A PROTOCOLIZED MANAGEMENT OF WALLED-OFF NECROSIS (WON) REDUCES TIME TO WON RESOLUTION AND IMPROVES OUTCOMES.

BACKGROUND AND AIMS: Patients with infected or symptomatic walled-off necrosis (WON) have high morbidity and health care utilization. Despite the recent adoption of non-surgical treatment approaches, WON management remains non-algorithmic. We investigated the impact of a protocolized early necrosectomy approach compared to a non-protocolized, clinician-driven approach on important clinical outcomes. METHODS: Records were reviewed for consecutive WON patients who underwent a protocolized endoscopic drainage with a lumen apposing metal stent (LAMS) (cases), and for WON patients treated with a LAMS at the same tertiary referral center who were not managed according to the protocol (controls). The protocol required repeat cross-sectional imaging within 14 days after LAMS placement, with regularly scheduled endoscopic necrosectomy if WON diameter reduction was < 50%. Control patients were treated according to their clinician's preference without an a priori strategy. Inverse probability of treatment weighting (IPTW)-adjusted analysis was used to evaluate the influence of being in the protocolized group on time to resolution. RESULTS: 24 cases and 47 controls were included. There were no significant differences in baseline characteristics. Although numbers of endoscopies and necrosectomies were similar, cases had lower adverse event rates, shorter intensive care unit (ICU) stay, and required nutritional support for fewer days. On matched multivariate cox regression, cases had earlier WON resolution (HR 5.73, 95% CI 2.62-12.5). This was confirmed in the IPTW-adjusted analysis (HR 3.4, 95% CI 1.92-6.01). CONCLUSIONS: A protocolized strategy resulted in faster WON resolution compared to a discretionary approach without the need for additional therapeutic interventions, and with a better safety profile and decreased health care utilization.

Uncovered Versus Fully-Covered Self-Expandable Metal Stents for the Management of Distal Malignant Biliary Obstruction.

BACKGROUND AND AIM: Self-expandable metal stents (SEMS) are widely used for palliation of distal malignant biliary obstruction (dMBO). However, previous studies comparing the outcomes between uncovered (UCSEMS) and covered (FCSEMS) stents report conflicting results. This large cohort study aimed to compare the clinical outcomes between UCSEMS and FCSEMS for dMBO. METHODS: A retrospective cohort study was performed in patients with dMBO who underwent either UCSEMS or FCSEMS placement between May 2017 and May 2021. Primary outcomes were rates of clinical success, adverse events (AEs), and unplanned endoscopic reintervention. Secondary outcomes included types of AEs, intervention-free stent patency, and the management and outcomes of stent occlusion. RESULTS: The cohort included 454 patients (364 UCSEMS; 90 FCSEMS). Median follow-up duration was 9.6 months and was similar between the two groups. UCSEMS and FCSEMS had comparable clinical success (p=0.250). However, UCSEMS had significantly higher rates of AEs (33.5% vs 21.1%; p=0.023) and unplanned endoscopic reintervention (27.0% vs 11.1%; p=0.002). UCSEMS had a higher rate of stent occlusion (26.9% vs. 8.9%; p<0.001) and shorter median time to stent occlusion (4.4 vs 10.7 months; p=0.002). Stent reintervention free survival was higher in the FCSEMS group. FCSEMS had a significantly higher rate of stent migration (7.8% vs 1.1%; p<0.001), but similar rates of cholecystitis (0.3% vs 1.1%; p=0.872) and post-ERCP pancreatitis (6.3% vs 6.6%; p=0.90). When UCSEMS did occlude, placement of a coaxial plastic stent had a higher rate of stent re-occlusion compared to coaxial SEMS placement (46.7% vs 19.7%; p=0.007). CONCLUSION: FCSEMS should be considered for the palliation of dMBO due to lower rates of AEs, longer patency rates, and lower rates of unplanned endoscopic intervention.

With a little help from my friends: percutaneously assisted internalization of a biliary drain.

