Quantification of interstitial cells of Cajal and fibrosis during gastric per-oral endoscopic myotomy and its association with clinical outcomes.

Background and study aims Alterations to interstitial cells of Cajal (ICC) and collagen fibrosis have been implicated in the pathogenesis of gastroparesis. We aimed to evaluate the feasibility and safety of pyloric muscle sampling during gastric peroral endoscopic myotomy (G-POEM) and the association between pyloric ICC density and degree of fibrosis with clinical outcomes. Patients and methods This was a single-center prospective study of gastroparetic patients who underwent G-POEM and intraprocedural pyloric muscle biopsies between January 2022 and April 2023. ICC count was estimated using CD117 stain and trichome for collagen fibrosis. Clinical response to G-POEM was defined as an improvement of ≥ 1 point on the Gastroparesis Cardinal Symptom Index. Results Fifty-six patients (median age 60 years, 71.4% women) underwent G-POEM (100% technical success; 71.4% clinical response). ICC depletion (< 10/high-power field) and fibrosis were encountered in 70.4% and 75% of the cases, respectively. There was no difference in mean ICC count between G-POEM responders vs. non-responders (7±3.6 vs. 7.7±3.3; P = 0.9). There was no association between ICC density or degree of fibrosis with the etiology of gastroparesis, duration of symptoms, gastric emptying rate, or pyloric impedance planimetry. Patients who did not respond to G-POEM had a significantly higher degree of moderate/severe fibrosis when compared with those who responded (81.3% vs. 25%; P = 0.0002). Conclusions Pyloric muscle biopsies during G-POEM was feasible and safe. ICC depletion and pyloric muscle fibrosis are common in gastroparetic patients. The degree of fibrosis may be related to pyloric dysfunction and clinical response to G-POEM. Additional studies are needed to confirm these results.

Early childhood-onset rumination syndrome is clinically distinct from adolescent-onset rumination syndrome.

OBJECTIVES: Rumination syndrome (RS) beginning in early childhood or infancy is understudied and challenging to treat. Our objective is to compare the characteristics and outcomes of early-onset (EO) and adolescent-onset (AO) patients with RS. METHODS: We conducted an ambidirectional cohort study of children diagnosed with RS at our institution. Patients were included in two groups: EO (RS symptom onset ≤5 years and diagnosis ≤12 years) and AO (onset >12 years). Patient characteristics, severity, and outcomes were compared between the groups. RESULTS: We included 49 EO and 52 AO RS patients. The median ages of symptom onset and diagnosis in EO were 3.5 and 6 years, respectively; AO, 14.5 and 15 years. EO RS had a slight male predominance while AO was predominantly female (p = 0.016). EO patients were more likely to have developmental delay (24% vs. 8%, p = 0.029) and less likely to have depression (0% vs. 23%, p < 0.001) or anxiety (14% vs. 40%, p = 0.004). At baseline, EO RS was less severe than AO RS: EO RS had greater regurgitation frequency (p < 0.001) but lower vomiting frequency (p = 0.001), resulting in less meal skipping (p < 0.001), reliance on tube feeding or parenteral nutrition (p < 0.001), and weight loss (p = 0.035). EO RS symptoms improved over time: at follow-up, patients had lower regurgitation (p < 0.001) and vomiting frequency (p < 0.001) compared to baseline. CONCLUSION: EO RS is clinically distinct from AO RS, with differences in sex distribution, comorbid conditions, and severity of initial presentation. The pathogenesis and natural history of EO RS may be distinct from that of AO RS.

The Use of a Self-Assembling Peptide Gel for Stricture Prevention in the Esophagus after Endoscopic Submucosal Dissection: A U.S. Multicenter Prospective Study.

BACKGROUND AND AIMS: Post-operative stricture is serious common adverse event following extensive endoscopic submucosal dissection (ESD) in the esophagus. The self-assembling peptide (SA) gel has been shown to promote tissue healing and re-epithelialization. We aimed to evaluate the effect of the SAP gel for esophageal stricture prevention after ESD. METHODS: Multicenter prospective study of patients who underwent esophageal ESD followed by SAP gel application between March 2022 to December 2023. Patients were included if ESD mucosal defect involved ≥ 50% of the circumference of the esophagus. High-risk cases were defined as mucosal defects ≥75% of the circumference. Stricture was defined as the inability to pass an endoscope ≥8.9 mm in diameter or a narrow-caliber lumen in a patient with symptoms. RESULTS: A total of 43 patients (median age 71 years; 81.4% men) underwent ESD (median resected specimen size 50 mm) during the study period. SAP gel (median 3 mL) was successfully applied in all cases (median time 4 minutes). In aggregate, stricture occurred in 20.9% (9/43) of the cases. Stricture developed in 30.8% of the high-risk cases: 80% (4/5) after circumferential ESD and 19% (4/21) in those with defects ≥75% but <100% of the circumference. All cases of stricture resolved with endoscopic treatment. Three cases (6.9%) of postoperative bleeding occurred and were adequately managed endoscopically. CONCLUSION: We demonstrate that SAP gel application was easy, quick, and associated with a relatively low stricture rate comparable to other prophylactic methods. Additional comparative studies are needed to corroborate these preliminary findings.

