Challenges of Revisional Metabolic and Bariatric Surgery: A Comprehensive Guide to Unraveling the Complexities and Solutions of Revisional Bariatric Procedures.

Revisional metabolic and bariatric surgery (RMBS) presents unique challenges in addressing weight loss failure or complications arising from initial bariatric procedures. This review aims to explore the complexities and solutions associated with revisional bariatric procedures comprehensively, offering insights into the evolving terrain of metabolic and bariatric surgery. A literature review is conducted to identify pertinent studies and expert opinions regarding RMBS. Methodological approaches, patient selection criteria, surgical techniques, preoperative assessments, and postoperative management strategies are synthesized to provide a comprehensive overview of current practices and advancements in the field, including institutional protocols. This review synthesizes key findings regarding the challenges encountered in RMBS, including the underlying causes of primary procedure failure, anatomical complexities, technical considerations, and assessments of surgical outcomes. Additionally, patient outcomes, complication rates, and long-term success are presented, along with institutional approaches to patient assessment and procedure selection. This review provides valuable insights for clinicians grappling with the complexities of RMBS. A comprehensive understanding of patient selection, surgical techniques, preoperative management, and postoperative care is crucial for enhancing outcomes and ensuring patient satisfaction in the field of metabolic bariatric surgery.

Laparoscopic Conversion of Gastric Plication to One Anastomosis Gastric Bypass.

Laparoscopic gastric plication (LPG) is a restrictive procedure to reduce the size of the stomach by folding and suturing the stomach to decrease its capacity. LGP has a high revision rate, mostly to sleeve gastrectomy. To the best of our knowledge, this is the first such report on the bariatric population that has been never described before.The purpose of this video was to show the feasibility and safety, as well as the main technical aspects, of a laparoscopic conversion of gastric plication to One Anastomosis Gastric Bypass.

Prevalence, Indications, and Complications of Conversional Surgery After Vertical Banded Gastroplasty: A MBSAQIP Analysis.

PURPOSE: Vertical banded gastroplasty (VBG) was once the most popular bariatric procedure in the 1980's, with many patients subsequently requiring conversional surgery. However, knowledge regarding the prevalence and outcomes of these procedures remains limited. This study aims to determine the prevalence, indications, rate of 30-day serious complications, and mortality of conversional surgery after VBG. MATERIALS AND METHODS: A retrospective analysis of the MBSAQIP database from 2020 to 2022 was conducted. Individuals undergoing conversional or revisional surgery after VBG were included. The primary outcomes were 30-day serious complications and mortality. RESULTS: Of 716 VBG conversions, the common procedures included 660 (92.1%) Roux-en-Y gastric bypass (RYGB) and 56 (7.9%) sleeve gastrectomy (SG). The main indication for conversion was weight gain for RYGB (31.0%) and for SG (41.0%). RYGB had longer operative times than SG (223.7 vs 130.5 min, p < 0.001). Although not statistically significant, serious complications were higher after RYGB (14.7% vs 8.9%, p = 0.2). Leak rates were higher after SG (5.4 vs 3.5%) but this was not statistically significant (p = 0.4). Mortality was similar between RYGB and SG (1.2 vs 1.8%, p = 0.7). Multivariable regression showed higher body mass index, longer operative time, previous cardiac surgery and black race were independently associated with serious complications. Conversion to RYGB was not predictive of serious complications compared to SG (OR 0.96, 95%CI 0.34-2.67, p = 0.9). CONCLUSIONS: Conversional surgery after VBG is uncommon, and the rate of complications and mortality remains high. Patients should be thoroughly evaluated and informed about these risks before undergoing conversion from VBG.

Bariatric Surgical Outcomes in the Elderly: A Comparison Study Between Primary and Revisional Procedures in the United Arab Emirates.

