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Ghanem, Omar M.

https://orcid.org/0000-0002-5725-8497

Mayo Clinic

Agency for Science, Technology and Research

Citations 55

Computer Vision Applications in Laparoscopic Cholecystectomy: Are We Ready? A Systematic Review
Hossain, Intekhab, Alomar, Abdulrahman , Tham, Daniel, Salehinejad, Hojjat , Ghanem, Omar M., Madani, Amin, Laplante, Simon, Ghanem, Omar M. , Madani, Amin , Laplante, Simon

Surgical Innovation | August 14, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1177/15533506261477478 Get It

This systematic review evaluates current computer vision models and their applications in laparoscopic cholecystectomy. Using PRISMA guidelines, we analyzed studies reporting on primary computer vision model applications in laparoscopic cholecystectomy, from inception to March 2026. A total of 85 studies were included: workflow analysis (n = 26), anatomy recognition and segmentation (n = 14), safety assessment (n = 14), instrument detection (n = 12), tissue/image characterization (n = 7), event detection and scene understanding (n = 6), and surgical performance assessment (n = 6). The performance of the computer vision models in the studies was heterogeneous, with accuracy, F1-score, mean average precision, Dice coefficient, mean absolute error, and area under the receiver operating characteristic curve being commonly reported. Despite strong model performances in several studies, implementation in the clinical setting remains a challenge. We highlight the need for standardized model performance reporting, broader external and multi-institutional validation of models, and coordinated frameworks for safe and effective implementation of computer vision models in laparoscopic cholecystectomy.
Reverse EUS-GJ: EUS guided decompression of Excluded Stomach Gastric Outlet Obstruction (eGOO) after Roux-en-Y Gastric Bypass Surgery
Valls, E Vargas, Gala, K, Ghanem, O, Abimansour, J, Han, S, Law, E, Dayyeh, B Abu, Chandrasekhara, V, Vargas, Eric J. , Ghanem, Omar M. , AbiMansour, Jad P. , Han, Samuel, Dayyeh, Barham K. Abu , Chandrasekhara, Vinay

Endoscopy | June 5, 2026 | Volume: 58 | Issue: S 03 | Pages: S809-S810

10.1055/s-0046-1822242 Get It

Toward a Standardized Definition of Distal (Ileal) Metabolic Bariatric Surgery: An International Modified Delphi Consensus
Leon-Ballesteros, Guillermo Ponce de, Pouwels, Sjaak, Ghanem, Omar M., Arana, Sebastián, Rodriguez, Christian, Aceves, Manuel , Berry, Marcos, Brown, Wendy, Caiazzo, Robert, Carbajo, Miguel A., Cottam, Daniel, Dib, Victor, Dillemans, Bruno, Elli, Enrique F., Estrada, Roberto, Ferraro, Ariel, Gutiérrez-Rojas, Carlos A., Herrera, Miguel F., Huang, Chih‐Kun , Panagiotis, Lainas, MARTINEZ, SANDY, NAVARRETE, SALVADOR, Ortiz, Elias, Pantoja, Juan Pablo, Parmar, Chetan, Pattou, F , Ponce, Jaime , Ramirez, Christian, Ribeiro, Rui , Rodriguez-Esquerra, Antonio, Romero, Gustavo, Rotundo, Adriana, Salvi, Prashant, Sanchez-Pernaute, Andres, Santoro, Sérgio , Topart, Philippe, Torres, Antonio, Ungson, Gilberto , Weiner, Sylvia, Zerrweck, Carlos, León‐Ballesteros, Guillermo Ponce de , Pouwels, Sjaak , Ghanem, Omar M. , Arana-Garza, Sebastián, Angrisani, Luigi , Berry, Marcos A. , Brown, Wendy, Caiazzo, Robert J. , Carbajo, Miguel‐A., Chiappetta, Sonja , Cottam, Daniel Rhead , Dib, Victor Ramos Mussa , Dillemans, Bruno , Elli, Enrique F. , Ferraro, Ariel, Gutiérrez-Rojas, Carlos Alberto , Herrera, Miguel F. , Kermansaravi, Mohammad , Kurian, Marina S. , Laïnas, Panagiotis , Madalosso, Carlos Augusto Scussel , Martinez, Sandy, Parmar, Chetan D. , Salvi, Prashant H., Sánchez-Pernaute, Andrés , Topart, Philippe A. , Weiner, Sylvia R., Zerrweck, Carlos

