Safety and efficacy of adjustable gastric band conversion to laparoscopic sleeve gastrectomy: a retrospective cohort study of a single center’s experience

Introduction

Background

The weight loss mechanism induced by adjustable gastric band (AGB) was believed to be caused by satiety induction. This mechanism is achieved by creating a small pouch, and through the distension caused by food boluses, neural messages are generated causing more satiety. Although this mechanism seems effective, the AGB does not seem to affect the hormonal levels like ghrelin and leptin, which might hinder the long-term weight loss (1). The popularity of AGB varied worldwide since its implementation as a bariatric surgery (BS). Reported unsatisfactory outcomes have been attributed to suboptimal surgical techniques, inadequate follow-up, and the limitations of small sample sizes that studies have depended on; these factors undermined the robustness of the conclusions drawn from the available data (2). Since its introduction in the 1980s, the rise and fall of AGB have been evident in the literature. Initially, the expectations were that AGB would be considered a stable option in obesity management, probably due to its reversibility and simplicity (3). Long-term studies demonstrated promising results where O’Brien et al. showed a decent percentage excess weight loss (%EWL) over 10 years ranging from 35% to 60% (4). Another report by Favretti et al. demonstrated an %EWL of 35% to almost 50% over 10 years (5). Despite that, AGB started to fall behind and was overtaken by other procedures, namely the laparoscopic sleeve gastrectomy (LSG) and roux en-Y gastric bypass (RYGB), which led to the increasing rate of AGB removal followed by another BS (6).

Rationale and knowledge gap

Although the conversion of restrictive BS has been evaluated before, the optimal option for conversion is still debated. Some authors attribute the controversy to a technical standpoint, with conversional LSG being the easiest and fastest. Another argument is the potential of staple line leak with LSG because of the scarred tissue and the high-pressure nature of the procedure, which is avoided when converting AGB to a bypass surgery (7,8). The experience with AGB conversion in Saudi Arabia is not well reported in the literature. Sadly, this observation can be generalized to most primary BS, as indicated by the significant discrepancy between the increasing number of conducted BS compared to the insufficient publications originating from Saudi Arabia (9).

Objective

This study aims to report the experience of AGB conversion at a single private center in Saudi Arabia to evaluate the indication of conversion, the safety of one stage conversion to other BS, and the percentage of total weight loss (%TWL) and percentage of excess body mass index loss (%EBMIL) after 1 year. Additionally, the rate of weight loss in the same conversion group was compared at two points: nadir weight/body mass index (BMI) after AGB and 1-year post-conversion to LSG. Finally, patients converted from AGB to LSG were matched with patients who had undergone primary LSG to compare the efficacy of weight loss between primary and conversional LSG after 1 year from conversion. We present this article in accordance with the STROCSS reporting checklist (available at https://asj.amegroups.com/article/view/10.21037/asj-24-38/rc) (10).

Methods

Patients

This is a retrospective study conducted at a single private clinic in Riyadh Saudi Arabia. Patients subjected to AGB removal with conversion to LSG were included. Demographics, comorbidities, smoking, pre-band, pre-conversion weight/BMI, nadir weight/BMI after AGB, duration of band, indications for conversion, and operative time were collected. Patients aged 18 years and older with BMI above 30 kg/m² who were operated on from 2017 till 2021 were included in the study. Patients who underwent AGB removal and then, after a period of time, underwent LSG (2-staged approach) were excluded from the study. There is no consensus on the definition of weight regain (WR), although Voorwinde et al. have summarized most of the definitions mentioned in the literature, we used >5 BMI gain from nadir for its simplicity (11). Although recent studies advocate for reporting weight loss in %TWL, insufficient weight loss (IWL) was determined by percentage of excess weight loss <50% as it is the most common definition found in the literature (12). Band intolerance (BI) was defined as subjective complaints of dysphagia, odynophagia, or choking. These symptoms must be combined with either radiological evidence of changes in the band’s angle relevant to spinal column on upper contrast study and/or relief of symptoms after band deflation. %TWL and %EBMIL following band insertion at nadir weight and 1-year post conversion were calculated using the following equation (13):

