. The anatomical factors commonly attributed to such weight regain are dilated pouch, dilated stoma, fistula to gastric remnant, and short Roux loop.
The common procedures proposed and being performed for stoma narrowing with proven technical feasibility and safety are sclerotherapy (Fig. 11), Endoclinch, Apollo Over Stitch, and very recent one, the OTSC clips.35 In one of the largest study, 94 patients with dilated gastrojejunal stoma with mean stoma diameter of 35 mm, the stoma could be reduced to 8 mm after OTSC clips (80% reduction), and at the end of 1 year, the mean BMI dropped from 45.8 to 27.4 (Fig. 12).36
Endoscopic suturing for late dumping syndrome for dilated gastric pouch is feasible and safe and has been studied extensively and one of the recent study encompassing 14 patients who underwent this, in 13 of the 14 patients no dumping was observed after 1 month of endoluminal surgery.37
Endoscopic bariatric therapy is a comparatively new technique and technology in the hand of an endosurgeon. Although more than four devices and procedures have received FDA approval for use in the United States, there are various other newer versions of those devices that are undergoing randomized controlled trials to develop and mimic a procedure that mimics a bariatric surgical procedure and gives similar outcome. The ASGE and the American Society for Metabolic and Bariatric Surgery (ASMBS) has given guidelines for newer novel procedures before considering those procedures for clinical use.
The two main criteria of this threshold are that the device associated risk and complication should not exceed 5% and the EWL of 25% must be achievable at the end of 12 months.38 One more observation about the endoscopic procedures is that the results and weight loss achieved may be temporary and transient and thus most of these procedures cannot be recommended as a standalone procedure and must be considered along with a multimodal regimen.
- Farina MG, Baratta R, Nigro A, et al. Intragastric balloon in association with lifestyle and/or pharmacotherapy in the long-term management of obesity. Obes Surg. 2012;22:565–71.
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- Nieben OG, Harboe H. Intragastric balloon as an artificial bezoar for treatment of obesity. Lancet. 1982;1:198–9.
- Lindor KD, Hughes RW, lllustrup DM, et al. Intragastric balloons in comparison with standard therapy for obesity: a randomized double blind trial. Mayo Clin Pro. 1987;62:992–6.
- Galloro G, Palma GD, Cantanzano C, et al. Preliminary endoscopic technical report of a new silicon intragastric balloon in the treatment of morbid obesity. Obes Surg. 1999;9:68–71.
- Konopko-Zubrzycka M, Baniukiewicz A, Wróblewski E, et al. The effect of intragastric balloon on plasma ghrelin, leptin and adiponectin levels in patients with morbid obesity. J Clin Endocrinol Metab. 2009;94(5):1644–9.
- Gómez V, Woodman G, Abu Dayyeh BK. Delayed gastric emptying as a proposed mechanism of action during intragastric balloon therapy: results of a prospective study. Obesity. 2016;24:1849–53.
- Hogan RB, Johnson LH, Long BW. A double blind, randomized sham controlled trial of the gastric bubble for obesity. Gastrointest Endosc. 1989;35:381–5.
- Benjamin SB. Small bowel obstruction and the Garren Edwards balloon: an intragastric bezoar. Gastrointest Endosc. 1988;34:463–7.
- US Food and Drug Administration. (2015). Medical devices cleared or approved by FDA in 2015. US Department of Health and Human Services. [online] Available from http://www.fda.gov/MedicalDevices/ProductsandMedicalProcedures/DeviceApprovalsandClearances/Recently-ApprovedDevices/ucm430692.htm.
- Bernate P, Francini F, Zangrandi F. Green urine after intragastric balloon placement for the treatment of morbid obesity. Surg. 2003;13:95–3.
- Roman S, Napoleon B, Mion F. Intragastric balloon for nonmorbid obesity. A retrospective evaluation of tolerance and efficacy. Obes Surg. 2001;11:646–8.
- Eynden FV, Urbain P. Small intestinal gastric balloon impaction treated by laparoscopic surgery. Obes Surg. 2001;11:646–8.
- Alfredo G, Roberta M, Francesca F, et al. Intragastric balloon for obesity treatment: results of multicentric evaluation for balloons left in place for more than 6 months. Surg Endosc. 2015;29(8):2339–43.
- Kotzampassi K, Grosomanidis V, Papakostas P, et al. 500 intragastric balloons: what happens 5 years thereafter? Obes Surg. 2012;22(6):896–903.
- Ponce J, Woodman G, Swain J, et al. The REDUCE pivotal trial: a prospective, randomized controlled pivotal trial of a dual intragastric balloon for the treatment of obesity. Surg Obes Relat Dis. 2015;11:874–81.
- Brooks J, Srivastava ED, Mathus-Vliegen EM. One-year adjustable intragastric balloons: results in 73 consecutive patients in the UK. Obes Surg. 2014;24(5):813–9.
- Mion F, Ibrahim M, Marjoux S, et al. Swallowable Obalon® gastric balloons as an aid for weight loss: a pilot feasibility study. Obes Surg. 2013;23(5):730–3.
- Machytka E, Chuttani R, Bojkova M, et al. Elipse, a procedure less gastric balloon for weight loss: a proof-of-concept pilot study. Obes Surg. 2016;26(3):512–6.
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- Marinos G, Eliades C, Raman Muthusamy V, et al. Weight loss and improved quality of life with a nonsurgical endoscopic treatment for obesity: clinical results from a 3- and 6-months study. Surg Obes Relat Dis. 2014;10(5):929–34.
- Forssell H, Noren E. A novel endoscopic weight loss therapy using gastric aspiration: results after 6 months. Endoscopy. 2015;47(1):68–71.
- Sullivan S, Stein R, Jonnalagadda S, et al. Aspiration therapy leads to weight loss in obese subjects: a pilot study. Gastroenterology. 2013;145(6):1245–52.e1-5.
- Thompson CC, Abu Dayyeh BK, Kushner R, et al. Percutaneous gastrostomy device for the treatment of class II and class III obesity: results of a randomized controlled trial. Am J Gastroenterol. 2017;112:447–57.
- Lopez-Nava G, Sharaiha RZ, Galvao Neto M, et al. Endoscopic sleeve gastroplasty for obesity: a multicenter study of 242 patients with 18 months follow-up. Gastroenterology. 2016;150(4S1):S26.
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- Sullivan S, Swain JM, Woodman G, et al. Randomized sham-controlled trial evaluating efficacy and safety of endoscopic gastric plication for primary obesity: The ESSENTIAL trial. Obesity (Silver Spring). 2017;25:294–301.
- Abu Dayyeh BK, Edmundowicz SA, Jonnalagadda S, et al. Endoscopic bariatric therapies. Gastrointest Endosc. 2015;(5):1073-86.
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- Stier C, Chiappetta S. Endoluminal revision of the dilated gastroenterostomy in patient with late dumping syndrome after proximal Roux-en-Y gastric bypass. Obes Surgery. 2016;26(8):1978–84.
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