No container title available | June 2, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-9765725/v1 Get It

Abstract Background Distal (ileal) metabolic bariatric surgeries (DMBS) have gained increasing adoption due to their enhanced metabolic effects. However, the absence of standardized definitions, classification, and clinical indications limits their consistent application. This consensus aimed to establish an international consensus on the definition, classification, indications, and postoperative management of DMBS. Methods A three-round modified Delphi study was conducted including international expert surgeons from 16 countries. A total of 98 statements were developed across three domains: procedural characteristics, patient selection, and postoperative follow-up. Consensus was defined as ≥75% agreement. Statements not reaching consensus were revised and resubmitted. Results Consensus was achieved on 81 statements. DMBS were defined as procedures involving gastro-ileal or duodeno-ileal bypass, emphasizing ileal stimulation as a key metabolic mechanism. Procedures with a common channel ≤350 cm, including single-anastomosis duodenal-ileal with SG (SADI-S), single anastomosis sleeve-ileal transit bipartition (SASI), sleeve gastrectomy with Roux-en-Y transit bipartition (SG+TB), and biliopancreatic diversion with duodenal switch (BPD-DS), as well as one-anastomosis gastric bypass (OAGB) with biliopancreatic limb > 50% of total small bowel length were classified as DMBS. Routine measurement of total small bowel length was strongly recommended. DMBS were considered appropriate as primary procedures in patients with BMI ≥40 kg/m² with comorbidities, a BMI ≥50–60 kg/m², irrespective of the presence of comorbidities, and as revisional options for suboptimal clinical response (SoCR), recurrent weight gain (RWG), or persistent metabolic disease. Comprehensive preoperative and multidisciplinary evaluation was deemed mandatory, and liver cirrhosis, heart failure, end-stage kidney disease, and inflammatory bowel disease were considered contraindications. Postoperative care requires lifelong multidisciplinary follow-up, with increased attention to nutritional deficiencies and supplementation. Conclusions This consensus provides a standardized framework for DMBS, supporting harmonization of practice and improved patient safety.
A Comprehensive Analysis of Predictors of Marginal Ulcers After Roux-en-Y Gastric Bypass: A Cohort Review of 2106 Patients
Abedalqader, Tala, Migliorini, Alberto, Cerecedo, Leonardo Garcia , Ghazal, Nour El , Klim, Joseph , Boutros, Tony, Laplante, Simon , Ghanem, Omar M., El Ghazal, Nour , Laplante, Simon J , Abedalqader, Tala , Ghanem, Omar M.

Medicina | April 29, 2026 | Volume: 62 | Issue: 5 | Pages: 838

10.3390/medicina62050838 Get It

Background and Objectives: Roux-en-Y gastric bypass (RYGB) is one of the most commonly performed metabolic and bariatric surgeries worldwide. Marginal ulcers (MU) are a common complication following RYGB, yet their pathophysiology and the contributing risk factors to their development are not fully understood. Materials and Methods: This retrospective cohort study examined patients who underwent RYGB between January 2008 and December 2023, with 1 to 5 years of follow-up. Data collected included patient- and procedure-related risk factors, as well as postoperative MU events. Statistical analysis methods included the independent samples t-tests, multivariate regression, and Cox regression analyses. Results: Our final cohort included 2106 patients and was predominantly female (80.5%), with a mean age of 47.8 ± 12.1 years and body mass index (BMI) of 45.5 ± 7.5 kg/m2. MU occurred in 241 (11.4%) patients, with a mean time to occurrence of 4.5 ± 0.02 years. History of smoking (HR = 1.87, p < 0.001) and gastroesophageal reflux disease (HR = 2.36, p < 0.001) significantly increased hazard for MU, while proton pump inhibitor use (HR = 0.18, p < 0.001) was associated with reduced hazard. Aspirin exposure, regardless of dose and chronicity, did not impact MU. Conclusions: Our findings highlight the importance of preoperative assessment and counseling in patients planning to undergo RYGB. Patient-related factors should guide postoperative monitoring and prophylaxis of MU, as this remains a debated topic amongst experts.
Metabolic and Bariatric Surgery vs Glucagon-like peptide-1 Receptor Agonist Therapy
Ghusn, Wissam, Abedalqader, Tala, Ghazal, Nour El, Espinosa, Maria Antonia, Villamarin, Jose, Gutierrez, Rene Rivera, Castaneda, Regina , Bechenati, Dima , Fansa, Sima , Hurtado, Maria D., Acosta, Andres, Ghanem, Omar M., Jawhar, Noura , El Ghazal, Nour , Castaneda, Regina , Ghusn, Wissam , Vierkant, Robert A. , Abedalqader, Tala , Villamarin, Jose L. , Gutiérrez, René de Jesús Rivera , Hurtado, M D, Acosta, Andres , Ghanem, Omar M.