Fixation of Proximal flange of Lumen Apposing Metal Stent using Through-the-Scope Endoscopic Suturing System to Prevent Stent Migration in Single-Session EUS-directed Transgastric ERCP: A Pilot Study.

BACKGROUND AND AIMS: With the global obesity pandemic, clinical scenarios requiring urgent ERCP in patients with gastric bypass surgery are on the rise and Single-Session Endoscopic Ultrasound-Directed Transgastric Endoscopic Retrograde Cholangiopancreatography (SS-EDGE) can effectively address these technical challenges. The aim of this study was to evaluate and describe safe and effective use of through-the-scope endoscopic suturing system for anchoring the lumen apposing metal stents (LAMS) during SS-EDGE. METHODS: Six patients with Roux-en-Y gastric bypass (RYGB) underwent SS-EDGE at our center. Through-the-scope endoscopic suturing system was used for anchoring the lumen apposing metal stents (LAMS) during SS-EDGE. RESULTS: Clinical and technical success was achieved in all six patients without any adverse events related to the procedure. No stent migration, pneumoperitoneum or gastrointestinal perforation noted. Upon 4 weeks follow-up, no stent migration was noted with Through-the-scope suturing system remained anchored. LAMS along with tacks were removed and gastric fistulae were successfully closed endoscopically in all patients to prevent weight gain. CONCLUSION: Use of through-the-scope endoscopic suturing can be a safe, reliable, and potentially cost-effective novel technique for LAMS fixation to successfully perform SS-EDGE in RYGB patients.

Evaluating Clinical Safety and Analytical Impact of Subvisible Silicone Oil Particles in Biopharmaceutical Products.

Silicone oil is a commonly used lubricant in pre-filled syringes (PFSs) and can migrate over time into solution in the form of silicone oil particles (SiOPs). The presence of these SiOPs can result in elevated subvisible particle counts in PFS drug products compared to other drug presentations such as vials or cartridges. Their presence in products presents analytical challenges as they complicate quantitation and characterization of other types of subvisible particles in solution. Previous studies have suggested that they can potentially act as adjuvant resulting in potential safety risks for patients. In this paper we present several analytical case studies describing the impact of the presence of SiOPs in biotherapeutics on the analysis of the drug as well as clinical case studies examining the effect of SiOPs on patient safety. The analytical case studies demonstrate that orthogonal techniques, especially flow imaging, can help differentiate SiOPs from other types of particulate matter. The clinical case studies showed no difference in the observed patient safety profile across multiple drugs, patient populations, and routes of administration, indicating that the presence of SiOPs does not impact patient safety.

Peroral endoscopic myotomy for spastic esophageal dysmotility among opioid users: a multicenter propensity score matching study.

BACKGROUND AND AIMS: Opioid-induced esophageal dysfunction (OIED) often presents as spastic esophageal disorders (SEDs) and esophagogastric junction outflow obstruction (EGJOO). The aim of this study was to evaluate and compare clinical outcomes of peroral endoscopic myotomy (POEM) for SEDs and EGJOO among opioid users and nonusers. METHODS: This propensity score (PS) matching study included consecutive opioid users and nonusers who underwent POEM for SEDs and EGJOO between January 2018 and September 2022. The following covariates were used for the PS calculation: age, sex, duration of symptoms, Eckardt score, type of motility disorder, and length of myotomy during POEM. Clinical response was defined as a post-POEM Eckardt score ≤3. RESULTS: A total of 277 consecutive patients underwent POEM during the study period. PS matching resulted in the selection of 64 pairs of patients strictly matched 1:1 (n = 128) with no statistically significant differences in demographic, baseline, or procedural characteristics or in the parameters considered for the PS between the 2 groups. Clinical response to POEM was significantly lower among opioid users (51 of 64 [79.7%]) versus nonusers (60 of 64 [93.8%]) (P = .03) at a median follow-up of 18 months. Among opioid users, higher opioid dose (>60 morphine milligram equivalents per day) was associated with a higher likelihood of failure to respond to POEM (odds ratio, 4.59; 95% confidence interval, 1.31-3.98; P = .02). CONCLUSIONS: Clinical response to POEM for SEDs and EGJOO is significantly lower among opioid users versus nonusers. There was a dose-relationship between opioids and response to POEM, with higher daily opioid usage associated with a higher likelihood of treatment failure.