PURPOSE: Data reported on comparing primary and revisional procedures in the elderly is still limited. The aim of this study was to compare the efficacy and safety between primary and revisional bariatric surgery in a cohort of older patients. MATERIALS AND METHODS: All patients ≥ 60 years old were divided into two cohorts, primary surgery cohort (PSC) and revisional surgery cohort (RSC). Baseline and perioperative outcomes were analyzed. RESULTS: Fifty-eight patients were included (34 PSC and 24 RSC) in the study. Forty-two (25 PSC and 17 RSC) 72.4% were female. The mean age was 64 (± 3.3 years) in the PSC and 65 (± 4.2 years) in the RSC, the median initial BMI was 46.7 and 47.4 kg/m2 (p < 0.848), respectively. The mean hospital stay was (3 PSC vs. 5 RSC, p < 0.022) days. Readmissions occurred in (1 PSC vs. 3 RSC, p = 0.158) patients within 30 days of discharge. Postoperative major complications included (1 PSC vs. 5 RSC, p < 0.0278) patients. Reoperations were reported in (0 PSC vs. 3 RSC, p < 0.034) patients. Patients who underwent surgery for weight management, the initial mean BMI was (46.7 PSC vs. 47.4 RSC kg/m2, p = 0.848). At 12-months post-procedure, the mean BMI was (34.3 PSC vs. 37.7 RSC kg/m2, p = 0.372) and (23.7 PSC vs. 19.1 RSC, p = 0.231) %TBWL. The mean overall follow-up was (12.4 PSC vs. 27.5 RSC, p < 0.004) months, and one unrelated death (cancer) was reported in the RSC. CONCLUSION: PSC and RSC are effective in the elderly, however postoperative complications occurred more often in the RSC group.

Gastric bypass revisional surgery: percentage total body weight loss differences among three different techniques.

INTRODUCTION: Suboptimal weight loss or weight regain may occur after Roux-en-Y gastric bypass (RYGB). For this reason, revisional surgery has gained increasing interest. We aimed to compare the percentage of total body weight loss (%TBWL) at one-year follow-up among three different techniques: Jejuno-jejunostomy distalization (JJD), Sleeve resection of the gastrojejunostomy and gastric pouch (SRGJP), and the combination of both (JJD + SRGJP). METHODS: This retrospective cohort study included all patients who underwent revisional surgery after RYGB (2020-2021). The cohort was stratified by the type of revisional technique performed. Postoperative bariatric outcomes and nutritional deficiencies were compared among groups. RESULTS: A total of 78 patients underwent revisional surgery after RYGB: JJD was performed in 8 (10.3%), SRGJP in 34 (43.6%), and JJD + SRGJP in 36 (46.1%) patients. The most common indication for surgery was weight regain, in 72 (92.3%) patients. The median lengths of the BP limbs before and after distalization, were 50 cm (IQR 40-75 cm) and 175 cm (IQR 150-200 cm), respectively. The median length of the new common limb (NCL) and total alimentary limb length (TALL) were 277 cm (IQR 250-313 cm) and 400 cm (IQR 375-475 cm), respectively. Median percentage of total body weight loss (%TBWL) at one year was 15% (IQR 15-19%) for JJD, 20% (IQR 13-26%) for SRGJP, and 21% (IQR 15- 28%) for JJD + SRGJP (p = 0.40). CONCLUSIONS: In this study, the combined procedure (JJD + SRGJP) exhibited higher %TBWL at one year, however no statistically significant difference was identified among the three techniques.

Revisional surgery for malnutrition after SADI-S: prevalence, indications, techniques and outcomes.

KEY POINTS: SADIS with short common limb (< 250 cm) is a malabsorptive operation. Reoperation is advised in patients requiring admission for severe malnutrition. Elongation of the common channel is the preferred revisional technique Introduction: Single-Anastomosis Duodeno-Ileal bypass with Sleeve gastrectomy (SADI-S) is a modification of the duodenal switch. Initial common channel's length was 200, and after malnutrition was detected in some patients, it was elongated to 250 or 300 cm. The present study analyzes presentation and treatment of malnutrition after SADI-S. MATERIALS: Three hundred and thirty-three consecutive patients undergoing SADI-S between May 2007 and February 2019 were included. The common limb length was 200 cm in 50 cases, 250 cm in 211, 300 in 71 and 350 in 1. Thirty-one patients were admitted for severe hypoalbuminemia and 17 patients were submitted to revisional surgery, and constitute the series of our study. Mean weight before reoperation was 57 kg and mean body mass index (BMI) was 21 kg/m2. Mean number of daily bowel movements was 5,6. RESULTS: Mean time to reoperation was 56 months. The limb was found shorter than expected in 6 cases. Revisional surgery was conversion into a Roux en Y duodenal switch in 3 cases, elongation of the common limb in 11 patients, duodeno-duodenostomy in 1 and duodeno-jejunostomy to the first jejunal loop in 2. Mean weight regain was 14 kg, and mean final BMI 26 kg/m2. Daily bowel movements were reduced to 1,3. Factors related to hypoalbuminemia were hypertension, poor-controlled diabetes, shorter common limb and liver-test alterations. CONCLUSION: SADI-S is expected to be less malabsorptive than previous biliopancreatic diversions. However, caution must be taken with certain patients to avoid postoperative malnutrition. Adequate follow up with long-term supplementation is required.

