Colonic-enteric lumen-apposing metal stents: a promising and safe alternative for endoscopic management of small-bowel obstruction.

BACKGROUND AND AIMS: Lumen-apposing metal stents (LAMSs) have revolutionized the treatment of various gastroenterologic conditions that previously required surgery. The use of LAMSs for the management of small-bowel obstruction (SBO) involves EUS-guided coloenterostomy (EUS-CE) between the colon and a dilated loop of the small intestine proximal to the point of obstruction. This procedure is potentially beneficial for patients with malignant SBO who are poor surgical candidates. METHODS: A retrospective cohort study was conducted at 2 tertiary care hospitals. Patients who underwent EUS-CE for SBO were identified, and data regarding patient demographics, indication for the procedure, location of the obstruction, procedural details, and adverse events were collected. The primary outcome was technical success of the procedure. Secondary outcomes were clinical success, resolution of symptoms, ability to tolerate enteral nutrition, and adverse events. RESULTS: Twenty-six patients who underwent the EUS-CE procedure were included. Technical success was achieved in all 26 patients, clinical success (resolution of obstructive symptoms) was achieved in 92.3% of patients (24/26), and the ability to resume enteral nutrition in 84.6% (22/26). Adverse events occurred in 4 patients (15.4%) and included bleeding (1/26), diarrhea (2/26), and postprocedure sepsis (1/26). Patients were followed for a mean of 54.8 days (range, 2-190). CONCLUSIONS: This study highlights that EUS-CE with LAMSs can be performed with high technical and clinical success for the management of SBO, particularly in patients with malignant obstructions who are not suitable candidates for surgical interventions. Further research with larger sample sizes will be essential to substantiate its efficacy and safety.

Impact of COVID-19 Infection on Pancreato-Biliary Diseases Requiring Endoscopic Retrograde Cholangiopancreatography.

BACKGROUND: Viral infections are known to impact the pancreato-biliary system; however, there are limited data showing that the same is true of COVID-19. Endoscopic retrograde cholangiopancreatography (ERCP) can safely be performed in patients with COVID-19 infection, but outcomes of patients with COVID-19 infections and concomitant pancreatic and biliary disease requiring endoscopic intervention are unknown. AIMS: This study aims to evaluate the severity of pancreaticobiliary diseases and post-ERCP outcomes in COVID-19 patients. METHODS: Patients with pancreato-biliary disease that required inpatient ERCP from five centers in the United States and South America between January 1, 2020, and October 31, 2020 were included. A representative cohort of patients from each month were randomly selected from each site. Disease severity and post-ERCP outcomes were compared between COVID-19 positive and COVID-19 negative patients. RESULTS: A total of 175 patients were included: 95 COVID positive and 80 COVID negative. Mean CTSI score for the patients who had pancreatitis was higher in COVID-positive cohort by 3.2 points (p < .00001). The COVID-positive group had more cases with severe disease (n = 41) versus the COVID-negative group (n = 2) (p < .00001). Mortality was higher in the COVID-19 positive group (19%) compared to COVID-negative group (7.5%) even though the COVID-19-negative group had higher incidence of malignancy (n = 17, 21% vs n = 7, 7.3%) (p = 0.0455). CONCLUSIONS: This study shows that patients with COVID infection have more severe pancreato-biliary disease and worse post-ERCP outcomes, including longer length of stay and higher mortality rate. These are important considerations when planning for endoscopic intervention. CLINICALTRIALS: gov: (NCT05051358).

The outcomes and safety of patients undergoing endoscopic retrograde cholangiopancreatography combining a single-use cholangioscope and a single-use duodenoscope: A multicenter retrospective international study.