Development and initial validation of a video-based peroral endoscopic myotomy assessment tool.

BACKGROUND AND AIMS: Video analysis has emerged as a potential strategy for performance assessment and improvement. We aimed to develop a video-based skill assessment tool for peroral endoscopic myotomy (POEM). METHODS: POEM was deconstructed into basic procedural components through video analysis by an expert panel. A modified Delphi approach and 2 validation exercises were conducted to refine the POEM assessment tool (POEMAT). Twelve assessors used the final POEMAT version to grade 10 videos. Fully crossed generalizability (G) studies investigated the contributions of assessors, endoscopists' performance, and technical elements to reliability. G coefficients below .5 were considered unreliable, between .5 and .7 as modestly reliable, and above .7 as indicative of satisfactory reliability. RESULTS: After task deconstruction, discussions, and the modified Delphi process, the final POEMAT comprised 9 technical elements. G analysis showed low variance for endoscopist performance (.8%-24.9%) and high interrater variability (range, 63.2%-90.1%). The G score was moderately reliable (≥.60) for "submucosal tunneling" and "myotomy" and satisfactorily reliable (≥.70) for "active hemostasis" and "mucosal closure." CONCLUSIONS: We developed and established initial content and response process validity evidence for the POEMAT. Future steps include appraisal of the tool using a wider range of POEM videos to establish and improve the discriminative validity of this tool.

Intramodule pressure profiles and protein accumulation during tangential flow filtration.

Tangential flow filtration (TFF) through a 30 kDa nominal molecular weight cut-off (MWCO) ultrafiltration membrane is widely employed to concentrate purified monoclonal antibodies (mAbs) to levels required for their formulation into injectable biologics. While TFF has been used to remove casein from milk for cheese production for over 35 years, and in pharmaceutical manufacture of biotherapeutic proteins for 20 years, the rapid decline in filtration rate (i.e., flux) at high protein concentrations is a limitation that still needs to be addressed. This is particularly important for mAbs, many of which are 140-160 kDa immunoglobulin G (IgG) type proteins recovered at concentrations of 200 mg/mL or higher. This work reports the direct measurement of local transmembrane pressure drops and off-line confocal imaging of protein accumulation in stagnant regions on the surface of a 30 kDa regenerated cellulose membrane in a flat-sheet configuration widely used in manufacture of biotherapeutic proteins. These first-of-a-kind measurements using 150 kDa bovine IgG show that while axial pressure decreases by 58 psi across a process membrane cassette, the decrease in transmembrane pressure drop is constant at about 1.2 psi/cm along the 20.7 cm length of the membrane. Confocal laser scanning microscopy of the membrane surface at the completion of runs where retentate protein concentration exceeds 200 mg/mL, shows a 50 µm thick protein layer is uniformly deposited. The localized measurements made possible by the modified membrane system confirm the role of protein deposition on limiting ultrafiltration rate and indicate possible targets for improving membrane performance.

Low delayed bleeding and high complete closure rate of mucosal defects with the novel through-the-scope dual-action tissue clip after endoscopic resection of large nonpedunculated colorectal lesions (with video).

