1. BARIATRIC SERIES
Emerging technology: endoluminal treatment of obesity
´
Gregory A. Cote, MD, MS, Steven A. Edmundowicz, MD, FASGE
St. Louis, Missouri, USA
Background: Bariatric surgery remains the most effective treatment for the management of obesity. Endolumi-
nal interventions offer the potential for an ambulatory weight loss procedure that may be safer and more
cost-effective compared with current laparoscopic approaches.
Objective: We review the currently available endoluminal techniques for obesity that have been presented or
discussed in public forums and meetings, focusing on those with published trials.
Design: Literature review.
Results: Human trials of endoluminal treatments of obesity are primarily limited to restrictive interventions,
including intragastric balloons, transoral gastroplasty, and endoluminal vertical gastroplasty. Currently, the duo-
denojejunal bypass sleeve is the only endoluminal device that has been studied in humans that promotes weight
loss through malabsorption. Early results of these technologies are promising, but long-term data are lacking.
Conclusions: Endoluminal treatments for obesity have promise, and recent technological advances have been
astounding. However, these interventions will need to be held to the same standards of current operative tech-
niques. Each device will need to be scrutinized within clinical trials to determine its safety, efficacy, and durability.
(Gastrointest Endosc 2009;70:991-9.)
In a continuation of this series on endoscopic topics causes are attributable to technical complications such as
related to obesity, we are pleased to review the current postoperative infections and strictures.
status of endoluminal treatment of obesity. Bariatric sur- Despite the low rate of complications related to
gery remains the most effective intervention for persons laparoscopic bariatrics, there is a growing interest in
with a body mass index (BMI) of 40 or greater or those endoluminal and transgastric devices for preoperative or
with a BMI of 35 or greater with underlying comorbidities stand-alone weight loss procedures.5,6 Endoluminal sur-
such as diabetes, sleep apnea, and hypertension.1-3 Lapa- gery, performed entirely through the GI tract by using
roscopic techniques such as Roux-en-Y gastric bypass flexible endoscopy, offers the potential for an ambulatory
and gastric banding are increasingly preferred, with esti- weight loss procedure that may be safer and more cost-
mated mortality rates of 1% to 2%.4 Cardiopulmonary effective compared with current laparoscopic approaches.
events and anastomotic leaks are the most commonly If such an approach is developed, endoluminal therapy
cited sources of morbidity and mortality. Other important may extend the current indications for intervention to
those with multiple comorbidities, older age, and those
with mild obesity (BMI 30-35).
The human data on endoluminal surgery as a primary
Abbreviations: BIB, BioEnterics Intragastric Balloon; BMI, body mass modality for weight loss are limited. Current approaches
index; DJBS, duodenojejunal bypass sleeve; EndoCinch, endoluminal
vertical gastroplasty; %EWL, percentage of excess weight loss; GEJ,
vary from the use of intragastric balloons to endoluminal
gastroesophageal junction; TOGA, transoral gastroplasty. suturing or stapling as a means to modify gastric volume.
These are comparable to the purely restrictive interven-
DISCLOSURE: The following author disclosed financial relationships tions such as the gastric banding or vertical banded gas-
relevant to this publication: S. A. Edmundowicz: Stock options from
Satiety; research support from Davol; consultant to and research
troplasty. More nascent technology involves electrical
support from Boston Scientific. The other author disclosed no stimulation to delay gastric emptying7-9 or deploying
financial relationship relevant to this publication. a duodenojejunal sleeve as an intestinal bypass/malab-
Copyright ª 2009 by the American Society for Gastrointestinal Endoscopy
sorptive intervention. Other interesting approaches are
0016-5107/$36.00 on the horizon. We review the currently available endo-
doi:10.1016/j.gie.2009.09.016 luminal techniques for obesity that have been presented
www.giejournal.org Volume 70, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY 991
2. Emerging technology: endoluminal treatment of obesity ´
Cote & Edmundowicz
or discussed in public forums and meetings, focusing on
those with published trials. Because this field is rapidly
evolving, many of the concepts and devices are early
in their development and have yet to be evaluated in hu-
man trials.
Human studies of devices for weight loss are difficult to
design and complete. When assessing response to weight
loss devices, there are numerous confounding variables in-
cluding a strong placebo effect, variable patient compli-
ance with dietary instructions and exercise programs,
and limitations on randomization other than by BMI and
failure of standard medical weight loss programs before
enrollment. The ideal device trial design would be a ran-
domized, controlled, double-blind evaluation of the de-
vice in an identical environment of dietary control,
exercise, and patient education. Few devices have been
evaluated in this manner.