One-Anastomosis Gastric Bypass (OABG) vs. Single Anastomosis Duodeno-Ileal Bypass (SADI) as revisional procedure following Sleeve Gastrectomy: results of a multicenter study.

PURPOSE: Sleeve Gastrectomy (SG) is the most performed bariatric surgery, but a considerable number of patients may require revisional procedures for suboptimal clinical response/recurrence of weight (SCR/RoW). Conversion options include One-Anastomosis Gastric Bypass (OAGB) and Single Anastomosis Duodeno-Ileal Bypass (SADI). The study aims to compare SADI vs. OAGB as revisional procedures in terms of early and mid-term complications, operative time, postoperative hospital stay and clinical outcomes. METHODS: All patients who underwent OAGB or SADI as revisional procedures following SG for SCR/RoW at three high-volume bariatric centers between January 2014 and April 2021 were included. Propensity score matching (PSM) analysis was performed. Demographic, operative, and postoperative outcomes of the two groups were compared. RESULTS: One hundred and sixty-eight patients were identified. After PSM, the two groups included 42 OAGB and 42 SADI patients. Early (≤ 30 days) postoperative complications rate did not differ significantly between OAGB and SADI groups (3 bleedings vs. 0, p = 0.241). Mid-term (within 2 years) complications rate was significantly higher in the OAGB group (21.4% vs. 2.4%, p = 0.007), mainly anastomotic complications and reflux disease (12% of OAGBs). Seven OAGB patients required conversion to another procedure (Roux-en-Y Gastric Bypass-RYGB) vs. none among the SADI patients (p = 0.006). CONCLUSIONS: SADI and OAGB are both effective as revisional procedures for SCR/RoW after SG. OAGB is associated with a significantly higher rate of mid-term complications and a not negligible rate of conversion (RYGB). Larger studies are necessary to draw definitive conclusions.

Five-year outcomes of revisional bariatric surgery: gastric band to sleeve gastrectomy or to Roux-en-Y gastric bypass.

BACKGROUND: Revisional bariatric surgery after an index adjustable gastric band (AGB) may be indicated to remedy weight relapse or band-related complications. We examined outcomes five years following revision from AGB to laparoscopic sleeve gastrectomy (AGB-LSG) or to Roux-en-Y gastric bypass (AGB-RYGB). METHODS: We conducted a retrospective review to identify patients (men and women, age 18-80) who underwent one revisional bariatric procedure with AGB as the index procedure at two medical centers in our healthcare system between January 2012 and February 2017. We only included patients with a pre-revision BMI > 30 kg/m2 for whom 5-year follow-up data were available. We compared 5-year weight loss and remission of comorbidities in patients undergoing AGB-LSG and AGB-RYGB conversion. RESULTS: A total of 114 patients met inclusion criteria (65 AGB-LSG, 49 AGB-RYGB). At 5-year post-revision, percent total weight loss (3.4% vs 19.9%; p < 0.001), percent excess weight loss (7.0% vs 50.8%; p < 0.001) and decrease in BMI (1.5 vs 8.8; p < 0.001) was greater in AGB-RYGB vs. AGB-LSG. No significant difference in remission or development of new comorbidities was observed. CONCLUSION: Conversion of AGB to RYGB is associated with superior intermediate-term weight loss compared to conversion of AGB to LSG. Future multicenter studies with larger sample sizes are necessary to further describe the intermediate-term outcomes of revisional bariatric surgery.

Safety of limb lengthening after Roux-en-Y gastric bypass: an analysis of the MBSAQIP database.