Video 1Narrated case of an EUS-guided hepaticogastrostomy facilitated by opacification and distention of the left intrahepatic ducts using an existing percutaneous drain tract.

Endoscopic ultrasound-guided gastroenterostomy for the management of gastric outlet obstruction: A large comparative study with long-term follow-up.

Background and study aims Gastric outlet obstruction (GOO) is traditionally managed with surgical gastroenterostomy (surgical-GE) and enteral stenting (ES). Endoscopic ultrasound-guided gastroenterostomy (EUS-GE) is now a third option. Large studies assessing their relative risks and benefits with adequate follow-up are lacking. We conducted a comparative analysis of patients who underwent EUS-GE, ES, or surgical-GE for GOO. Patients and methods In this retrospective comparative cohort study, consecutive patients presenting with GOO who underwent EUS-GE, ES, or surgical-GE at two academic institutions were reviewed and independently cross-edited to ensure accurate reporting. The primary outcome was need for reintervention. Secondary outcomes were technical and clinical success, length of hospital stay (LOS), and adverse events (AEs). Results A total of 436 patients (232 EUS-GE, 131 ES, 73 surgical-GE) were included. The median duration of follow-up of the entire cohort was 185.5 days (interquartile range 55.25-454.25 days). The rate of reintervention in the EUS-GE group was lower than in the ES and surgical-GE groups (0.9 %, 12.2 %, and 13.7 %, P  < 0.0001). Technical success was achieved in 98.3 %, 99.2 %, and 100 % ( P  = 0.58), and clinical success was achieved in 98.3 %, 91.6 %, and 90.4 % ( P  < 0.0001) in the EUS-GE, ES, and surgical-GE groups, respectively. The EUS-GE group had a shorter LOS (2 days vs. 3 days vs. 5 days, P  < 0.0001) and a lower AE rate than the ES and surgical-GE groups (8.6 % vs. 38.9 % vs. 27.4 %, P  < 0.0001). Conclusion This large cohort study demonstrates the safety and palliation durability of EUS-GE as an alternative strategy for GOO palliation in select patients.

Correction to: Endoscopic Ultrasound-Guided Gastrojejunostomy for Superior Mesenteric Artery Syndrome Secondary to Rapid Weight Loss.

[This corrects the article DOI: 10.14309/crj.0000000000000868.].

Lumen-apposing metal stents for the treatment of benign gastrointestinal tract strictures: a single-center experience and proposed treatment algorithm.

BACKGROUND: Lumen-apposing metal stents (LAMS) are an alternative therapeutic option for benign gastrointestinal (GI) tract strictures. Our study aimed to evaluate the safety and efficacy of LAMS for the management of benign GI strictures. METHODS: Consecutive patients who underwent a LAMS placement for benign luminal GI strictures at a tertiary care center between January 2014 and July 2021 were reviewed. Primary outcomes included technical success, early clinical success, and adverse events (AEs). Other outcomes included rates of stent migration and re-intervention after LAMS removal. RESULTS: One hundred and nine patients who underwent 128 LAMS placements (67.9% female, mean age of 54.3 ± 14.2 years) were included, and 70.6% of the patients had failed prior endoscopic treatments. The majority of strictures (83.5%) were anastomotic, and the most common stricture site was the gastrojejunal anastomosis (65.9%). Technical success was achieved in 100% of procedures, while early clinical success was achieved in 98.4%. The overall stent-related AE rate was 25%. The migration rate was 27.3% (35/128). Of these, five stents were successfully repositioned endoscopically. The median stent dwell time was 119 days [interquartile range (IQR) 68-189 days], and the median follow-up duration was 668.5 days [IQR: 285.5-1441.5 days]. The re-intervention rate after LAMS removal was 58.3%. CONCLUSIONS: LAMS is an effective therapeutic option for benign GI strictures, offering high technical and early clinical success. However, the re-intervention rate after LAMS removal was high. In select cases, using LAMS placement as destination therapy with close surveillance is a reasonable option.