BACKGROUND: Duodenoscope-related multidrug-resistant organism (MDRO) infections raise concerns. Disposable duodenoscopes have been recently introduced in the market and approved by regulatory agencies with the aim to reduce the risk of endoscopic retrograde cholangiopancreatography (ERCP) associated infections. The aim of this study was to evaluate the outcome of procedures performed with single-use duodenoscopes in patients with clinical indications to single-operator cholangiopancreatoscopy. METHODS: This is a multicenter international, retrospective study combining all patients who underwent complex biliopancreatic interventions using the combination of a single-use duodenoscope and a single-use cholangioscope. The primary outcome was technical success defined as ERCP completion for the intended clinical indication. Secondary outcomes were procedural duration, rate of cross-over to reusable duodenoscope, operator-reported satisfaction score (1 to 10) on performance rating of the single-use duodenoscope, and adverse event (AE) rate. RESULTS: A total of 66 patients (26, 39.4% female) were included in the study. ERCP was categorized according to ASGE ERCP grading system as 47 (71.2%) grade 3 and 19 (28.8%) grade 4. The technical success rate was 98.5% (65/66). Procedural duration was 64 (interquartile range 15-189) min, cross-over rate to reusable duodenoscope was 1/66 (1.5%). The satisfaction score of the single-use duodenoscope classified by the operators was 8.6 ± 1.3 points. Four patients (6.1%) experienced AEs not directly related to the single-use duodenoscope, namely 2 post-ERCP pancreatitis (PEP), 1 cholangitis and 1 bleeding. CONCLUSIONS: Single-use duodenoscope is effective, reliable and safe even in technically challenging procedures with a non-inferiority to reusable duodenoscope, making these devices a viable alternative to standard reusable equipment.

Couching of cataractous lens in microphthalmic eyes with irido-fundal coloboma: revisiting the historical technique.

PURPOSE: Cataract surgery in microphthalmic eyes is challenging due to anatomical restraints, hard bulky nucleus. This series aims to evaluate the safety and efficacy of couching of intraocular lens in irido-fundal coloboma with microphthalmos. SETTING: Tertiary care centre in South India. DESIGN: Retrospective non-comparative study in eyes with irido-fundal coloboma, corneal diameter < 7 mm and brown cataract. Visual acuity less than 6/60 in other eye. METHODS: Anterior chamber entry made, zonules broken and lens dislocated into the vitreous cavity in a controlled manner. Baseline Clinico-demographic details, corrected distance visual acuity (CDVA), Intra-ocular pressure (IOP), corneal diameter, axial length, lens status and post-surgery CDVA, IOP and complications recorded and followed up for atleast 6 months. RESULTS: Fifteen eyes of 15 subjects were evaluated with a mean age 49.4 ± 10.9 years. At baseline, mean IOP 14.5 ± 3.8 mmHg, mean axial length 19.3 ± 0.5 mm, mean corneal diameter was 6.5 ± 0.34 mm and CDVA 2 logMAR which improved to 1.5 logMAR at 3 months (p value 0.002). Transient spike in IOP in 33.3% subjects was medically managed with no significant difference in IOP (p > 0.05) at baseline (14.5 ± 3.8 mmHg), 3 months post-surgery (16 ± 2.8 mmHg) and 6 months post-surgery (14.9 ± 2.5 mmHg). One patient underwent re-couching. No other major complications were noted. CONCLUSION: Couching of cataractous lens is an effective and safe method in microphthalmic eyes with irido-fundal coloboma as last resort procedure, where no other surgical procedure may work. It provides an ambulatory gain of visual acuity in previously non-ambulatory subjects. Corneal measurements help in determining the subset of patients where couching offers viable option.

Floating Block Method for Quantum Monte Carlo Simulations.

Quantum Monte Carlo simulations are powerful and versatile tools for the quantum many-body problem. In addition to the usual calculations of energies and eigenstate observables, quantum Monte Carlo simulations can in principle be used to build fast and accurate many-body emulators using eigenvector continuation or design time-dependent Hamiltonians for adiabatic quantum computing. These new applications require something that is missing from the published literature, an efficient quantum Monte Carlo scheme for computing the inner product of ground state eigenvectors corresponding to different Hamiltonians. In this work, we introduce an algorithm called the floating block method, which solves the problem by performing Euclidean time evolution with two different Hamiltonians and interleaving the corresponding time blocks. We use the floating block method and nuclear lattice simulations to build eigenvector continuation emulators for energies of ^{4}He, ^{8}Be, ^{12}C, and ^{16}O nuclei over a range of local and nonlocal interaction couplings. From the emulator data, we identify the quantum phase transition line from a Bose gas of alpha particles to a nuclear liquid.

Artificial intelligence for diagnosing neoplasia on digital cholangioscopy: development and multicenter validation of a convolutional neural network model.