Comparison of the efficacy of endoluminal therapies
for weight loss can also be difficult. Although a number
of endpoints can be used, most studies calculate the per-
centage of excess weight loss (%EWL) as a measure of ef-
ficacy. For an individual patient, excess weight is calculated
as the difference between the patient’s weight and the re-
ported weight of an average body mass individual with
a BMI of 25. Some studies calculate the loss of excess
BMI by comparing the patient’s weight with that of a pa-
tient with the same height at a BMI of 25. This interval dif-
ference of the excess weight and the percentage of that
weight lost after a device intervention is the %EWL or
the percentage of excess BMI weight loss.
Weight loss after an intervention is not static, and many Figure 1. Intragastric balloon. A, The BioEnterics Intragastric Balloon.
individuals plateau and regain weight in the months to The balloon is smooth and spherical. The arrows at the equator point
toward the valve. The shell consists of inert, nontoxic silicone elastomer,
years after the intervention. To have a meaningful effect impervious and resistant to gastric acid. The radiopaque self-sealing and
on a patient’s health, the weight loss needs to be lasting. repenetrable valve with its Z-shape configuration (visible inside balloon)
Ideally, an endoluminal therapy would lead to modifica- allows adjustment of the balloon volume from 400 to 800 mL. B, Plain
tions of a patient’s eating habits to promote weight loss abdominal radiograph showing balloon in body of stomach. A coin taped
followed by long-term maintenance. Endoluminal thera- on the lower sternum permits follow-up comparisons of balloon size to
detect premature deflation. Reprinted with permission from Mathus-Vlie-
pies that are easy to apply and of low risk could be re- gen EM, Tytgat GN. Intragastric balloon for treatment-resistant obesity:
peated at variable intervals to promote more long-lasting safety, tolerance, and efficacy of 1-year balloon treatment followed by
weight loss. a 1-year balloon-free follow-up. Reprinted with permission from the
American Society of Gastrointestinal Endoscopy. Mathus-Vliegen EMH,
Tytgat GNJ. Intragastric balloon for treatment-resistant obesity: safety, tol-
erance, and efficacy of 1-year balloon treatment followed by a 1-year bal-
INTRAGASTRIC BALLOON loon-free follow-up. Gastrointest Endosc 2005;61:19-27.
One of the earliest concepts for the endoluminal treat-
ment of obesity involved deploying intragastric balloons to The device can be deflated by using a variety of needles
restrict oral intake.10-15 Initial experiences failed to achieve and removed with a snare or basket. As many as two thirds
meaningful weight loss or were met with significant com- of patients may report nausea and vomiting that in some
plications. A number of intragastric balloons have been in cases can require early removal. Other commonly cited
use worldwide, and several have been withdrawn from the complications include early deflation and gastric ulcera-
market. With a spherical shape and larger capacity than tions and erosions.
earlier models, the BioEnterics Intragastric Balloon (BIB) In a retrospective analysis of 2515 patients with
(Allergan, Irvine, Calif) is the intragastric balloon that a mean BMI of 44.8 Æ 7.8 kg/m2 who underwent endo-
has been most extensively studied. The BIB is deployed scopic placement of the BIB, only 2 (0.08%) were unsuc-
in the stomach under direct vision and inflated with 500 cessful.16 At 6-month follow-up, the %EWL was 33.9 Æ
to 700 mL of saline/methylene blue solution (Fig. 1). 18.7. During this interval, improvement or resolution
992 GASTROINTESTINAL ENDOSCOPY Volume 70, No. 5 : 2009 www.giejournal.org
3. ´
Cote & Edmundowicz Emerging technology: endoluminal treatment of obesity
Figure 2. Endoluminal suturing using endoluminal vertical gastroplasty (EndoCinch).22 A, Aspirate tissue just below the Z-line. B, Needle with pre-
loaded suture advanced. C, Cinching/deployment device advanced. D, Final appearance of placation in cardia. Reprinted with permission from Roth-
stein RI, Filipi CJ. Endoscopic suturing for gastroesophageal reflux disease: clinical outcome with the Bard EndoCinch. Gastrointest Endosc Clin N Am
2003;13:89-101.
of diabetes and hypertension was observed in 86.9% and ric intervention in thousands of patients. There is
93.7%, respectively. The authors reported a complication currently no intragastric balloon approved for use in
rate of 2.8%, including 5 (0.19%) patients in whom a gas- the United States. Although there is a greater body of
tric perforation developed, 2 of whom consequently evidence supporting the short-term efficacy and safety
died. Similar results were duplicated in a series of 26 of intragastric balloons, more provocative and potentially
high-risk, superobese patients with a mean BMI of 65.3 durable mechanisms are becoming available.