BACKGROUND AND AIMS: Complete closure after endoscopic resection of large nonpedunculated colorectal lesions (LNPCLs) can reduce delayed bleeding but is challenging with conventional through-the-scope (TTS) clips alone. The novel dual-action tissue (DAT) clip has clip arms that open and close independently of each other, facilitating tissue approximation. We aimed to evaluate the rate of complete closure and delayed bleeding with the DAT clip after endoscopic resection of LNPCLs. METHODS: This was a multicenter prospective cohort study of all patients who underwent defect closure with the DAT clip after EMR or endoscopic submucosal dissection (ESD) of LNPCLs ≥20 mm from July 2022 to May 2023. Delayed bleeding was defined as a bleeding event requiring hospitalization, blood transfusion, or any intervention within 30 days after the procedure. Complete closure was defined as apposition of mucosal defect margins without visible submucosal areas <3 mm along the closure line. RESULTS: One hundred seven patients (median age, 64 years; 42.5% women) underwent EMR (n = 63) or ESD (n = 44) of LNPCLs (median size, 40 mm; 74.8% right-sided colon) followed by defect closure. Complete closure was achieved in 96.3% (n = 103) with a mean of 1.4 ± .6 DAT clips and 2.9 ± 1.8 TTS clips. Delayed bleeding occurred in 1 patient (.9%) without requiring additional interventions. CONCLUSIONS: The use of the DAT clip in conjunction with TTS clips achieved high complete defect closure after endoscopic resection of large LNPCLs and was associated with a .9% delayed bleeding rate. Future comparative trials and formal cost-analyses are needed to validate these findings. (Clinical trial registration number: NCT05852457.).

AGA Clinical Practice Update on Endoscopic Full-Thickness Resection for the Management of Gastrointestinal Subepithelial Lesions: Commentary.

DESCRIPTION: Subepithelial lesions of the gastrointestinal tract are not encountered uncommonly during routine endoscopy. There has been remarkable progress in the development of endoscopic options for the resection of subepithelial lesions, including full-thickness resection. The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update (CPU) is to describe the various techniques for endoscopic full-thickness resection and to facilitate their appropriate application in the management of subepithelial lesions. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology.

ENDOSCOPIC SUBMUCOSAL DISSECTION WITH VERSUS WITHOUT TRACTION FOR PATHOLOGICALLY STAGED T1B ESOPHAGEAL CANCER: A MULTICENTER RETROSPECTIVE STUDY.

BACKGROUND & AIMS: Positive vertical margins (VM) are common after endoscopic submucosal dissection (ESD) of T1b esophageal cancer (EC) and are associated with an increased risk of recurrence. Traction during ESD provides better exposure of the submucosa and may allow deeper dissection, potentially reducing the risk of positive VMs. We conducted a retrospective multicenter study to compare the proportion of resections with positive VMs in ESD performed with vs. without traction in pathologically staged T1b EC. METHODS: Patients who underwent ESD revealing T1b EC (squamous or adenocarcinoma) at 10 academic tertiary referral centers in the United States (n = 9) and Brazil (n = 1) were included. Demographic and clinical data were abstracted. ESD using either traction techniques (tunneling, pocket) or traction devices (clip line, traction wire) were classified as ESD with traction (Tr-ESD) and those without were classified as ESD without traction (cESD). The primary outcome was a negative VM. Multivariable logistic regression was used to assess associations with negative VM. RESULTS: 166 patients with pathologically staged T1b EC underwent Tr-ESD (n=63, 38%) or cESD (n=103, 62%). Baseline factors were comparable between both groups. On multivariable analysis, Tr-ESD was found to be independently associated with negative VM (OR 2.25, 95% CI 1.06, 4.91, P=0.037) and R0 resection (OR 2.83, 95% CI 1.33, 6.23 P=0.008). CONCLUSION: ESD with traction seems to be associated with higher odds of negative VM than ESD without traction for pathologically staged T1b EC, and future well-conducted prospective studies are warranted to establish the findings of the current study.

International Consensus Recommendations for Safe Use of LAMS for On- and Off-Label Indications Using a Modified Delphi Process.

INTRODUCTION: The study aimed to develop international consensus recommendations on the safe use of lumen-apposing metal stents (LAMSs) for on- and off-label indications. METHODS: Based on the available literature, statements were formulated and grouped into the following categories: general safety measures, peripancreatic fluid collections, endoscopic ultrasound (EUS)-biliary drainage, EUS-gallbladder drainage, EUS-gastroenterostomy, and gastric access temporary for endoscopy. The evidence level of each statement was determined using the Grading of Recommendations Assessment, Development, and Evaluation methodology.International LAMS experts were invited to participate in a modified Delphi process. When no 80% consensus was reached, the statement was modified based on expert feedback. Statements were rejected if no consensus was reached after the third Delphi round. RESULTS: Fifty-six (93.3%) of 60 formulated statements were accepted, of which 35 (58.3%) in the first round. Consensus was reached on the optimal learning path, preprocedural imaging, the need for airway protection and essential safety measures during the procedure, such as the use of Doppler, and measurement of the distance between the gastrointestinal lumen and the target structure. Specific consensus recommendations were generated for the different LAMS indications, covering, among others, careful patient selection, the preferred size of the LAMS, the need for antibiotics, the preferred anatomic location of the LAMS, the need for coaxial pigtail placement, and the appropriate management of LAMS-related adverse events. DISCUSSION: Through a modified international Delphi process, we developed general and indication-specific experience- and evidence-based recommendations on the safe use of LAMS.