TWL=[(Initialweight)−(postopweight)](Initialweight)×100%[1]

EBMIL=[(InitialBMI)−(postopBMI)][(InitialBMI)−25]×100%[2]

To assess the difference in weight loss between primary and conversion LSG, patients who were converted from AGB to LSG were matched with patients subjected to primary LSG based on age, gender, preoperative BMI, comorbidities, and American Society of Anesthesiologists (ASA) score from our database. The indication for primary LSG was according to the American Society of Metabolic and Bariatric Surgery recommendations (14). To assess the safety, complications were categorized and reported according to the Clavien Dindo classification (CDC) for surgical complications (15). All procedures were conducted by the same investigator (A.A.). The study is registered with the number “researchregistry11072” at researchregistry.com.

Preoperative evaluation

Patients were interviewed in the clinic and asked about relevant information, including comorbidities, medications, allergies, expectations, goals, and enthusiasm for different BS. All patients with AGB underwent band deflation by sterile measures using a needle to completely aspirate the fluids in the reservoir. An upper contrast study is performed appropriately. A preoperative investigation including basic laboratory tests, chest X-ray, and electrocardiography are completed. A clear consent is taken, which states conversion to LSG unless extensive adhesions preclude LSG, and an intraoperative decision is made either to postpone the conversion or to convert directly to gastric bypass.

Surgical technique and post-operative management

All operations were performed by a fellow trained of the Royal College of Physicians and Surgeons of Canada. After anesthesia induction, the abdomen is accessed through a 5 mm Visiport^TM in the above and to the left of the umbilicus, followed by a 5 mm port at left upper quadrant, a 5 mm port right upper quadrant, Nathanson retractor at epigastric area, a 15-mm port above and to the right of umbilicus. After general inspection, we tend to evaluate the position of the band and the amount of adhesions. Using LigaSure^TM sealing device, all adhesions that are commonly found in the liver are released. From the exterior part of the band that is visible, the gastro-gastric groove is identified and opened circumferentially until the band is fully released from the stomach. Any remnant capsule or fibrotic tissue is removed while preserving the gastric wall and avoiding injury (Figure 1). After removing the band, the gastric wall is inspected carefully for any signs of perforation or erosion. The capsule is removed from the area on which we plan to apply the stapler. Careful dissection and separation of the capsule from the stomach wall is paramount if it can be completed without jeopardizing it. Any hiatal hernia discovered is repaired with complete esophageal mobilization until 2–3 cm of intra-abdominal esophagus is achieved. An anterior and posterior nonabsorbable suture repair is our preferred method of hiatal hernia repair, followed by ensuring a smooth transition of the bougie through the repair to exclude any tightness. Using an energy device, the greater omentum is released from the greater curvature 4–5 cm from the pylorus, till reaching the gastroesophageal junction. The sleeve is constructed by stapling along the greater curvature using a 36 Fr bougie. We tend to leave 1–2 cm from the angle of his. The staple line is reinforced with 3-0 monofilament sutures, followed by omentopexy. The procedure is completed by removing the reservoir and closing the skin.

Figure 1 Dissection of the capsule from the gastric wall.

In case the adhesions were too extensive and located at the planned LSG staple line, which increases the risk of leak, conversion to one anastomosis gastric bypass (OAGB) is the usual option. The reason is that when performing OAGB it required transecting the stomach horizontally below the band area at the incisura, thus making it a safer option. Distal to the ligament of Treitz, 150 to 180 cm of jejunum is brought up, and a side-to-side gastrojejunostomy is constructed at 3-cm mark. The common enterotomy is closed using monofilament sutures, followed by the application of anti-kink sutures.