Æ 9.8 and at least 3 medical comorbidities such as diabe-
tes, hypertension, and sleep apnea.17 These patients Gastric restriction
were specifically identified as at unacceptable risk to un- Endoluminal vertical gastroplasty (EndoCinch).
dergo bariatric surgery as a primary intervention, so Has been described using the Bard EndoCinch Suturing
a BIB was inserted in anticipation of undergoing a weight System (C.R. Bard, Murray Hill, NJ). The EndoCinch was
loss surgery during a second stage. At 6-month follow-up initially devised for the endoscopic treatment of GERD.
in most patients, the %EWL was 22.4 Æ 14.5 and im- Its acceptance as a therapy for GERD has gained little trac-
provement/resolution of diabetes and hypertension tion because of its lack of durability and often incomplete
was 81% and 83%, respectively. One patient died within control of reflux symptoms.20-22 The suturing device is
24 hours of BIB placement as a result of severe aspira- contained within a capsule that is attached to the end of
tion. The efficacy of the intragastric balloon was further a diagnostic gastroscope. The initial procedure was per-
supported in a randomized, sham-controlled, crossover formed by using an overtube and required the use of 2
study of 32 patients.18 gastroscopes: one to sew, using the attached capsule
Newer designs have been proposed, allowing place- with suture with a T tag at the terminal end that is brought
ment under direct visualization into the gastric fundus through the tissue and out of the mouth, and one to lock
by pulling the balloon alongside the gastroscope by using the sutures in place using a suture anchor. To use this de-
a polypectomy snare.19 However, the durability of intra- vice, tissue is suctioned into the capsule and a hollow nee-
gastric balloon therapy is limited because the device is dle, preloaded with a T tag suture, is advanced through
typically removed after 6 months, returning the patient the captured tissue. In its original description for the treat-
to his or her baseline anatomy. Still, these have been ment of GERD, a second T tag is deployed before cinching
used successfully as a precursor to more definitive bariat- the 2 sutures together to lock the stitch in place (Fig. 2).
www.giejournal.org Volume 70, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY 993
4. Emerging technology: endoluminal treatment of obesity ´
Cote & Edmundowicz
Figure 3. Endoscopic suturing for vertical gastroplasty. Reprinted with permission from the American Society of Gastrointestinal Endoscopy. Fogel R,
De Fogel J, Bonilla Y, et al. Clinical experience of transoral suturing for an endoluminal vertical gastroplasty: 1-year follow-up in 64 patients. Gastrointest
Endosc 2008;68:51-8.
This procedure was repeated at the gastroesophageal in this trial have been reported in abstract form. Thompson
junction (GEJ) to create a plication and theoretically et al reported similar short-term efficacy with a newer ver-
reduce the amount of refluxate. sion of the endoluminal vertical gastroplasty device in a 2-
Fogel et al23 first described the use of the EndoCinch for center U.S. trial of 16 patients.24 A randomized, multicenter
the treatment of obesity in 64 patients. Seven sutures are de- trial is being initiated by Davol in the United States at this
ployed in a continuous and cross-linked fashion from the time.
proximal fundus to the distal body (Fig. 3). Once the suture The durability of the GEJ plication has been called into
is fixed, distention of the stomach is significantly limited. question in earlier trials of the EndoCinch for the treat-
The authors reported a mean procedure time of 45 minutes ment of GERD.20,21,25 Similar problems may arise because
and a recovery time of 1 to 2 hours, with all patients dis- this device is used to restrict gastric distensibility. Sham-
charged on the day of procedure. Of 64 patients, 59 were fol- controlled trials are needed to further evaluate the utility
lowed for 12 months post-procedure. The %EWL improved of this device in obesity. Well-designed studies with long-
from 21.1% at 1 month to 58.1% at 12 months (Fig. 4). Only term follow-up will be needed to measure the durability
14 patients underwent repeat endoscopy between 3 and 12 of the observed weight loss. Particularly, the stability of
months of follow-up to assess the suture line; of these, 11 the gastric sutures remains unproven given the lack of
remained completely or partially intact and did not require long-term data. Finally, the ease of repeated interventions
additional intervention. There were minimal complications to facilitate additional weight loss in refractory or recur-
reported. Recent attempts to duplicate the results obtained rent cases needs to be studied.