BACKGROUND: We aimed to develop a convolutional neural network (CNN) model for detecting neoplastic lesions during real-time digital single-operator cholangioscopy (DSOC) and to clinically validate the model through comparisons with DSOC expert and nonexpert endoscopists. METHODS: In this two-stage study, we first developed and validated CNN1. Then, we performed a multicenter diagnostic trial to compare four DSOC experts and nonexperts against an improved model (CNN2). Lesions were classified into neoplastic and non-neoplastic in accordance with Carlos Robles-Medranda (CRM) and Mendoza disaggregated criteria. The final diagnosis of neoplasia was based on histopathology and 12-month follow-up outcomes. RESULTS: In stage I, CNN2 achieved a mean average precision of 0.88, an intersection over the union value of 83.24 %, and a total loss of 0.0975. For clinical validation, a total of 170 videos from newly included patients were analyzed with the CNN2. Half of cases (50 %) had neoplastic lesions. This model achieved significant accuracy values for neoplastic diagnosis, with a 90.5 % sensitivity, 68.2 % specificity, and 74.0 % and 87.8 % positive and negative predictive values, respectively. The CNN2 model outperformed nonexpert #2 (area under the receiver operating characteristic curve [AUC]-CRM 0.657 vs. AUC-CNN2 0.794, P < 0.05; AUC-Mendoza 0.582 vs. AUC-CNN2 0.794, P < 0.05), nonexpert #4 (AUC-CRM 0.683 vs. AUC-CNN2 0.791, P < 0.05), and expert #4 (AUC-CRM 0.755 vs. AUC-CNN2 0.848, P < 0.05; AUC-Mendoza 0.753 vs. AUC-CNN2 0.848, P < 0.05). CONCLUSIONS: The proposed CNN model distinguished neoplastic bile duct lesions with good accuracy and outperformed two nonexpert and one expert endoscopist.

Management of Pancreatic Fluid Collections: An Evidence-based Approach.

Managing pancreatic fluid collections (PFCs) remains a challenge for many clinicians. Recently, significant progress has been made in the therapy of PFCs, including improvements in technology and devices, as well as in the development of minimally invasive endoscopic techniques, many of which are proven less traumatic when compared with surgical options and more efficacious when compared with percutaneous techniques. This review will explore latest developments in the management of PFCs and how they incorporate into the current treatment algorithm.

Endoscopic Submucosal Dissection (ESD) Offers a Safer and More Cost-effective Alternative to Transanal Endoscopic Microsurgery (TEM): An International Collaborative Study.

BACKGROUND: Endoscopic submucosal dissection (ESD) and transanal endoscopic microsurgery (TEM) are minimally invasive procedures that treat early rectal cancer (ERC). Both are effective treatments, yet there are very few studies comparing them. The aim of our study was to identify ideal candidates for each procedure. MATERIALS AND METHODS: Between January 2016 and November 2019, 204 ERC patients were managed with either ESD (n=101) or TEM (n=103) at 7 international centers. Data analyzed included clinical success, tumor characteristics, procedure info, and recurrence rates. RESULTS: Median tumor size was 40 mm±23.9 in the ESD group and 56 mm±27.9 in the TEM group, significantly larger in the latter ( P <0.00001). Average procedure time was 131.5±67.9 minutes in ESD group and 104.9±28.4 minutes in TEM group ( P =0.000347). Average hospital stay was 3.3±2.6 days in the ESD group and 4.7±0.7 days in the TEM group ( P <0.00001). Adverse event rate was 6.8% in the ESD group and 24% in the TEM group. There were no significant difference in the rate of en bloc resection, technical success, tumor location, necessity of additional procedures, and tumor recurrence rates. CONCLUSION: Compared with TEM, ESD is a safer procedure with shorter hospital stay and should be offered for patients who have ERC.

EUS-Guided Biliary Drainage Versus ERCP in Malignant Biliary Obstruction Before Hepatobiliary Surgery: An International Multicenter Comparative Study.