One patient had band erosion on endoscopy and was free of any symptoms. Intra-operatively, the band was almost intraluminal and was successfully removed (Figure 2). After the band was removed, the stomach wall was unhealthy and showed signs of perforation, which was not amenable for repair (Figure 3). The diseased part was resected, and conversion to RYGB by a hand-sewn near esophagojejunostomy was constructed (Figure 4).

Figure 2 Eroded band.

Figure 3 Evidence of air bubbles indicating perforation in a non-healthy gastric wall.

Figure 4 Hand sewn near-esophagojejunostomy.

Patients are kept NPO until the next day, when a contrast study is conducted to check for leaks or interrupted flow. If the contrast study is negative, feeding should start with clear fluids. The team and the clinical dietician assess patients with written instructions regarding diet intake, medications, and contact numbers in case of an emergency. Patients are seen 2 weeks later, then every 3 months with laboratory tests.

Statistical analysis

The Statistical Package for Social Sciences (IBM, SPSS, version 25) was used for conducting the statistical analysis of our data. This case-control study employed a sample of 26 cases and 52 controls, providing adequate statistical power for detecting significant differences and associations. Post-hoc power analysis using “G*Power” Sample Size Calculator indicated that this sample size yielded “80%” power to detect an effect size of 0.3, at α=0.05. Descriptive statistics were applied (i.e., frequencies and percentages for categorical variables, in addition to mean and standard deviation for quantitative variables). The normality of quantitative variables was assessed using the Shapiro-Wilk test, with a high P value (>0.05) indicating that the null hypothesis can be retained, i.e., no evidence of non-normality (Table 1).

Accordingly, the independent sample “t-test” was applied to compare normally distributed quantitative variables between the two study groups (e.g., TWL and EWL), while the “Mann-Whitney U-test” was applied as the non-parametric alternative for non-normally distributed quantitative variables (e.g., age, pre-revision weight, pre-revision BMI, BMI after 1 year and operative time). P values less than 0.05 were considered statistically significant.

Ethical approval

The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). Since this is a retrospective study, ethical approval and informed consent acquisition were waived by the ethics committee/IRB of Dr Sulaiman Al Habib Hospital institution.

Results

After reviewing the database, from January 2017 until January 2021, 45 patients were subjected to AGB conversion by the same surgeon. Twelve patients were managed in a 2-stage approach, and three patients had incomplete data and were excluded from the study. A total of 30 patients, including 22 females (73.3%) and 8 males (26.6%) were included in the study. The mean age was 41.2±10.9 years. Mean preoperative weight and BMI before conversion were 107.3±23.2 kg and 39.8±5.7 kg/m², respectively. Five patients had diabetes mellites (16.6%), 6 patients had hypertension (20%), 10 had dyslipidemia (33.3%), and 9 were smokers (30%). Indications for AGB conversion were mainly due to WR and BI (30%), followed by IWL and BI/ IWL only (26.6%). The mean duration of AGB insertion till conversion was 9.5±4.1 years. Twenty-six patients were converted to LSG, and four patients were converted to other BS (3 OAGB, 1 RYGB). The decision for OAGB in 3 patients was because of extensive adhesions that deemed LSG conversion risky. Conversion to RYGB in one patient was due to band erosion, and LSG was not applicable. Patients who were converted to bypass surgery were not included in the analysis (Figure 5).

Figure 5 Flow chart of patients subjected to AGB conversion. AGB, adjustable gastric band; LSG, laparoscopic sleeve gastrectomy; RYGB, roux-en Y gastric bypass; OAGB, one anastomosis gastric bypass.

One patient (3.33%) developed a staple line leak and required readmission within 30 days, managed with endoscopic fully covered stent insertion, total parental nutrition, and IV antibiotics until complete healing, and discharged home (CDC grade IIIa). Two patients (6.66%) developed GERD symptoms controlled by proton pump inhibitors (CDC grade II). One patient (3.33%) developed significant GERD after 1 year and was converted to RYGB (CDC grade IIIb).