BACKGROUND: Roux-en-Y gastric bypass (RYGB) effectively treats severe obesity, but some patients may require revisional surgery like limb lengthening (LL) for postoperative weight gain. OBJECTIVES: This study aims to compare 30-day serious complications and mortality rates between LL and primary RYGB, given limited safety data on LL. METHODS: Patients who underwent LL and RYGB were identified from the 2020 and 2021 MBSAQIP databases, the only years in which LL data were available. Baseline characteristics and 30-day rates of serious complications and mortality were analyzed. RESULTS: A total of 86,990 patients underwent RYGB and 455 underwent LL. Patients undergoing RYGB were younger (44.4 versus 49.8 yr, P < .001), had a higher body mass index (BMI) (45.5 versus 41.8 kg/m2, P < .001) and higher rates of comorbidities including diabetes (30.0 versus 13.6%, P < .001). RYGB and LL had similar operative duration (125.3 versus 123.2 min, P = .5). There were no statistical differences between cohorts for length of stay (LOS) (1.6 RYGB versus 1.6 LL d, P = .6). After LL, there were higher 30-day rates of reoperation (3.3 versus 1.9%, P = .03) and deep surgical site infections (1.3 versus .5%, P = .03) compared to RYGB. There were no differences in overall serious complications (5.1 LL versus 5.0% RYGB, P = 1.0) and mortality (.2 LL versus .1% RYGB, P = .5). Multivariable logistic regression adjustment found that previous venous thromboembolism was associated with serious complications after LL. CONCLUSIONS: When compared to primary RYGB, LL has a favorable safety profile with similar 30-day rates of serious complications and mortality.

Posterior fixation of gastric tube with fibrin sealant in laparoscopic sleeve gastrectomy: a promising method to prevent revision surgeries.

BACKGROUND: We aim to assess the effects of gastric posterior fixation with fibrin sealant in laparoscopic sleeve gastrectomy in aspects of 12th-month body mass index and gastric volume. METHODS: The patients who underwent laparoscopic sleeve gastrectomy between January 2019 and February 2021 were divided into two groups preoperatively. The first 75 patients were appointed to the posterior fixation group, and the second 75 were to the control group. Changes in gastric volume and body mass index were assessed in the postoperative 12th month. RESULTS: There were 110 patients in the final analysis. Fifty-four patients had posterior fixation, and 56 had only laparoscopic sleeve gastrectomy. The posterior fixation group was superior in terms of total weight loss rate (39.1% vs. 34.5%, p<0.001) and less gastric volume increase rate (39.8% vs. 164.7%, p<0.001) in the postoperative 12th month. CONCLUSION: Our study suggests that posterior fixation with fibrin sealant in laparoscopic sleeve gastrectomy is a promising method for preventing weight regain and creating a need for revision surgery.

One Anastomosis Gastric Bypass as Revisional Surgery Following Sleeve Gastrectomy: A Systematic Review and Meta-Analysis.

BACKGROUND: Although sleeve gastrectomy (SG) is the most performed metabolic and bariatric surgery (MBS) worldwide, some patients require conversional procedures due to weight recurrence or late complications. Recently, one-anastomosis gastric bypass (OAGB) gained popularity as a viable option to address those problems. The aim of this meta-analysis is to assess the safety and efficacy of conversional OAGB after primary SG in the management of patients with obesity. METHODS: Cochrane, Embase, PubMed, Scopus, and Web of Science were searched for articles from their inception to February 2023 by two independent reviewers using the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) system. The review was registered prospectively with PROSPERO (CRD42023403528). RESULTS: From 1,117 studies screened, twenty studies met the eligibility criteria, with a total of 1,057 patients with obesity undergoing conversional OAGB after primary SG. The mean age ranged from 28.2 to 49.5 years, and 744 patients (75.2%) were women. At one year after revisional OAGB, the pooled mean percent excess weight loss (%EWL) was 65.2% (95%CI: 56.9, 73.4, I2 = 97%). The pooled mean %EWL after conversional OAGB was 71.1% (95%CI: 62.2, 80.0, I2 = 90%) at two years and 71.6% (95%CI: 61.0, 82.2, I2 = 50%) at five years. Additionally, resolution rates of diabetes and hypertension were 65.4% (95%CI: 0.522, 0.785, I2 = 65%) and 58.9% (95%CI: 0.415, 0.762, I2 = 89%), respectively. CONCLUSIONS: Our meta-analysis demonstrated OAGB as an effective conversional procedure after primary SG in terms of weight loss and obesity-associated medical problems for selected patients. Despite the promising results, further randomized controlled studies with larger sample sizes and more extended follow-up periods are necessary to determine if the OAGB is the best conversional surgery after SG.

Morbidity Associated With Distal Tibial Autograft Harvest.