Annals of Surgery | April 20, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1097/sla.0000000000007064 Get It

Objective: To compare 1-year changes in estimated 10-year and lifetime atherosclerotic cardiovascular disease (ASCVD) risk following metabolic and bariatric surgery (MBS) versus glucagon-like peptide-1 receptor agonist (GLP-1RA) therapy among adults with obesity. Summary Background Data: Obesity is a major driver of ASCVD through adverse metabolic and inflammatory pathways. Metabolic and bariatric surgery and GLP-1 receptor agonists represent the most effective contemporary treatments for obesity and are increasingly used to mitigate cardiovascular risk. However, their comparative effects on integrated short-term and lifetime ASCVD risk in real-world clinical practice remain incompletely characterized. Methods: We conducted a retrospective cohort study of adults with obesity (body mass index ≥30 kg/m²) who underwent MBS or initiated GLP-1RA therapy between 2020 and 2023 within a large tertiary health care system in the United States. Participants were identified from electronic health records and followed for 12 months. Primary outcomes were 1-year changes in estimated 10-year and lifetime ASCVD risk. Secondary outcomes included percent total body weight loss, blood pressure, and lipid parameters. Multivariable linear regression models were used to adjust for baseline body mass index and baseline ASCVD risk. Results: The final cohort included 812 patients, of whom 579 underwent MBS and 233 initiated GLP-1RA therapy. At baseline, patients receiving GLP-1RAs were older and had higher estimated ASCVD risk. At 1 year, reductions in 10-year ASCVD risk were similar between groups (−0.8% vs. −1.1%; P =.36). In contrast, lifetime ASCVD risk decreased significantly more following MBS than GLP-1RA therapy (−8.6% vs. −1.7%; P <.001). MBS was associated with greater percent total body weight loss (−27.8% vs. −11.1%; P <.001) and more favorable lipid changes, including larger reductions in low-density lipoprotein cholesterol and greater increases in high-density lipoprotein cholesterol. After adjustment, MBS remained independently associated with a greater reduction in lifetime ASCVD risk compared with GLP-1RA therapy (β −6.92; 95% CI −9.22 to −4.62). Conclusions: In this real-world cohort, both MBS and GLP-1RA therapy were associated with improvements in estimated cardiovascular risk, but MBS conferred substantially greater reductions in lifetime ASCVD risk, accompanied by superior weight loss and lipid improvements. These findings highlight the complementary roles of surgical and pharmacologic therapies in obesity management and may inform strategies to optimize long-term cardiovascular risk reduction.
Metabolic and bariatric surgery for patients with obesity type 1 diabetes mellitus: A comprehensive updated systematic review and meta‐analysis
Mitchell, Sebastian , Patwardhan, Ketaki, Geropoulos, Georgios, Lamb, PJ, Ghanem, Omar, Stimson, Roland H. , Lucocq, James E. , Geropoulos, Georgios, Ghanem, Omar M. , Robertson, Andrew G.

Diabetic Medicine | March 29, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1111/dme.70305 Get It