Endoscopic Ultrasound-Guided Gastrojejunostomy for Superior Mesenteric Artery Syndrome Secondary to Rapid Weight Loss.

A 19-year-old man diagnosed with diffuse large B-cell lymphoma undergoing chemotherapy presented for recurrent emesis and weight loss. Imaging studies of the abdomen demonstrated features of superior mesenteric artery syndrome. The patient deferred conservative treatment options and was deemed not to be a surgical candidate. Endoscopic ultrasound-guided gastroenterostomy using a lumen-apposing metal stent was performed to bypass the obstruction. Subsequently, the patient's oral intake and weight significantly improved. The stent was removed 6 months after placement with resolution of superior mesenteric artery syndrome symptoms.

A NOVEL CLASSIFICATION SYSTEM FOR WALLED-OFF NECROSIS: A STEP TOWARD STANDARDIZED NOMENCLATURE AND RISK STRATIFICATION FRAMEWORK.

BACKGROUND AND AIMS: The optimal therapeutic approach for walled off necrosis (WON) is not fully understood, given the lack of validated classification system. We propose a novel and robust classification system based on radiologic and clinical factors to standardize the nomenclature, provide a framework to guide comparative effectiveness trials, and inform the optimal WON interventional approach. METHODS: This was a retrospective analysis of patients who underwent endoscopic management of WON by lumen apposing metal stent (LAMS) at a tertiary referral center. Patients were classified according to the proposed "QNI" classification system: Quadrant ("Q") represented abdominal quadrant distribution, "N" denoted percent necrosis of WON. "I" indicated infection denoted as positive blood culture and/or systemic inflammatory response syndrome (SIRS) reaction with positive WON culture. Two blinded reviewers classified all patients according to the QNI system. Patients were then divided into two groups: Group 1 with lower QNI stratification (≤2 quadrants and ≤30% necrosis) vs Group 2 with a higher stratification (≥3 quadrants, 2 quadrants with ≥30% necrosis, or 1 quadrant with >60% necrosis and infection). The primary outcome was mean time to WON resolution. Secondary procedural and clinical outcomes between the groups were compared. RESULTS: Seventy-one patients (75% males) were included and stratified by the QNI classification, group 1 contained 17 patients and group 2 contained 54 patients. Patients in group 2 demonstrated higher number of necrosectomies, longer hospital stay, and more readmissions. The mean time to resolution (days) was longer in group 2 than group 1 (79.6 ± 7.76 days vs 48.4 ± 9.22 days, p=0.02). Mortality rate was higher in group 2 (15% vs. 0%, p=0.18). CONCLUSION: Despite the heterogeneous nature of WON in severe acute pancreatitis, a proposed QNI system may provide a standardized framework for WON classification to inform clinical trials, risk-stratify disease course, and potentially inform optimal management approach.

Percutaneous transluminal angioplasty balloons for endoscopic ultrasound-guided pancreatic duct interventions.

BACKGROUND: Endoscopic ultrasound (EUS)-guided main pancreatic duct (PD) access may be used when conventional endoscopic retrograde cholangiopancreatography (ERCP) techniques fail. The use of a percutaneous transluminal angioplasty balloon (PTAB), originally developed for vascular interventions, can be used to facilitate transmural (e.g., transgastric) PD access and to dilate high-grade pancreatic strictures. AIM: To describe the technique, efficacy, and safety of PTABs for EUS-guided PD interventions. METHODS: Patients who underwent EUS with use of a PTAB from March 2011 to August 2021 were retrospectively identified from a tertiary care medical center supply database. PTABs included 3-4 French angioplasty catheters with 3-4 mm balloons designed to use over a 0.018-inch guidewire. The primary outcome was technical success. Secondary outcomes included incidence of adverse events (AEs) and need for early reintervention. RESULTS: A total of 23 patients were identified (48% female, mean age 55.8 years). Chronic pancreatitis was the underlying etiology in 13 (56.5%) patients, surgically altered anatomy (SAA) with stricture in 7 (30.4%), and SAA with post-operative leak in 3 (13.0%). Technical success was achieved in 20 (87%) cases. Overall AE rate was 26% (n = 6). All AEs were mild and included 1 pancreatic duct leak, 2 cases of post-procedure pancreatitis, and 3 admissions for post-procedural pain. No patients required early re-intervention. CONCLUSION: EUS-guided use of PTABs for PD access and/or stricture management is feasible with an acceptable safety profile and can be considered in patients when conventional ERCP cannulation fails.