Fifty-two patients subjected to primary LSG were matched with the conversional LSG. There were no differences in the demographics between the two samples (Table 2). There were no differences between conversional and primary LSG with regard to mean pre-operative weight (104.9±23.7 vs. 101.9±28.9 kg, P=0.79) and pre-operative BMI (39.2±5.8 vs. 37.7±4.2 kg/m², P=0.75). Operative time was significantly higher in the conversional group (111.3 vs. 46.9 min, P=0.01). After 1 year, %TWL was significantly higher in the primary LSG compared to conversional LSG (30.9%±7.5% vs. 26.1%±9.6%, P=0.03). When assessing outcome by the %EBMIL metric, a borderline significant difference between primary and conversional LSG was observed (76.9%±29.7% vs. 90.8%±26.9%, P=0.051).

Discussion

The mechanism behind weight loss by purely restrictive procedures seems to be rudimentary and straightforward. Patients will tend to avoid specific types of food and change their eating habits to prevent unpleasant experiences like regurgitation after AGB (16). Hormonal profile changes caused by BS are considered a strong drive for weight loss and its sustainability. Ghrelin, an appetite-stimulating hormone, is markedly reduced following LSG than the elevated levels after AGB, which is unfavorable and probably predisposes to WR/IWL (17). Tsouristakis et al. assessed the hormonal profile following restrictive procedures. They compared it to the profile following RYGB. The postprandial gut hormone profile after RYGB, mainly GLP-1 and PYY, was significantly elevated, unlike the unchanged profile with AGB. Even though ghrelin level was elevated in both groups, the RYGB group had more sustainable weight loss (18).

Comparative studies concur with the superiority of RYGB and LSG compared to AGB. In a prospective randomized trial, Nguyen et al. demonstrated better weight loss, resolution of comorbidities, and a lower rate of long-term complications with RYGB compared with AGB (19). Another large retrospective review of the Michigan Bariatric Surgery Collaborative data showed more sustainable weight reduction, a higher rate of comorbidity resolution, and better patient satisfaction with RYGB and LSG than AGB (20). In the sixth global registry report by the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), the AGB had dropped to the fourth most common BS. Despite these remarks, some patients preferred AGB over other procedures. One of the reasons behind the attractiveness of AGB was its reversibility and less invasive nature compared to other BS (21). In our sample, most patients (30%) opted for AGB because it was the only BS available at the time of surgery before the introduction of RYGB or LSG, but also the ability to remove it at any time was appealing.

Patients with AGB developing IWL/WR comprise a significant number and will be considering a different management; hence, a subsequent conversional BS is likely to occur in the future. If a conversion is not conducted after AGB removal, some patients will gain weight even with positive lifestyle changes and a satisfactory amount of physical activity (22,23). Moon et al. found similar weight loss between conversional RYGB and conversional LSG, but the conversional RYGB patients had a higher rate of comorbidities preoperatively; hence, the improvement/resolution of those comorbidities was more impressive in the conversional RYGB group (24). Unfortunately, a higher rate of complications (17.5% for conversional RYGB) than 8.3% for conversional LSG was observed. A similar finding was reported by Yeung et al. where patients revised to RYGB or LSG because IWL had equivalent %EWL and resolution of comorbidity rates but higher 30-day morbidity rates (18.8% or 12.5%, conversional RYGB vs. conversional LSG, respectively) (25). Because conversional RYGB is more demanding from a technical standpoint, it translated to longer operative time and higher blood loss. Angrisani showed similar results between conversional RYGB and conversional LSG regarding %EWL, comorbidity resolution, and sustainable weight loss over five years in a more homogenous study sample. However, dumping syndrome and internal hernia occurred with patients subjected to conversional RYGB (26). A recent systematic review comparing RYGB and LSG as a conversion option for AGB showed equivalent outcomes in terms of weight loss, with %EBMIL more than 70% at 12–24 months of follow-up (27,28). This is similar to our results, which fall in the same range, indicating similar efficacy of conversion in a different population. There are different conclusions in the literature regarding the best conversion option, but the consensus is that conversion is highly recommended after AGB removal regardless of the BS chosen (7,29). When it can be offered safely, we believe that LSG is an excellent choice for conversion after AGB because it is less demanding from a technical standpoint and shows promising results. It also allows us to reserve other options for conversion, i.e., RYGB or OAGB, in case WR/IWL occurs after conversional LSG.