Distal tibial autograft harvesting has been studied in the past, but morbidity at the level of the donor site is unclear. The purpose of this retrospective review is to assess morbidity in distal tibial autograft harvesting associated with foot and ankle arthrodesis procedures. A retrospective analysis was performed utilizing patients treated in the last 13 years at a large, multicenter, academic, tertiary referral, research institution. Included patients were between the ages of 18 and 80 years old. One-hundred and seven patients (39 male; 68 female) underwent ipsilateral distal tibial bone graft (n = 110) harvesting to augment the index procedure. Patients were followed for an average of 11.2 months after surgery (Range: 1-73 months). The incidence rate of distal tibial stress fractures was 4.5%, with an overall postoperative complication rate of 8.2%. Overall, low complication rates associated with distal tibial autograft harvesting were found, supporting the use of the distal tibia as an appropriate site for autograft harvesting in foot and ankle surgery.

Revisional One-Step Bariatric Surgical Techniques After Unsuccessful Laparoscopic Gastric Band: A Retrospective Cohort Study with 2-Year Follow-up.

BACKGROUND: Laparoscopic adjustable gastric banding (LAGB) has high reported rates of revision due to poor weight loss (WL) and high complication rates. Yet, there is yet to be a consensus on the best revisional procedure after unsuccessful LAGB, and studies comparing different revisional procedures after LAGB are still needed. METHODS: This was a retrospective cohort study that compared the outcomes of one-step revisional Roux-en-Y gastric bypass (rRYGB), one-anastomosis gastric bypass (rOAGB), or laparoscopic sleeve gastrectomy (rLSG) after LAGB. WL, complications, resolution of associated medical conditions, and food tolerance were assessed with a post hoc pairwise comparison one-way analysis of variance (ANOVA) throughout a 2-year follow-up. RESULTS: The final analysis included 102 (rRYGB), 80 (rOAGB), and 70 (rLSG) patients. After 2 years, an equal percentage of excess weight loss was observed in rOAGB and rRYGB (both >90%; p=0.998), significantly higher than that in rLSG (83.6%; p<0.001). In our study, no leaks were observed. rRYGB had higher complication rates according to the Clavien-Dindo classification (10.8% vs. 3.75% and 5.7% in rOAGB and rLSG, respectively, p=0.754), and re-operations were not statistically significant. Food tolerance was comparable between rOAGB and rRYGB (p = 0.987), and both had significantly better food tolerance than rLSG (p<0.001). The study cohorts had comparable resolution rates for associated medical problems (p>0.60). CONCLUSION: rOAGB and rRYGB had better outcomes after LAGB than rLSG regarding WL, feasibility, food tolerance, and safety. rOAGB had significantly higher rates of nutritional deficiencies.

Management of Leak by Intraoperative Megastent Insertion During Revisional Bariatric Metabolic Surgery: a Case Report.

We describe gastric tube continuity restoration (gastrogastrostomy) in a patient who underwent revisional laparoscopic one-anastomosis gastric bypass (OAGB) due to weight recurrence after laparoscopic sleeve gastrectomy (SG). The patient sought restoration to SG due to poor quality of life. A postoperative 11-mm leak at the site of the gastrogastrostomy, attributed to adhesions and edema from a marginal ulcer, complicated the procedure. As a result, laparoscopic exploration was performed, followed by insertion of a megastent. We hereby present video documentation of this case report as well as megastent insertion technique for the treatment of such complications.

One anastomosis gastric bypass vs sleeve gastrectomy as a revisional bariatric surgery for weight loss failure after primary restrictive procedure.

INTRODUCTION: Weight loss failure after restrictive bariatric procedures initiated the debate about the choice of an adequate revisional intervention, a question still unanswered. While many surgeons went for a conversion to gastric bypass, others opted for re-trying a revisional restrictive procedure to avoid the side effects of gastric bypass. The objective of our study was to compare weight loss outcome between revisional laparoscopic sleeve gastrectomy (re-LSG) and revisional one anastomosis gastric bypass (re-OAGB) for insufficient weight loss or weight regain following primary restrictive bariatric surgery. MATERIALS AND METHODS: We included 20 obese patients, with a history of weight regain or insufficient weight loss after primary restrictive surgery, who underwent re-LSG (eight patients) or re-OAGB (12 patients) between January 2018 and January 2021. Patients were followed up 2 years after their revisional intervention. Statistics were performed using IBM® SPSS® software for Windows version 21. RESULTS: In the re-LSG group, the average body mass index (BMI) before primary restrictive procedure was 43.7 kg/m2 . The average period between the primary and revisional surgery was 12.6 years. Patients had a nadir BMI of 33.2 kg/m2 during that period and reached a mean BMI of 40.6 kg/m2 before re-LSG. Two years after re-LSG, the average BMI was 31.5 kg/m2 with a percent of excess weight loss (%EWL) of 54% and percent of excess BMI loss (%EBMIL) of 66.6%. In the re-OAGB group, the average BMI before primary restrictive procedure was 39 kg/m2 . The average period between the primary and revisional surgery was 10.7 years. Patients had a nadir BMI of 30.5 kg/m2 during that period and reached a mean BMI of 36.5 kg/m2 before re-OAGB. Two years after re-OAGB, the average BMI was 27 kg/m2 with a %EWL of 86.7% and %EBMIL of 92.6%. CONCLUSION: For patients with insufficient weight loss or weight regain following primary restrictive bariatric surgery, re-OAGB has a better effectiveness in weight reduction compared with re-LSG after a 2-year follow up.