994 GASTROINTESTINAL ENDOSCOPY Volume 70, No. 5 : 2009 www.giejournal.org
5. ´
Cote & Edmundowicz Emerging technology: endoluminal treatment of obesity
sisted at 6-month follow-up in only 5 of 21. Despite this,
the %EWL was 24.4 after 6 months and procedure-related
adverse events were limited to the first week of follow-up,
including nausea, vomiting, and pain. With a second-gen-
eration stapler,26 an intact staple line was noted in 9 of
11 patients at discharge and persisted in 7 of 11 after 6
months of follow-up. Comparable to the initial experience,
the mean %EWL of 19.2% at 1 month and 46.0% at 6
months was significant.
TOGA is the first endoscopic device that offers trans-
mural tissue apposition, which may promote a more
durable sleeve than other instruments such as the Endo-
Cinch.23,28 With average procedure times of approximately
2 hours, the technique seems feasible and is likely to be an
ambulatory procedure as operators become more com-
Figure 4. Percentage of excess weight (%EWL) loss, segmented into sub-
fortable with the intervention. As with other restrictive
populations by body mass index (BMI) age (n Z 64). Post-op, postopera-
tively. Reprinted with permission from the American Society of procedures, the most challenging question for this
Gastrointestinal Endoscopy. Fogel R, De Fogel J, Bonilla Y, et al. Clinical approach will be the durability and extent of weight
experience of transoral suturing for an endoluminal vertical gastroplasty: loss. A randomized, sham-controlled trial is ongoing in
1-year follow-up in 64 patients. Gastrointest Endosc 2008;68:51-8. the United States to further investigate this technique.
Duodenojejunal bypass sleeve
Transoral gastroplasty The first strictly endoluminal device used to bypass the
Transoral gastroplasty (TOGA) (TOGA System; Satiety, proximal small intestine is the duodenojejunal bypass
Inc, Palo Alto, Calif) uses the first endoscopic stapling de- sleeve (DJBS) (GI Dynamics, Inc, Watertown, Mass). The
vice to create a full-thickness plication in the proximal device is composed of a self-expanding implant that seats
stomach.26,27 Using a strictly endoluminal approach, in the duodenum and is attached to a 60-cm plastic sleeve
TOGA creates a gastric sleeve along the lesser curvature that extends into the proximal jejunum (Fig. 6). The de-
of the stomach (Fig. 5). First, the TOGA Sleeve Stapler is vice is preloaded onto a wire-guided catheter system
introduced over a guidewire into the proximal stomach. that is advanced into the small bowel under fluoroscopy.
A gastroscope is advanced through the device and As described by Rodriguez-Grunert et al,29 the sleeve is de-
retroflexed to directly visualize the stapler. The greater ployed by pushing the inner sheath of the catheter into
curvature is retracted by using an extendable wire to opti- the proximal jejunum. Once the sleeve is fully extended,
mally align the stapler for plication. Then, using vacuum a self-expanding anchor is released in the duodenal bulb
pods with suction, the stapler attaches to the anterior to hold the device in place.
and posterior walls of the stomach. The stapler is closed In the first reported human series, the DJBS was suc-
and fired, allowing a serosa-to-serosa apposition in parallel cessfully deployed in all 12 patients with a mean implanta-
with the lesser curvature of the stomach creating a gastric tion time of 26.6 minutes.29 With the exception of 2
sleeve in this location. The stapler is withdrawn and re- patients in whom refractory abdominal pain developed re-
loaded. A second firing of the stapler allows the sleeve quiring early extraction, the device remained in place for
to be extended to a total length of 8 cm from the GEJ. 12 weeks and was successfully removed in a mean time
The sleeve’s luminal diameter of approximately 20 mm is of 43.3 minutes. Two complications, an oropharyngeal
reduced to approximately 12 mm by pleating the gastric tear and an esophageal mucosal tear, were reported in 2
sleeve by using the TOGA restrictor, which clamps and subjects at the time of device withdrawal. These did not
staples gastric folds together after acquiring tissue via require surgical intervention and were considered minor.