Anastomotic leak is notoriously known as the “Achilles heel” for LSG. The rate of staple line leak following primary LSG can reach up to 3% (30,31). Full mobilization of the fundus is required for proper LSG, which can be slightly harmful if an aggressive dissection is made near the gastroesophageal junction and the Angle of His (32). In addition to other technical factors, since the blood supply at Angle of His is lower compared with other gastric areas, ischemic mechanisms can explain why leaks occur near the gastroesophageal area (33,34). Tan et al. found a thicker gastric wall and inflammatory changes in addition to decreased vascularity in the area of AGB. With these changes in mind, it is justified to worry about a higher leak rate during AGB removal and a concomitant LSG (35). Hence, we tend to dissect the capsule and the accompanying reactive tissue until reaching the stomach wall to allow perfect stapling. It is our practice to imbricate the staple line with reinforcement suture and gastropexy. Despite that, one of our patients (3.33%) developed a staple line leak, partially due to non-compliance to the postoperative instructions. Luckily, the patient was managed conservatively with stent placement, intravenous antibiotics, and parental nutrition until the leak was resolved.

The difference in efficacy between primary and conversional bariatric procedures could be attributed to technical factors or psychological causes (36,37). In the case of conversion from AGB to LSG, some reports investigated the efficacy of primary vs. conversional LSG. In the short term, weight loss after primary LSG was found to be significantly higher compared to conversional LSG (38). Contradictory results were also reported, with a comparable rate of weight loss between the primary and conversional LSG (39). In a relatively large number of patients, Noel et al. found that patients with primary LSG had faster weight loss in the first 2 years compared to those with conversional LSG. This significant observation became trivial after 5 years of follow-up, with both groups showing similar failure rates (40). Similarly, Alqahtani et al. found that LSG as the conversion choice poses a potential long-term satisfactory outcome (41). On the other hand, after 6 years of follow-up, Carandina et al. concluded that LSG as a conversion choice following AGB might not be optimal for all patients, and a more thorough evaluation is recommended (42). We found that conversion LSG had less %TWL after 1 year compared to primary LSG (26.1%±10% vs. 30.9%±7.5%, P=0.03), but when weight loss is reported by %EBMIL, the significance is almost nullified (78.7%±30.1% vs. 90.8%±26.9%, P=0.051). The more accurate way of reporting weight loss is debated in the literature, but more data suggest utilizing %TWL as it is more robust and less affected by BMI.

Only one aspect is controlled if we assume that LSG is performed according to the standardized technique. Patient compliance and dietary habits play a crucial aspect. Suppose weight loss after a conversion from a restrictive procedure to another restrictive type is dampened; in that case, calorie-dense foods that are easy to eat (sweets and soft drinks) are a significant culprit (43). Even if LSG’s efficacy and appropriateness after AGB have been questioned, the simplicity of the procedure is an attractive feature. Moreover, it allows for an additional option instead of switching to more technically demanding malabsorptive procedures.

Although our study reports an experience that is not commonly reported in the literature, i.e., private centers in Saudi Arabia, our study has limitations starting with the small sample size. Unfortunately, there is no BS database in Saudi Arabia where similar procedures can be pooled and data can be used to answer questions on a larger scale. Additionally, some of the data were retrospectively gathered from patients, so recall bias might undesirably impact the analysis. Since this study was conducted at a private hospital, adherence to follow-up appointments varied between patients due to financial reasons and unavailability of health insurance to all patients. Other results like nutritional outcome and comorbidities resolution were missing for a number of patients and could not draw a conclusion in that aspect.