Histological assessment of new cholangioscopy-guided forceps in ERCP biliary stricture sampling: a blinded comparative study.

Background and study aims Obtaining quality tissue during ERCP biliary stricture sampling is of paramount importance for a timely diagnosis. While single-operator cholangioscopy (SOC)-guided biopsies have been suggested to be the superior biliary tissue acquisition modality given direct tissue visualization, less is known about the specimen histological quality. We aimed to analyze the specimen quality of SOC biopsies and compare the new generation forceps with prior "legacy" forceps. Patients and methods Patients who underwent SOC from January 2017-August 2021 for biliary sampling were reviewed. In February 2020, the SOC-guided biopsy forceps were changed from legacy SpyBite to the SpyBite Max forceps (max). Specimens were assessed by blinded pathologists for crush artifact (none, mild, or severe) and gross size (greatest dimension in mm). Crush artifact and gross size were compared between the two groups. The diagnostic performance characteristics for cholangiocarcinoma (CCA), were assessed in an exploratory fashion. Results Eighty-one patients (max = 27, legacy = 54) with similar baseline characteristics were included in this study. On blinded pathological assessment, 58 % had crush artifact, without significant differences between the two groups (Max 63 % vs. Legacy 56 %; P  = 0.64). A similar mean specimen size was found (max 3 mm vs. legacy 3.2 mm; P  = 0.24). The overall prevalence of CCA was 40 %. The sensitivity, specificity, positive predictive value, and negative predictive value of the entire cohort using a combination of cytology, fluorescence in situ hybridization, and SOC-guided biopsies were 78.1 %, 91.8 %, 86.2 %, and 86.5 %, respectively. No difference between legacy or max groups was found. Conclusions A high rate of crush artifact was found in SOC-guided biopsy specimens. Further investigation regarding proper biopsy technique and handling is necessary to increase the diagnostic yield with SOC-guided biopsies.

Identification of patients with malignant biliary strictures using a cholangioscopy-based deep learning artificial intelligence (with video).

BACKGROUND AND AIMS: Accurate diagnosis of malignant biliary strictures as being benign or malignant remains challenging. Previously, it has been suggested that direct visualization and interpretation of cholangioscopy images has greater accuracy for stricture classification than current sampling techniques (i.e., brush cytology and forceps biopsy) via endoscopic retrograde cholangiopancreatography (ERCP). We aimed to develop a convolutional neural network (CNN) model capable of accurate stricture classification and real-time evaluation based solely on cholangioscopy image analysis. DESIGN: Consecutive patients with cholangioscopy examinations from 2012 to 2021 were reviewed. A CNN was developed and tested using cholangioscopy images with direct expert annotations. The CNN was then applied to a multicenter, reserved test set of cholangioscopy videos. CNN performance was then directly compared to that of ERCP sampling techniques. Occlusion block heatmap analyses were used to evaluate and rank cholangioscopy features associated with malignant biliary strictures. RESULTS: A total of 154 patients with available cholangioscopy examinations were included in the study. The final image database was comprised of 2,388,439 still images. The CNN demonstrated good performance when tasked with mimicking expert annotations of high-quality malignant images (AUROC 0.941). Overall accuracy of CNN-based video analysis (0.906) was significantly greater than that of brush cytology (0.625; p = 0.04) or forceps biopsy (0.609; p =0.03). Occlusion block heatmap analysis demonstrated that the most frequent image feature for a malignant biliary stricture was the presence of frond-like mucosa/papillary projections. CONCLUSION: This study demonstrates that a CNN developed using cholangioscopy data alone has greater accuracy for biliary stricture classification than traditional ERCP-based sampling techniques.