suction. This process can be repeated as needed to create The mean %EWL after 12 weeks was 23.6.
additional plications and further narrowing the lumen of A second human series was recently reported from
the sleeve. Chile evaluating sleeve placement in 25 patients compared
The initial feasibility of this technique in 33 human with 14 controls. Eighty percent of the subjects were able
subjects was reported by Moreno et al26 and Devire et e to keep the sleeve in place for 12 weeks. Major adverse
al27 in 33 patients. All subjects underwent transoral gastro- events included 3 upper GI bleeds, 1 anchor migration,
plasty with no significant complications. The mean BMI and 1 stent obstruction. The %EWL at 12 weeks was 22%
was more than 40 in both studies, and 1 or more comor- for the device versus 5% for the controls.30
bidities was present in as many as 40% at the onset. Using Future studies are needed to clarify the safety and du-
the earliest generation of the Sleeve Stapler,27 only 8 of 21 rability of the DJBS. The authors attributed symptoms of
patients had a fully intact sleeve at discharge, and this per- abdominal pain and bloating to a modest amount of tissue
www.giejournal.org Volume 70, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY 995
6. Emerging technology: endoluminal treatment of obesity ´
Cote Edmundowicz
Figure 5. Transoral gastroplasty (TOGA) sleeve stapler. A, The gastroscope is positioned in retroflexion to visualize the stapler at the gastroesophageal
junction. The retraction wire (arrow) helps to align the greater curvature optimally. B, Endoscopic view demonstrates that the stapler has been opened
and is ready for tissue acquisition by using vacuum pods (arrow). C, With suctioning, the stomach is collapsed, and tissue from the opposing walls is
acquired in the vacuum pods. D, The stapler is closed and fired, creating a full-thickness placation, as shown in E (arrow). Reprinted with permission
from Satiety Inc.
inflammation noted at the duodenal anchor. Can this type CONCLUSION
of implant remain intact indefinitely or will this also serve
as a precursor to a more definitive surgical intervention? There is a growing demand for less-invasive approaches
Endoluminal devices used to induce malabsorption are to the treatment of obesity. Endoluminal approaches in-
in the earliest phases of development but may offer the cluding prostheses, suturing, and stapling (Table 1) have
greatest potential in terms of long-term weight loss and promise. However, endoluminal therapies will need to
control of obesity-related comorbidities. be held to the same standards of current operative
996 GASTROINTESTINAL ENDOSCOPY Volume 70, No. 5 : 2009 www.giejournal.org
7. ´
Cote Edmundowicz Emerging technology: endoluminal treatment of obesity
Figure 5 (Continued )
TABLE 1. Developing endoluminal technology
Technological approach Device (manufacturer) Potential advantages Potential disadvantages
Prosthesis BioEnterics Intragastric Extensive experience, Limited durability (6 mo);
Balloon (Allergan, Irvine, O2000 reported cases in the patient intolerance (nausea,
Calif) literature; safety of vomiting)
endoscopic placement and
removal
Duodenojejunal bypass First malabsorptive Limited human data (12
sleeve (GI Dynamics, Inc, approach using endoscopy patients); safety and
Watertown, Mass) long-term efficacy unclear;
patient intolerance (2 of 12
required early removal)
Suturing/stapling devices EndoCinch (C. R. Bard, FDA approved device (for Limited human data
Murray Hill, NJ) GERD); safety data available (64 patients); durability
of sutures unclear
Transoral gastroplasty Offers transmural stapling to Limited human data
(Satiety, Inc, Palo Alto, Calif) plicate opposing walls of (33 patients) Durability of
stomach; early safety data gastric pouch unclear
favorable
FDA, U.S. Food and Drug Administration.