Conclusions

Conversion of AGB to LSG is safe and doable at private centers in Saudi Arabia if it is conducted by a well-trained team. AGB is effective in weight loss but not sustainable for the long term, and hardware intolerance is highly inevitable, requiring removal and conversion to other BS. In the short term, weight loss after conversion BS is inferior compared to primary BS, longer follow-up is needed to confirm this observation.

Acknowledgments

The authors acknowledge Dr. Omar Alsarraj for his contribution in data collection and acknowledge Dr. Osama Mostafa for his contribution in statistical analysis.

Footnote

Reporting Checklist: The authors have completed the STROCSS reporting checklist. Available at https://asj.amegroups.com/article/view/10.21037/asj-24-38/rc

Data Sharing Statement: Available at https://asj.amegroups.com/article/view/10.21037/asj-24-38/dss

Peer Review File: Available at https://asj.amegroups.com/article/view/10.21037/asj-24-38/prf

Funding: None.

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://asj.amegroups.com/article/view/10.21037/asj-24-38/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). Since this is a retrospective study, ethical approval and informed consent acquisition for the current study was waived by ethics committee/IRB of Dr Sulaiman Al Habib Hospital institution.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

References

1. Dixon AF, Dixon JB, O’Brien PE. Laparoscopic adjustable gastric banding induces prolonged satiety: a randomized blind crossover study. J Clin Endocrinol Metab 2005;90:813-9. [PubMed]
2. Favretti F, Ashton D, Busetto L, et al. The gastric band: first-choice procedure for obesity surgery. World J Surg 2009;33:2039-48. [Crossref] [PubMed]
3. Buchwald H. Introduction and current status of bariatric procedures. Surg Obes Relat Dis 2008;4:S1-6. [PubMed]
4. O’Brien PE, MacDonald L, Anderson M, et al. Long-term outcomes after bariatric surgery: fifteen-year follow-up of adjustable gastric banding and a systematic review of the bariatric surgical literature. Ann Surg 2013;257:87-94. [Crossref] [PubMed]
5. Favretti F, Segato G, Ashton D, et al. Laparoscopic adjustable gastric banding in 1,791 consecutive obese patients: 12-year results. Obes Surg 2007;17:168-75. [PubMed]
6. Welbourn R, Hollyman M, Kinsman R, et al. Bariatric Surgery Worldwide: Baseline Demographic Description and One-Year Outcomes from the Fourth IFSO Global Registry Report 2018. Obes Surg 2019;29:782-95. [Crossref] [PubMed]
7. Chansaenroj P, Aung L, Lee WJ, et al. Revision Procedures After Failed Adjustable Gastric Banding: Comparison of Efficacy and Safety. Obes Surg 2017;27:2861-7. [PubMed]
8. Ardestani A, Lautz DB, Tavakkolizadeh A. Band revision versus Roux-en-Y gastric bypass conversion as salvage operation after laparoscopic adjustable gastric banding. Surg Obes Relat Dis 2011;7:33-7. [PubMed]
9. Paolino L, Pravettoni R, Epaud S, et al. Comparison of Surgical Activity and Scientific Publications in Bariatric Surgery: an Epidemiological and Bibliometric Analysis. Obes Surg 2020;30:3822-30. [Crossref] [PubMed]
10. Rashid R, Sohrabi C, Kerwan A, et al. The STROCSS 2024 guideline: strengthening the reporting of cohort, cross-sectional, and case-control studies in surgery. Int J Surg 2024;110:3151-65. [Crossref] [PubMed]
11. Voorwinde V, Steenhuis IHM, Janssen IMC, et al. Definitions of Long-Term Weight Regain and Their Associations with Clinical Outcomes. Obes Surg 2020;30:527-36. [Crossref] [PubMed]