INTRODUCTION: Endoscopic ultrasound-guided biliary drainage (EUS-BD) is the procedure of choice for patients who cannot undergo endoscopic retrograde cholangiopancreatography (ERCP). The outcomes of patients undergoing surgery after EUS-BD for malignancy are unknown. METHODS: We conducted an international, multicenter retrospective comparative study of patients who underwent hepatobiliary surgery after having undergone EUS-BD or ERCP from 6 tertiary care centers. Patient demographics, procedural data, and follow-up care were collected in a registry. RESULTS: One hundred forty-five patients were included: EUS-BD n=58 (mean age 66, 45% male), ERCP n=87 (mean age 68, 53% male). The majority of patients had pancreatic cancer, cholangiocarcinoma, or gallbladder malignancy. In the EUS-BD group, 29 patients had hepaticogastrostomy, 24 had choledochoduodenostomy, and 5 had rendezvous technique done. The most common surgery was Whipple in both groups (n=41 EUS-BD, n=56 ERCP) followed by partial hepatectomy (n=7 EUS-BD, n=14 ERCP) and cholecystectomy (n=2 EUS-BD, n=2 ERCP). Endoscopy clinical success was comparable in both groups (98% EUS-BD, 94% ERCP). Adverse event rates were similar in both groups: EUS-BD (n=10, 17%) and ERCP (n=23, 26%). Surgery technical success and clinical success were significantly higher in the EUS-BD group compared with the ERCP group (97% vs. 83%, 97% vs. 75%). Total Hospital stay from surgery to discharge was significantly higher in the ERCP group (19 d vs. 10 d, P =0.0082). DISCUSSION: Undergoing EUS-BD versus ERCP before hepatobiliary surgery is associated with fewer repeat endoscopic interventions, shorter duration between endoscopy and surgical intervention, higher rates of surgical clinical success, and shorter length of hospital stay after surgery.

EUS-guided Gastroenterostomy: A Multicenter International Study Comparing Benign and Malignant Diseases.

BACKGROUND: Endoscopic ultrasound (EUS)-guided gastroenterostomy (EUS-GE) is a minimally invasive therapy for patients with gastric outlet obstruction without the risks of surgical bypass and the limited long-term efficacy of enteral self-expanding metal stent placement. However, due to its novelty, there is a lack of significant data comparing long-term outcomes of patients with EUS-GE, based on the underlying disease. In this study, we compare outcomes of EUS-GE on benign versus malignant indications. METHODS: Consecutive patients from 12 international, tertiary care centers who underwent EUS-GE over 3 years were extracted in a retrospective registry. Demographic characteristics, procedure-related information and follow-up data was collected. Primary outcome was the rate of adverse events associated with EUS-GE and the comparison of the rate of adverse events in benign versus malignant diseases. Secondary outcomes included technical and clinical success as well as hospitalization admission. RESULTS: A total of 103 patients were included: 72 malignant and 31 benign. The characteristics of the patients undergoing EUS-GE is shown in Table 1. The mean age of the cohort was 68 years and 58 years for malignant and benign etiology. Gender distribution was 57% and 39% being females in malignant and benign etiology group, respectively. Clinical success, technical success, average procedure time, and hospital length of stay were similar in both groups. Patients with benign underlying etiology had significantly higher number of surgically altered midgut anatomy (P=0.0379). CONCLUSION: EUS-GE is equally efficient regardless of the underlying etiology (malignant vs. benign), and the adverse events both groups were comparable.

Comparing the Safety and Efficacy of Two Commercially Available Single-Use Duodenoscopes: A Multicenter Study.

INTRODUCTION: Single-use disposable duodenoscopes (SDD) have been developed to mitigate infectious risks related to reusable duodenoscopes. The aim of this study is to compare the safety and efficacy of the two available SDDs in the United States. METHODS: We conducted a comparative study of 2 SDD in consecutive ERCP procedures performed by expert endoscopists from 9 academic centers. Performance ratings, procedure details, and adverse events were collected. RESULTS: A total of 201 patients were included: 129 patients underwent ERCP with Exalt (mean age 63, Males- 66 (51%), 72 with aScope Duodeno (mean age 65, males=30 (42%). A majority of endoscopists had performed >2000 ERCPs in both groups (71% Exalt, 93% aScope Duodeno). Technical success was 92% in both groups (n=119 Exalt-group, n=66 aScope-Duodeno-group). The procedural complexity for the ERCP cases performed were: Grade 1: 35 cases (18%), Grade 2: 83 cases (41%), Grade 3: 65 cases (32%), and Grade 4: 18 cases (9%). Thirteen patients (10%) from the Exalt group and 16 patients (22%) from the aScope Duodeno group required conversion to a reusable duodenoscope. On a scale of 1 to 5, Exalt and aScope Duodeno, respectively, were rated: 2.31 versus 2.60 for location and visualization quality, 1.38 versus 1.57 for maneuverability based on papillary orientation, 1.48 versus 1.15 for suction/air control, and 2.31 versus 2.34 for elevator efficiency. None of the adverse events were related to the SDDs. CONCLUSIONS: The 2 SDDs were comparable. Further ongoing enhancements to these devices will improve maneuverability and clinical effectiveness.