Robotic versus laparoscopic revisional bariatric surgeries: a systematic review and meta-analysis.

Purpose: In recent years, the need for revisional bariatric surgery (RBS) procedures has experienced a noteworthy surge to confront complexities and weight recidivism. Despite being a subject of controversy for many, the utilization of the Da Vinci robotic platform (Intuitive Surgical, Inc.) may present benefits in RBS. This study aimed to evaluate the outcomes of robotic RBS in comparison to Laparoscopic RBS. Methods: A meticulous and thorough analysis was ensured through a comprehensive exploration of the literature, which included PubMed, Medline, Scopus, and Cochrane. This exploration was conducted in adherence to the directives outlined in the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The Newcastle-Ottawa scale was used for quality assessment. Results: A total of 11 studies were included in this meta-analysis, comprising 55,889 in the laparoscopic group and 5,809 in the robotic group. No significant differences were observed in the leak, bleeding, operative time, or length of stay across both groups. However, the robotic group showed higher rates of conversion to open surgery (odds ratio [OR], 0.65; 95% confidence interval [CI], 0.53-0.79; p < 0.0001; I2 = 0%), reoperation (OR, 0.70; 95% CI, 0.57-0.87; p = 0.0009; I2 = 6%), and readmission (higher rate of readmission in the robotic group; OR, 0.76; 95% CI, 0.62-0.92; p = 0.005; I2 = 30%). Conclusion: Robotic-assisted bariatric surgery has no significant advantage over conventional laparoscopic surgery. Further research is warranted to explore and evaluate surgeons' methodology and proficiency differences.

One-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after failed laparoscopic sleeve gastrectomy (LSG): systematic review and meta-analysis of comparative studies.

INTRODUCTION: The aim of this study was to compare weight loss and gastroesophageal reflux disease (GERD) remission after one-anastomosis gastric bypass (OAGB) versus Roux-en-Y gastric bypass (RYGB) as revisional procedures after laparoscopic sleeve gastrectomy (LSG). METHODS: In PubMed, Embase, and Cochrane Library, a search was performed using the terms "Roux-en-Y gastric bypass versus one anastomosis gastric bypass," "revisional surgery," and "sleeve gastrectomy." Only original articles in English language comparing OAGB and RYGB were included. No temporal interval was set. The primary outcome measure was weight loss (%TWL). The secondary endpoints were leak, bleeding, marginal ulcer, and GERD. PRISMA flowchart was used. Differences in continuous and dichotomous outcome variables were expressed as mean difference (MD) and risk difference (RD) with 95% CI, respectively. Heterogeneity was assessed by using I2 statistic. RESULTS: Six retrospective comparative articles were included in the present meta-analysis. Weight loss analysis showed a MD = 5.70 (95% CI 4.84-6.57) in favor of the OAGB procedure with a statistical significance (p = 0.00001) and no significant statistical heterogeneity (I2 = 0.00%). There was no significant RD for leak, bleeding, or marginal ulcer after the two revisional procedures. After conversion to OAGB, remission from GERD was 68.6% (81/118), and it was 80.6% (150/186) after conversion to RYGB with a RD = 0.10 (95% CI -0.04, 0.24), no statistical significance (p = 0.19), and high heterogeneity (I2 = 96%). De novo GERD was 6.3% (16/255) after conversional OAGB, and it was 0.5% (1/180) after conversion to RYGB with a RD = -0.23 (95% CI -0.57, 0.11), no statistical significance (p = 0.16), and high heterogeneity (I2 = 92%).