12. El Ansari W, Elhag W. Weight Regain and Insufficient Weight Loss After Bariatric Surgery: Definitions, Prevalence, Mechanisms, Predictors, Prevention and Management Strategies, and Knowledge Gaps-a Scoping Review. Obes Surg 2021;31:1755-66. [Crossref] [PubMed]
13. Brethauer SA, Kim J, El Chaar M, et al. Standardized outcomes reporting in metabolic and bariatric surgery. Obes Surg 2015;25:587-606. [Crossref] [PubMed]
14. Eisenberg D, Shikora SA, Aarts E, et al. 2022 American Society for Metabolic and Bariatric Surgery (ASMBS) and International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO): Indications for Metabolic and Bariatric Surgery. Surg Obes Relat Dis 2022;18:1345-56. [Crossref] [PubMed]
15. Dindo D, Demartines N, Clavien PA. Classification of surgical complications: a new proposal with evaluation in a cohort of 6336 patients and results of a survey. Ann Surg 2004;240:205-13. [Crossref] [PubMed]
16. Burton PR, Brown WA. The mechanism of weight loss with laparoscopic adjustable gastric banding: induction of satiety not restriction. Int J Obes (Lond) 2011;35:S26-30. [Crossref] [PubMed]
17. Langer FB, Reza Hoda MA, Bohdjalian A, et al. Sleeve gastrectomy and gastric banding: effects on plasma ghrelin levels. Obes Surg 2005;15:1024-9. [Crossref] [PubMed]
18. Tsouristakis AI, Febres G, McMahon DJ, et al. Long-Term Modulation of Appetitive Hormones and Sweet Cravings After Adjustable Gastric Banding and Roux-en-Y Gastric Bypass. Obes Surg 2019;29:3698-705. [Crossref] [PubMed]
19. Nguyen NT, Kim E, Vu S, et al. Ten-year Outcomes of a Prospective Randomized Trial of Laparoscopic Gastric Bypass Versus Laparoscopic Gastric Banding. Ann Surg 2018;268:106-13. [Crossref] [PubMed]
20. Carlin AM, Zeni TM, English WJ, et al. The comparative effectiveness of sleeve gastrectomy, gastric bypass, and adjustable gastric banding procedures for the treatment of morbid obesity. Ann Surg 2013;257:791-7. [Crossref] [PubMed]
21. Opozda M, Wittert G, Chur-Hansen A. Patients’ reasons for and against undergoing Roux-en-Y gastric bypass, adjustable gastric banding, and vertical sleeve gastrectomy. Surg Obes Relat Dis 2017;13:1887-96. [Crossref] [PubMed]
22. Kirshtein B, Kirshtein A, Perry Z, et al. Laparoscopic adjustable gastric band removal and outcome of subsequent revisional bariatric procedures: A retrospective review of 214 consecutive patients. Int J Surg 2016;27:133-7. [Crossref] [PubMed]
23. Aarts EO, Dogan K, Koehestanie P, et al. What happens after gastric band removal without additional bariatric surgery? Surg Obes Relat Dis 2014;10:1092-6. [Crossref] [PubMed]
24. Moon RC, Teixeira AF, Jawad MA. Conversion of failed laparoscopic adjustable gastric banding: sleeve gastrectomy or Roux-en-Y gastric bypass? Surg Obes Relat Dis 2013;9:901-7. [Crossref] [PubMed]
25. Yeung L, Durkan B, Barrett A, et al. Single-stage revision from gastric band to gastric bypass or sleeve gastrectomy: 6- and 12-month outcomes. Surg Endosc 2016;30:2244-50. [Crossref] [PubMed]
26. Angrisani L, Vitiello A, Santonicola A, et al. Roux-en-Y Gastric Bypass Versus Sleeve Gastrectomy as Revisional Procedures after Adjustable Gastric Band: 5-Year Outcomes. Obes Surg 2017;27:1430-7. [Crossref] [PubMed]