Abstract Aims This systematic review evaluated the impact of metabolic and bariatric surgery (MBS) on weight loss, glycaemic control, insulin requirements and postoperative complications. Methods A PRISMA‐compliant, PROSPERO‐registered systematic review and meta‐analysis (CRD42025123500) was conducted. Medline, PubMed, Embase, Scopus and CENTRAL were searched. Primary outcomes were changes in body weight, BMI, HbA1c and insulin requirements following MBS. Risk of bias was assessed using ROBINS‐I and RoB‐2, and certainty of evidence using GRADE. Results Twenty‐two studies, including 1324 adults with type 1 diabetes mellitus (mean age 42.2 ± 11.6 years; mean follow‐up 31.6 ± 18.2 months), were analysed. Of 753 participants with reported sex, 74.6% were women ( n = 562). A total of 1304 procedures were performed, most commonly Roux‐en‐Y gastric bypass (44.5%; n = 580) and sleeve gastrectomy (39.2%; n = 512), followed by adjustable gastric banding (13.0%; n = 170). Meta‐analysis demonstrated significant reductions in body weight (mean difference 29.55 kg; 95% CI 25.72 to 33.39; I 2 = 20%) and BMI (11.35 kg/m 2 ; 95% CI 10.36 to 12.34; I 2 = 32%). HbA1c decreased by 4 mmol/mol (95% CI 2.05 to 6.78; I 2 = 19%), and insulin requirements declined by 43%–48% (0.20 U/kg; 95% CI 0.13 to 0.26; I 2 = 58%). Postoperative complications included diabetic ketoacidosis (15/182, 8%) and severe hypoglycaemia (21/516, 4%); any complication occurred in 21/495 (4%). Evidence quality was low. Conclusion MBS achieves weight loss and reduces insulin requirements in adults with type 1 diabetes mellitus and obesity, but glycaemic improvements are minimal. Given the observational evidence base and inconsistent safety reporting, true metabolic risk remains uncertain. High‐quality prospective studies with standardised outcome definitions are needed.
The Complexities of Reoperative Metabolic and Bariatric Surgery–A Retrospective Review of Outcomes at a Single Large Institution
Bocchinfuso, Sara , Abedalqader, Tala, Ghazal, Nour El, Laplante, Simon , Mehta, Kabir , Ghanem, Omar M., Ghazal, Nour El , Jawhar, Noura , El Ghazal, Nour , Sample, Jack W. , Abedalqader, Tala , Ghanem, Omar M.

Surgical Laparoscopy, Endoscopy & Percutaneous Techniques | March 9, 2026 | Volume: 36 | Issue: 3 | Pages: No page available

10.1097/sle.0000000000001455 Get It

Background: Reoperative metabolic and bariatric surgery (MBS), consisting of revision and conversion surgery, carries higher morbidity and mortality compared with primary procedures, yet robust long-term data are limited. Methods: A retrospective review was conducted of all patients 18 years of age or older who underwent first-time reoperative MBS between 2000 and 2024 at a single large quaternary referral center. Data were stored securely and analyzed in R (v4.4.2) using standard descriptive statistics and group tests ( t tests/Wilcoxon/Kruskal-Wallis; χ²/Fisher). Sparse late-complication data precluded pairwise tests. Results: Three hundred sixty patients, 86% female, mean age 50 years, underwent reoperative MBS. Conversion to Roux-en-Y gastric bypass (49%) was the most common surgery. The majority were performed for weight recidivism (37%). Length of stay, estimated blood loss, length of surgery, complication rates, readmission rates, and reintervention rates varied by type of reoperative MBS performed and indication. Most early complications were Clavien-Dindo 2, and most late complications were Clavien-Dindo 3b for all approaches. There was one procedure-related death in the study following an open conversion. Conclusion: In this 24-year single-center cohort, weight recidivism was the most frequent indication for reoperation and was associated with improved perioperative outcomes and durable long-term weight loss. As the landscape of bariatric surgery continues to evolve, we recommend early referral to centers with reoperative MBS expertise.
Procedure-Specific Early Complications Following Bariatric Surgery: A High-Volume Single-Institution Analysis
Ghusn, Wissam , Ghazal, Nour El , Kellogg, Todd A., Ghanem, Omar M., El Ghazal, Nour , Mosleh, Kamal Abi , Jawhar, Noura , Salameh, Yara , Ghanem, Omar M.

Surgical Laparoscopy, Endoscopy & Percutaneous Techniques | September 22, 2025 | Volume: 35 | Issue: 6 | Pages: No page available