Digital single-operator cholangioscopy interobserver study using a new classification: the Mendoza Classification (with video).

BACKGROUND AND AIMS: Digital single-operator cholangioscopy (DSOC) allows direct visualization of the biliary tree for evaluation of biliary strictures. Our objective was to assess the interobserver agreement (IOA) of DSOC interpretation for indeterminate biliary strictures using newly refined criteria. METHODS: Fourteen endoscopists were asked to review an atlas of reference clips and images of 5 criteria derived from expert consensus. They then proceeded to score 50 deidentified DSOC video clips based on the visualization of tortuous and dilated vessels, irregular nodulations, raised intraductal lesions, irregular surface with or without ulcerations, and friability. The endoscopists then diagnosed the clips as neoplastic or non-neoplastic. Intraclass correlation (ICC) analysis was done to evaluate inter-rater agreement for both criteria sets and final diagnosis. RESULTS: Clips of 41 malignant lesions and 9 benign lesions were scored. Three of 5 revised criteria had almost perfect agreement. ICC was almost perfect for presence of tortuous and dilated vessels (.86), raised intraductal lesions (.90), and presence of friability (.83); substantial agreement for presence of irregular nodulations (.71); and moderate agreement for presence of irregular surface with or without ulcerations (.44). The diagnostic ICC was almost perfect for neoplastic (.90) and non-neoplastic (.90) diagnoses. The overall diagnostic accuracy using the revised criteria was 77%, ranging from 64% to 88%. CONCLUSIONS: The IOA and accuracy rate of DSOC using the new Mendoza criteria shows a significant increase of 16% and 20% compared with previous criteria. The reference atlas helps with formal training and may improve diagnostic accuracy. (Clinical trial registration number: NCT02166099.).

Safety and efficacy of a novel resection system for direct endoscopic necrosectomy of walled-off pancreas necrosis: a prospective, international, multicenter trial.

BACKGROUND AND AIMS: Direct endoscopic necrosectomy (DEN) of walled-off pancreatic necrosis (WOPN) lacks dedicated instruments and requires repetitive and cumbersome procedures. This study evaluated the safety and efficacy of a new powered endoscopic debridement (PED) system designed to simultaneously resect and remove solid debris within WOPN. METHODS: This was a single-arm, prospective, multicenter, international device trial conducted from November 2018 to August 2019 at 10 sites. Patients with WOPN ≥6 cm and ≤22 cm and with >30% solid debris were enrolled. The primary endpoint was safety through 21 days after the last DEN procedure. Efficacy outcomes included clearance of necrosis, procedural time, adequacy of debridement, number of procedures until resolution, hospital stay duration, and quality of life. RESULTS: Thirty patients (mean age, 55 years; 60% men) underwent DEN with no device-related adverse events. Of 30 patients, 15 (50%) achieved complete debridement in 1 session and 20 (67%) achieved complete debridement within 2 or fewer sessions. A median of 1.5 interventions (range, 1-7) were required. Median hospital stay was 10 days (interquartile range, 22). There was an overall reduction of 91% in percent necrosis within WOPN from baseline to follow-up and 85% in collection volume. Baseline WOPN volume was positively correlated with the total number of interventions (ρ = .363, P = .049). CONCLUSIONS: The new PED system seems to be a safe and effective treatment tool for WOPN, resulting in fewer interventions and lower hospital duration when compared with published data on using conventional instruments. Randomized controlled trials comparing the PED system with conventional DEN are needed. (Clinical trial registration number: NCT03694210.).