27. Coblijn UK, Verveld CJ, van Wagensveld BA, et al. Laparoscopic Roux-en-Y gastric bypass or laparoscopic sleeve gastrectomy as revisional procedure after adjustable gastric band--a systematic review. Obes Surg 2013;23:1899-914. [Crossref] [PubMed]
28. Elnahas A, Graybiel K, Farrokhyar F, et al. Revisional surgery after failed laparoscopic adjustable gastric banding: a systematic review. Surg Endosc 2013;27:740-5. [Crossref] [PubMed]
29. Marin-Perez P, Betancourt A, Lamota M, et al. Outcomes after laparoscopic conversion of failed adjustable gastric banding to sleeve gastrectomy or Roux-en-Y gastric bypass. Br J Surg 2014;101:254-60. [PubMed]
30. Sakran N, Goitein D, Raziel A, et al. Gastric leaks after sleeve gastrectomy: a multicenter experience with 2,834 patients. Surg Endosc 2013;27:240-5. [Crossref] [PubMed]
31. Aurora AR, Khaitan L, Saber AA. Sleeve gastrectomy and the risk of leak: a systematic analysis of 4,888 patients. Surg Endosc 2012;26:1509-15. [Crossref] [PubMed]
32. Rosenthal RJInternational Sleeve Gastrectomy Expert Panel. International Sleeve Gastrectomy Expert Panel Consensus Statement: best practice guidelines based on experience of >12,000 cases. Surg Obes Relat Dis 2012;8:8-19. [Crossref] [PubMed]
33. Iossa A, Abdelgawad M, Watkins BM, et al. Leaks after laparoscopic sleeve gastrectomy: overview of pathogenesis and risk factors. Langenbecks Arch Surg 2016;401:757-66. [Crossref] [PubMed]
34. Saber AA, Azar N, Dekal M, et al. Computed tomographic scan mapping of gastric wall perfusion and clinical implications. Am J Surg 2015;209:999-1006. [Crossref] [PubMed]
35. Tan MH, Yee GY, Jorgensen JO, et al. A histologic evaluation of the laparoscopic adjustable gastric band capsule by tissue sampling during sleeve gastrectomy performed at different time points after band removal. Surg Obes Relat Dis 2014;10:620-5. [PubMed]
36. Abdulrazzaq S, Elhag W, El Ansari W, et al. Is Revisional Gastric Bypass as Effective as Primary Gastric Bypass for Weight Loss and Improvement of Comorbidities? Obes Surg 2020;30:1219-29. [Crossref] [PubMed]
37. Slegtenhorst BR, van der Harst E, Demirkiran A, et al. Effect of primary versus revisional Roux-en-Y gastric bypass: inferior weight loss of revisional surgery after gastric banding. Surg Obes Relat Dis 2013;9:253-8. [PubMed]
38. Barrett AM, Vu KT, Sandhu KK, et al. Primary sleeve gastrectomy compared to sleeve gastrectomy as revisional surgery: weight loss and complications at intermediate follow-up. J Gastrointest Surg 2014;18:1737-43. [Crossref] [PubMed]
39. Alqahtani AR, Elahmedi M, Alamri H, et al. Laparoscopic removal of poor outcome gastric banding with concomitant sleeve gastrectomy. Obes Surg 2013;23:782-7. [Crossref] [PubMed]
40. Noel P, Schneck AS, Nedelcu M, et al. Laparoscopic sleeve gastrectomy as a revisional procedure for failed gastric banding: lessons from 300 consecutive cases. Surg Obes Relat Dis 2014;10:1116-22. [Crossref] [PubMed]
41. Alqahtani AR, Elahmedi MO, Al Qahtani AR, et al. 5-year outcomes of 1-stage gastric band removal and sleeve gastrectomy. Surg Obes Relat Dis 2016;12:1769-76. [Crossref] [PubMed]
42. Carandina S, Genser L, Bossi M, et al. Laparoscopic sleeve gastrectomy after failed gastric banding: is it really effective? Six years of follow-up. Surg Obes Relat Dis 2017;13:1165-73. [Crossref] [PubMed]
43. Burgmer R, Grigutsch K, Zipfel S, et al. The influence of eating behavior and eating pathology on weight loss after gastric restriction operations. Obes Surg 2005;15:684-91. [Crossref] [PubMed]