techniques. Each device should be scrutinized in clinical strategy. There will be particular interest in reversible strat-
trials to determine its safety and efficacy in facilitating egies that do not commit the patient to permanent surgi-
weight loss. In addition to inducing meaningful and sus- cal modification of the GI tract. In addition, there may be
tained reductions in BMI, a viable intervention should sig- a role for a trial of an endoluminal intervention to identify
nificantly reduce the rate of obesity-related comorbidities. committed patients for more decisive but costly and po-
Finally, endoluminal treatments will need to have a lasting tentially morbid operative procedures. There is hope
impact on weight loss that can be maintained for several that an effective, easily deployed therapy will be found
years after the primary intervention. Retreatment to main- to help the millions of people worldwide who are afflicted
tain weight loss by using relatively benign and inexpensive with morbid obesity. It is our obligation to carefully and
endoluminal therapies may need to be tested as a viable critically evaluate these devices and allow those that are
www.giejournal.org Volume 70, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY 997
8. Emerging technology: endoluminal treatment of obesity ´
Cote Edmundowicz
Figure 6. A, A depiction of the GI Dynamics sleeve in place preventing ingested contents from contacting the mucosa of the duodenum and proximal
jejunum. B, The GI Dynamics DJBS (duodenojejunal bypass sleeve). It consists of a nitinol retaining device and a 60-cm plastic sleeve that prevents
contact of food with bile and pancreatic secretions and the mucosa of the duodenum and proximal jejunum. C, The sleeve system is passed over a guide-
wire and then, under direct visualization, the sleeve is deployed over a deeply placed guidewire. D, With the sleeve in place, the retaining device is then
fully deployed in the duodenal bulb to anchor the device. The endoscope is used to visualize placement of the retaining device. E, For retrieval of the
sleeve, a cap is placed at the tip of the upper endoscope. The nitinol retaining device is then grasped with a forceps and brought into the cap. The entire
apparatus is then removed through the mouth. (With permission of GI Dynamics.)
proven safe and effective in this disease to flourish. It is ev- REFERENCES
ident that the technological advances leading to these en-
1. Sturm R. Increases in clinically severe obesity in the United States,
doluminal devices have been astounding, and the concept
1986-2000. Arch Intern Med 2003;163:2146-8.
of endoluminal treatment of obesity is quickly becoming 2. Adams TD, Gress RE, Smith SC, et al. Long-term mortality after gastric
a realitydone that we do not want to delay. bypass surgery. N Engl J Med 2007;357:753-61.
998 GASTROINTESTINAL ENDOSCOPY Volume 70, No. 5 : 2009 www.giejournal.org
9. ´
Cote Edmundowicz Emerging technology: endoluminal treatment of obesity
3. Sjostrom L, Narbro K, Sjostrom CD, et al. Effects of bariatric surgery 20. Schwartz MP, Wellink H, Gooszen HG, et al. Endoscopic gastroplication
on mortality in Swedish obese subjects. N Engl J Med 2007;357: for the treatment of gastro-oesophageal reflux disease: a randomised,
741-52. sham-controlled trial. Gut 2007;56:20-8.
4. Morino M, Toppino M, Forestieri P, et al. Mortality after bariatric 21. Mahmood Z, McMahon BP, Arfin Q, et al. Endocinch therapy for
surgery: analysis of 13,871 morbidly obese patients from a national gastro-oesophageal reflux disease: a one year prospective follow up.
registry. Ann Surg 2007;246:1002-7, discussion 1007-9. Gut 2003;52:34-9.
5. Schauer P, Chand B, Brethauer S. New applications for endoscopy: the 22. Rothstein RI, Filipi CJ. Endoscopic suturing for gastroesophageal reflux
emerging field of endoluminal and transgastric bariatric surgery. Surg disease: clinical outcome with the Bard EndoCinch. Gastrointest
Endosc 2007;21:347-56. Endosc Clin N Am 2003;13:89-101.
6. Hazey JW, Dunkin BJ, Melvin WS. Changing attitudes toward endolu- 23. Fogel R, De Fogel J, Bonilla Y, et al. Clinical experience of transoral
menal therapy. Surg Endosc 2007;21:445-8. suturing for an endoluminal vertical gastroplasty: 1-year follow-up in
7. Sallam HS, Chen JD, Pasricha PJ. Feasibility of gastric electrical stimu- 64 patients. Gastrointest Endosc 2008;68:51-8.
lation by percutaneous endoscopic transgastric electrodes. Gastroint- 24. Thompson CC, Brethauer SA, Chand B, et al. M1259 Transoral Gastric
est Endosc 2008;68:754-9. Volume Reduction as an Intervention for Weight Management
8. Xu X, Pasricha PJ, Chen JD. Feasibility of gastric electrical stimulation (TRIM) Multicenter Feasibility Study: a report of early outcomes.
by use of endoscopically placed electrodes. Gastrointest Endosc Gastroenterology 2009;136:A-384.