No Significant Difference in Post-ERCP Bleeding Rates Between Dual Antiplatelet Agents and Aspirin Alone: A Systematic Review and Meta-analysis.

BACKGROUND: Several professional society guidelines suggest holding antiplatelet agents before high-risk procedures. However, there is lack of high-grade evidence to support the recommendation as most of the studies have been single center with small sample sizes. We aimed to perform the first systematic review and meta-analysis comparing dual antiplatelet therapy (DAPT) versus aspirin alone in terms of postendoscopic retrograde cholangiopancreatography (ERCP) bleeding. METHODS: Three independent reviewers performed a comprehensive review of all original articles published from inception to May 2020, evaluating the post-ERCP bleeding rate in setting of DAPT. Primary outcomes were the overall post-ERCP bleeding rate with the use of dual antiplatelet therapy; comparison of post-ERCP bleeding rate in patients with DAPT versus aspirin alone. Secondary outcomes were comparison of immediate and delayed post-ERCP bleeding outcomes in the 2 cohorts. RESULTS: Six studies were included after a thorough search was concluded using the key words. The pooled analysis of studies revealed an overall post-ERCP bleeding rate of 5.7% (95% confidence interval: 3-10.6) on sustained DAPT. Post-ERCP bleeding in DAPT Cohort was not significantly higher as compared with aspirin only Cohort (odds ratio: 1.14, 95% confidence interval: 0.46-2.81). The immediate bleeding and delayed bleeding rates cannot be generalized due to low number of studies. CONCLUSIONS: The first systematic review and meta-analysis showed that post-ERCP bleeding rates are not significantly higher in DAPT cohort as compared with aspirin alone. Therefore, the risk of bleeding is less likely related to the antiplatelet agents and more likely related to the procedure itself.

Per Oral Endoscopic Myotomy for Zenker's Diverticulum: A Novel and Superior Technique Compared With Septotomy?

INTRODUCTION: Endoscopic management of Zenker diverticuli (ZD) has traditionally been via septotomy technique. The recent development of tunneling technique has shown to be both efficacious and safe. The aim of this study is to evaluate the tunneling technique using per oral endoscopic myotomy (Z-POEM) versus septotomy. METHODS: Patients who underwent endoscopic management of ZD either by Z-POEM or septotomy from March 2017 until November 2020 from 9 international academic centers were included. Demographics, clinical data preprocedure and postprocedure, procedure time, adverse events, and hospital length of stay were analyzed. RESULTS: A total of 101 patients (mean age 74.9 y old, 55.4% male) were included: septotomy (n=49), Z-POEM (n=52). Preprocedure Functional Oral Intake Scale score and Eckardt score was 5.3 and 5.4 for the septotomy group and 5.9 and 5.15 for the Z-POEM group. Technical success was achieved in 98% of the Z-POEM group and 100% of the septotomy group. Clinical success was achieved in 84% and 92% in the septotomy versus Z-POEM groups. Adverse events occurred in 30.6% (n=15) in septotomy group versus 9.6% (n=5) in the Z-POEM group (P=0.017). Reintervention for ongoing symptoms occurred in 7 patients in the septotomy group and 3 patients in the Z-POEM group. Mean hospital length of stay was shorter for the Z-POEM group, at 1.5 versus 1.9 days. CONCLUSIONS: A tunneling technique via the Z-POEM procedure is an efficacious and safe endoscopic treatment for ZD. Z-POEM is a safer procedure with a statistically significant reduction in adverse events compared with traditional septotomy technique.

Safety and Efficacy of Thrombin for Bleeding Gastric Varices: A Systematic Review and Meta-Analysis.