The 2022 top 10 list of endoscopy topics in medical publishing: an annual review by the American Society for Gastrointestinal Endoscopy Editorial Board.

Using a systematic literature search of original articles published during 2022 in Gastrointestinal Endoscopy and other high-impact medical and gastroenterology journals, the 10-member Editorial Board of the American Society for Gastrointestinal Endoscopy composed a list of the 10 most significant topic areas in GI endoscopy during the study year. Each Editorial Board member was directed to consider 3 criteria in generating candidate lists-significance, novelty, and global impact on clinical practice-and subject matter consensus was facilitated by the Chair through electronic voting. The 10 identified areas collectively represent advances in the following endoscopic spheres: artificial intelligence, endoscopic submucosal dissection, Barrett's esophagus, interventional EUS, endoscopic resection techniques, pancreaticobiliary endoscopy, management of acute pancreatitis, endoscopic environmental sustainability, the NordICC trial, and spiral enteroscopy. Each board member was assigned a consensus topic area around which to summarize relevant important articles, thereby generating this précis of the "top 10" endoscopic advances of 2022.

Endoscopic blind limb reduction with septotomy: a novel endoscopic approach to candy cane syndrome after Roux-en-Y gastric bypass.

Video 1The endoscopic blind limb reduction with septotomy procedure.

AGA Clinical Practice Update on the Role of Artificial Intelligence in Colon Polyp Diagnosis and Management: Commentary.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Institute Clinical Practice Update (CPU) is to review the available evidence and provide expert commentary on the current landscape of artificial intelligence in the evaluation and management of colorectal polyps. METHODS: This CPU was commissioned and approved by the AGA Institute Clinical Practice Updates Committee (CPUC) and the AGA Governing Board to provide timely guidance on a topic of high clinical importance to the AGA membership and underwent internal peer review by the CPUC and external peer review through standard procedures of Gastroenterology. This Expert Commentary incorporates important as well as recently published studies in this field, and it reflects the experiences of the authors who are experienced endoscopists with expertise in the field of artificial intelligence and colorectal polyps.

Novel devices for third-space endoscopy procedures.

Third-space endoscopy (TSE) is a subspecialty in interventional endoscopy that exploits the submucosa as a working space for the management of various gastrointestinal diseases. Over recent years, TSE has emerged as a viable alternative to surgery for the treatment of various conditions. The rapid dissemination and adoption of TSE has been largely supported by the advent of novel devices aimed to improve the efficacy and safety of these procedures. In this article, we review some of the recent developments in TSE devices and provide our initial experience with these instruments in clinical practice.

Ultrasound Assisted Endoscopic Gastric Bypass (USA-EGB): a potential endoscopic alternative to surgical bypass, a pre-clinical proof of concept study.

Background and study aims Endoscopic weight loss procedures have gained traction as minimally invasive options for the primary treatment of obesity. Thus far, we have developed endoscopic procedures that reliably address gastric restriction but result in significantly less weight loss than surgical gastrointestinal bypass. The goal of this nonsurvival study was to assess the technical feasibility of an endoscopic procedure, that incorporates both gastric restriction and potentially reversible gastrointestinal bypass. Methods Ultrasound-assisted endoscopic gastric bypass (USA-EGB) was performed in three consecutive live swine, followed by euthanasia and necropsy. Procedure steps were: 1) balloon-assisted enteroscopy that determines the length of the bypassed limb; 2) endoscopic ultrasound-guided gastroenterostomy that creates a gastrointestinal anastomosis using a lumen apposing metal stent; 3) endoscopic pyloric exclusion that disrupts transpyloric continuity resulting in complete gastrointestinal bypass; and 4) gastric restriction that reduces gastric volume. Results Complete gastrointestinal bypass and gastric restriction was achieved in all three swine. The mean total procedure time was 131 minutes (range 113-143), mean length of the bypassed limb was 92.5 cm and 180 cm, using short and long overtubes, respectively. There were no significant complications. Conclusions We successfully described USA-EGB in three consecutive live swine. Further studies are needed to access the procedures safety, efficacy, and clinical use.