AGA Clinical Practice Update on the Endoscopic Approach to Recurrent Acute and Chronic Pancreatitis: Expert Review.

DESCRIPTION: The purpose of this American Gastroenterological Association (AGA) Clinical Practice Update Expert Review is to provide practical, evidence-based guidance to clinicians regarding the role of endoscopy for recurrent acute and chronic pancreatitis. METHODS: This expert review was commissioned and approved by the AGA Institute Clinical Practice Updates Committee and the AGA Governing Board to provide guidance on a topic of clinical importance to the AGA membership, underwent internal peer review by the Clinical Practice Updates Committee (CPUC), and external peer review through standard procedures of Gastroenterology. This review is framed around the 8 best practice advice points agreed upon by the authors, based on the results of randomized controlled trials, observational studies, systematic reviews and meta-analyses, as well expert consensus in this field. Best Practice Advice Statements BEST PRACTICE ADVICE 1: After an unrevealing initial evaluation, endoscopic ultrasound is the preferred diagnostic test for unexplained acute and recurrent pancreatitis. Magnetic resonance imaging with contrast and cholangiopancreatography is a reasonable complementary or alternative test to endoscopic ultrasound, based on local expertise and availability. BEST PRACTICE ADVICE 2: The role of endoscopic retrograde cholangiopancreatography (ERCP) for reducing the frequency of acute pancreatitis episodes in patients with pancreas divisum is controversial, but minor papilla endotherapy may be considered, particularly for those with objective signs of outflow obstruction, such as a dilated dorsal pancreatic duct and/or santorinicele. There is no role for ERCP to treat pain alone in patients with pancreas divisum. BEST PRACTICE ADVICE 3: The role of ERCP for reducing the frequency of pancreatitis episodes in patients with unexplained recurrent acute pancreatitis and standard pancreatic ductal anatomy is controversial and should only be considered after a comprehensive discussion of the uncertain benefits and potentially severe procedure-related adverse events. When pursued, ERCP with biliary sphincterotomy alone may be preferable to dual sphincterotomy. BEST PRACTICE ADVICE 4: Surgical intervention should be considered over endoscopic therapy for long-term treatment of patients with painful obstructive chronic pancreatitis. Endoscopic intervention is a reasonable alternative to surgery for suboptimal operative candidates or those who favor a less invasive approach, assuming they are clearly informed that the best practice advice primarily favors surgery. BEST PRACTICE ADVICE 5: When ERCP is pursued, small (≤5mm) main pancreatic duct stones can be treated with pancreatography and conventional stone extraction maneuvers. For larger stones, extracorporeal shockwave lithotripsy and/or pancreatoscopy with intraductal lithotripsy may be required. BEST PRACTICE ADVICE 6: When ERCP is pursued, prolonged stent therapy (6-12 months) is effective for treating symptoms and remodeling main pancreatic duct strictures. The preferred approach is to place and sequentially add multiple plastic stents in parallel (upsizing); emerging evidence suggests that fully covered self-expanding metal stents may have a role for this indication, but additional research is necessary. BEST PRACTICE ADVICE 7: ERCP with stent insertion is the preferred treatment for benign biliary stricture due to chronic pancreatitis. FCSEMS placement is favored over multiple plastic stents whenever feasible, given similar efficacy but significantly reduced need for stent exchange procedures during the treatment course. BEST PRACTICE ADVICE 8: Celiac plexus block should not be routinely performed for the management of pain due to chronic pancreatitis. The decision to proceed with celiac plexus block in selected patients with debilitating pain in whom other therapeutic measures have failed can be considered on a case-by-case basis, but only after discussion of the unclear outcomes of this intervention and its procedural risks.

EUS-Guided hepaticogastrostomy in a pregnant patient with Roux-en-Y hepaticojejunostomy anatomy.

Video 1EUS-Guided hepaticogastrostomy in a pregnant patient with Roux-en-Y hepaticojejunostomy anatomy.