10.1097/sle.0000000000001406 Get It

Background: Metabolic and bariatric surgery (MBS) is an established treatment for severe obesity and its related comorbidities. While long-term outcomes are often emphasized, early postoperative complications remain a critical metric of safety and resource utilization. Large database studies have reported national trends in MBS outcomes but are limited by lack of granularity, inconsistent definitions, and inclusion of heterogeneous surgical experience. This study aimed to provide a detailed analysis of 30-day postoperative complications following sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and duodenal switch (DS) over a 17-year period at a single high-volume quaternary academic center. Materials and Methods: A retrospective cohort study of adult patients who underwent primary laparoscopic SG, RYGB, or DS between 2008 and 2024. All procedures were performed by fellowship-trained, minimally invasive bariatric surgeons. Complications occurring within 30 days postoperatively were identified through comprehensive chart review and classified using the Clavien-Dindo grading system. Primary outcomes included incidence, severity, and type of complications, as well as rates of readmission, reoperation, and reintervention. Multivariable logistic regression was used to identify predictors of overall and major complications. Results: Of 2190 patients included, 413 (18.9%) experienced at least 1 early complication, totaling 467 discrete events. DS had the highest complication rate (29.3%), followed by RYGB (18.4%) and SG (17.5%). RYGB was associated with a high burden of major complications, including anastomotic strictures, GI bleeding, and reoperations for obstruction or leak. The 30-day rates of readmission (2.0%) and reoperation (1.3%) were low across all groups. Independent predictors of major complications included venous stasis (aOR=3.22), renal insufficiency (aOR=2.65), and type 2 diabetes (aOR=1.96); both RYGB (aOR=2.25) and DS (aOR=2.77) carried higher risk than SG. Conclusion: This study provides a granular, procedure-specific profile of early complications after SG, RYGB, and DS. While all 3 procedures demonstrated acceptable safety profiles, DS had the highest overall complication rate, and RYGB carried the greatest burden of major complications. These findings underscore the variability in early postoperative outcomes by procedure type and reflect the value of institutional experience in characterizing complication profiles.
Global Variations in Practices After Bariatric and Metabolic Surgery; the PARTNER study
Clyde, Danielle , Grant, Callum, Canales, Juan Andres Aguiar, Adib, Reza, Baig, Sarfaraz Jalil , Bhasker, Aparna Govil , Beaux, Andrew de, Drummond, Gillian, Fawal, Hayssam, Goodpaster, Kasey , Hopkins, George, Jatana, Anita , Kothari, Shanu N. , Kow, Lillian, Faria, Sílvia Leite , Madhok, Brij, Mahon, David, Miller, Karl , Nimeri, Abdelrahman , O’Kane, Mary , Poggi, Luis , Ratcliffe, Denise , Sarkar, Rupa , Shenfine, Jon, Sogg, Stephanie , Suter, Michel , Taha, Safwan , Voon, Kelvin , Lamb, Peter , Mahawar, Kamal , Grant, Callum, Canales, Juan Andres Aguiar, Cameron, David, Copăescu, Cătălin , Clare, Ken , Fried, Martin , Graham, Yitka N. H. , Goel, Ramen , Hazebroek, Eric J. , Husain, Farah Anwari , Joyce, Brian, Kermansaravi, Mohammad , Miras, Alexander Dimitri , Moizé, Violeta , Neto, Manoel Galvão , Peterli, Ralph , Sakran, Nasser , Salminen, Paulina , Singhal, Rishi , Stenberg, Erik , Tahrani, Abd A. , Vilallonga, Ramón , Welbourn, Richard , Zerrweck, Carlos , Moussa, Osama , Byrne, James Patrick , Parmar, Chetan D. , Ghanem, Omar M. , Robertson, Andrew G. , Yang, Wah

No container title available | August 6, 2025 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.21203/rs.3.rs-6779565/v1 Get It

Abstract Background: With over 1 billion individuals affected globally, obesity and obesity related diseases is now a leading cause of death. Metabolic and bariatric surgery (MBS) has emerged as a cornerstone intervention for severe obesity and its associated comorbidities. Despite its efficacy, postoperative care and follow-up after MBS remains highly variable worldwide. Objective: The PARTNER study aimed to evaluate global clinical practices in the postoperative management following MBS by surveying multidisciplinary healthcare professionals . Methods: This study was an international online survey conducted between October 2024 and January 2025. A multidisciplinary team developed the questionnaire based on existing literature and international guidelines. The survey assessed five domains: follow-up care, postoperative treatment, dietary management, patient support, and measurement of surgical outcomes. Responses were analysed descriptively. Results: A total of 262 responses were received from 62 countries. Most respondents were bariatric surgeons (72.1%) working in public healthcare systems (73.3%). While 78.7% reported conducting three-month postoperative reviews, only 23.7% offered indefinite follow-up. Hybrid models of care (virtual and in-person) were common (56.9%). VTE prophylaxis and postoperative PPI use were recommended by 64.1% and 84.3% respectively. Nearly all respondents (98.1%) provided dietary advice, with protein and micronutrient supplementation widely endorsed. Only 56.1% routinely referred patients for psychological follow-up. Definitions of surgical success and failure varied widely, with inconsistent objective outcome measures. Conclusion: The PARTNER study reveals significant international variation in postoperative management practices following MBS. These findings underscore the need for more standardized, evidence-based guidelines to improve long-term outcomes and equity of care worldwide.