INTRODUCTION: The optimal therapy for bleeding-related gastric varices is still a controversial topic. There is a paucity of literature that comprehensively summarizes the available literature regarding safety and efficacy of thrombin in bleeding gastric varices. METHODS: Four independent reviewers performed a comprehensive review of all original articles published from inception to October 2020, describing the use of thrombin for management of bleeding gastric varices. Primary outcomes were (1) pooled early and late rebleeding rate, (2) pooled gastric variceal related mortality rate, (3) pooled rescue therapy rate, and (4) pooled adverse event rate with the use of thrombin in bleeding gastric varices. The meta-analysis was performed and the statistics were two-tailed. Finally, probability of publication bias was assessed using funnel plots and with Egger's test. RESULTS: Eleven studies were included in the analysis after comprehensive search. This yielded a pooled early rebleeding rate of 9.3% (95% CI 4.9-17) and late rebleeding rate 13.8% (95% CI 9-20.4). Pooled rescue therapy rate after injecting thrombin in bleeding gastric varices was 10.1% (95% CI 6.1-16.3). The pooled 6-week gastric variceal-related mortality rate after injecting thrombin in bleeding gastric varices was 7.6% (95% CI 4.5-12.5). There were a total of four adverse events out of a total of 222 patients with pooled adverse event rate after injecting thrombin in bleeding gastric varices was 5.6% (95% CI 2.9-10.6). CONCLUSION: In summary, the systematic review and meta-analysis on the use of thrombin for bleeding gastric varices suggest low rates of rebleeding and minimal rates of adverse events. While, early and late rebleeding rate and rescue therapy rate are similar to cyanoacrylate-based therapy, the minimal rates of adverse events are perhaps the most important benefit of thrombin. Thus, the current data suggest that thrombin is a very promising therapeutic alternative with low risk of adverse events for bleeding gastric varices.

Digital Cholangioscopic Interpretation: When North Meets the South.

BACKGROUND: Digital single-operator cholangioscopy (DSOC) (SpyGlass DS™, Boston Scientific, MA, USA) allows for high-definition imaging of the biliary tree. The superior visualization has led to the development of two different sets of criteria to evaluate and classify indeterminate biliary strictures: the Monaco criteria and the criteria in Carlos Robles-Medranda's publication (CRM). Our objective was to assess the interrater agreement (IA) of DSOC interpretation for indeterminate biliary strictures using the two newly published criteria. METHODS: Forty de-identified DSOC video recordings were sent to 15 interventional endoscopists with experience in cholangioscopy. They were asked to score the videos based on the presence of Monaco Classification criteria: stricture, lesion, mucosal changes, papillary projections, ulceration, white linear bands or rings, and vessels. Next, they scored the videos using CRM criteria: villous pattern, polypoid pattern, inflammatory pattern, flat pattern, ulcerate pattern and honeycomb pattern. The endoscopists then diagnosed the recordings as neoplastic or non-neoplastic based on the criteria. Intraclass correlation (ICC) analysis was done to evaluate interrater agreement for both criteria set and final diagnosis. RESULTS: Recordings of 26 malignant lesions and 14 benign lesions were scored. The IA using both the Monaco criteria and CRM criteria ranged from poor to excellent (range 0.1-0.76) and (range 0.1-0.62), respectively. Within the Monaco criteria, IA was excellent for lesion (0.75) and fingerlike papillary projections (0.74); good for tortuous vessels (0.7), mucosal features (0.62), uniform papillary projections (0.53), and ulceration (0.58); and fair for white linear bands (0.4). Within the CRM criteria, the IA was good for villous pattern (0.62), flat pattern (0.62), and honeycomb pattern; fair for ulcerated pattern (0.56), polypoid pattern (0.52) and inflammatory pattern (0.54). The diagnostic IA using Monaco criteria was good (0.65), while the diagnostic IA using CRM was fair (0.58). The overall diagnostic accuracy using the Monaco classification was 61% and CRM criteria were 57%. CONCLUSION: The IOA and accuracy rate of DSOC using visual criteria from both Monaco Criteria and CRM are similar. However, some criteria from both sets suffer from poor IA, thus affecting the overall diagnostic accuracy. More formal training and refinements in visual criteria with additional validation are needed to improve diagnostic accuracy. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02166099.

Convergence of Eigenvector Continuation.