2007;66:981-6. 25. Mahmood Z, Zaheer A, Ang YS, et al. Endocinch treatment for gastro-
9. Yao S, Ke M, Wang Z, et al. Retrograde gastric pacing reduces food oesophageal reflux (GORD): retention of plications are essential to
intake and delays gastric emptying in humans: a potential therapy control GORD. Gut 2007;56:1027, author reply 1027.
for obesity? Dig Dis Sci 2005;50:1569-75. 26. Moreno C, Closset J, Dugardeyn S, et al. Transoral gastroplasty is safe,
10. Ramhamadany EM, Fowler J, Baird IM. Effect of the gastric balloon ver- feasible, and induces significant weight loss in morbidly obese patients:
sus sham procedure on weight loss in obese subjects. Gut 1989;30: results of the second human pilot study. Endoscopy 2008;40:406-13.
1054-7. 27. Deviere J, Ojeda Valdes G, et al. Safety, feasibility and weight loss after
11. Hogan RB, Johnston JH, Long BW, et al. A double-blind, randomized, transoral gastroplasty: first human multicenter study. Surg Endosc
sham-controlled trial of the gastric bubble for obesity. Gastrointest 2008;22:589-98.
Endosc 1989;35:381-5. 28. Awan AN, Swain CP. Endoscopic vertical band gastroplasty with an
12. Meshkinpour H, Hsu D, Farivar S. Effect of gastric bubble as a weight endoscopic sewing machine. Gastrointest Endosc 2002;55:254-6.
reduction device: a controlled, crossover study. Gastroenterology 29. Rodriguez-Grunert L, Galvao Neto MP, Alamo M, et al. First human ex-
1988;95:589-92. perience with endoscopically delivered and retrieved duodenal-jejunal
13. Benjamin SB, Maher KA, Cattau EL Jr, et al. Double-blind controlled bypass sleeve. Surg Obes Relat Dis 2008;4:55-9.
trial of the Garren-Edwards gastric bubble: an adjunctive treatment 30. Tarnoff M, Rodriguez L, Escalona A, et al. Open label, prospective, ran-
for exogenous obesity. Gastroenterology 1988;95:581-8. domized controlled trial of an endoscopic duodenal-jejunal bypass
14. McFarland RJ, Grundy A, Gazet JC, et al. The intragastric balloon: sleeve versus low calorie diet for pre-operative weight loss in bariatric
a novel idea proved ineffective. Br J Surg 1987;74:137-9. surgery. Surg Endosc 2009;23:650-6.
15. Nieben OG, Harboe H. Intragastric balloon as an artificial bezoar for 31. Mathus-Vliegen EM, Tytgat GN. Intragastric balloon for treatment-re-
treatment of obesity. Lancet 1982;1:198-9. sistant obesity: safety, tolerance, and efficacy of 1-year balloon treat-
16. Genco A, Bruni T, Doldi SB, et al. BioEnterics Intragastric Balloon: ment followed by a 1-year balloon-free follow-up. Gastrointest
the Italian Experience with 2,515 patients. Obes Surg 2005;15: Endosc 2005;61:19-27.
1161-4.
17. Spyropoulos C, Katsakoulis E, Mead N, et al. Intragastric balloon for
high-risk super-obese patients: a prospective analysis of efficacy.
Surg Obes Relat Dis 2007;3:78-83. Received July 15, 2009. Accepted September 6, 2009.
18. Genco A, Cipriano M, Bacci V, et al. BioEnterics Intragastric Balloon
(BIB): a short-term, double-blind, randomised, controlled, crossover Current affiliations: Washington University School of Medicine (S.A.E.) St.
study on weight reduction in morbidly obese patients. Int J Obes Louis, Missouri, Indiana University School of Medicine (G.A.C.),
(Lond) 2006;30:129-33. Indianapolis, Indiana, USA.
19. Carvalho GL, Barros CB, Okazaki M, et al. An improved intragastric bal- Reprint requests: Steven A. Edmundowicz, MD, Washington University
loon procedure using a new balloon: preliminary analysis of safety and School of Medicine, 660 South Euclid Avenue, Campus Box 8124, St. Louis,
efficiency. Obes Surg 2008;19:237-42. MO 63110.
www.giejournal.org Volume 70, No. 5 : 2009 GASTROINTESTINAL ENDOSCOPY 999