Eigenvector continuation is a computational method that finds the extremal eigenvalues and eigenvectors of a Hamiltonian matrix with one or more control parameters. It does this by projection onto a subspace of eigenvectors corresponding to selected training values of the control parameters. The method has proven to be very efficient and accurate for interpolating and extrapolating eigenvectors. However, almost nothing is known about how the method converges, and its rapid convergence properties have remained mysterious. In this Letter, we present the first study of the convergence of eigenvector continuation. In order to perform the mathematical analysis, we introduce a new variant of eigenvector continuation that we call vector continuation. We first prove that eigenvector continuation and vector continuation have identical convergence properties and then analyze the convergence of vector continuation. Our analysis shows that, in general, eigenvector continuation converges more rapidly than perturbation theory. The faster convergence is achieved by eliminating a phenomenon that we call differential folding, the interference between nonorthogonal vectors appearing at different orders in perturbation theory. From our analysis we can predict how eigenvector continuation converges both inside and outside the radius of convergence of perturbation theory. While eigenvector continuation is a nonperturbative method, we show that its rate of convergence can be deduced from power series expansions of the eigenvectors. Our results also yield new insights into the nature of divergences in perturbation theory.

EUS guided pancreatic duct decompression in surgically altered anatomy or failed ERCP - A systematic review, meta-analysis and meta-regression.

INTRODUCTION: EUS-PD (EUS guided pancreatic duct drainage) is classified into two types: EUS-guided rendezvous techniques and EUS-guided PD stenting. Prior studies showed significant variation in terms of technical success, clinical success and adverse events. METHODS: Three independent reviewers performed a comprehensive review of all original articles published from inception to June 2020, describing pancreatic duct drainage utilizing EUS. Primary outcomes were technical success, clinical success of EUS-PDD and safety of EUS-PD in terms of adverse events. All meta-analysis and meta-regression tests were 2-tailed. Finally, probability of publication bias was assessed using funnel plots and with Egger's test. RESULTS: A total of sixteen studies (503 patients) described the use of EUS-PD for pancreatic duct decompression yielded a pooled technical success rate was 81.4% (95% CI 72-88.1, I 2 = 74). Meta-regression revealed that proportion of altered anatomy and method of dilation of tract explain the variance. Overall pooled clinical success rate was 84.6% (95% CI 75.4-90.8, I 2 = 50.18). Meta-regression analysis revealed that the type of pancreatic duct decompression, proportion of altered anatomy and follow up time explained the variance. Overall pooled adverse event rate was 21.3% (95% CI 16.8-26.7, I 2 = 36.6). The most common post procedure adverse event was post procedure pain. Overall pooled adverse event rate of post EUS-PD pancreatitis was 5% (95% CI 3.2-7.8, I 2 = 0). CONCLUSION: The systematic review, meta-analysis and meta-regression provides answer to the questions of the overall technical success, clinical success and the adverse event rate of EUS-PD by summarizing the available literature.

Maximizing success in single-session EUS-directed transgastric ERCP: a retrospective cohort study to identify predictive factors of stent migration.

BACKGROUND AND AIMS: EUS-directed transgastric ERCP (the EDGE procedure) is a simplified method of performing ERCP in Roux-en-Y gastric bypass patients. The EDGE procedure involves placement of a lumen-apposing metal stent (LAMS) into the excluded stomach to serve as a conduit for passage of the duodenoscope for pancreatobiliary intervention. Originally a multistep process, urgent indications for ERCP have led to the development of single-session EDGE (SS-EDGE) with LAMS placement and ERCP performed in the same session. The goal of this study was to identify predictive factors of intraprocedural LAMS migration in SS-EDGE. METHODS: We conducted a multicenter retrospective review that included 9 tertiary medical centers across the United States. Data were collected and analyzed from 128 SS-EDGE procedures. The primary outcome was intraprocedural LAMS migration. Secondary outcomes were other procedural adverse events such as bleeding and perforation. RESULTS: Eleven LAMS migrations were observed in 128 procedures (8.6%). Univariate analysis of clinically relevant variables was performed, as was a binary logistic regression analysis of stent diameter and stent dilation. This revealed that use of a smaller (15 mm) diameter LAMS was an independent predictor of intraprocedural stent migration (odds ratio, 5.36; 95% confidence interval, 1.29-22.24; P = .021). Adverse events included 3 patients who required surgery and 2 who experienced intraprocedural bleeding. CONCLUSIONS: Use of a larger-diameter LAMS is a predictive factor for a nonmigrated stent and improved procedural success in SS-EDGE. Although larger patient cohorts are needed to adequately assess these findings, performance of LAMS dilation and fixation may also decrease risk of intraprocedural LAMS migration and improve procedural success.