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.

Global prospective case series of ERCPs using a single-use duodenoscope.

BACKGROUND: The first commercialized single-use duodenoscope was cleared by the US Food and Drug Administration in December 2019. Data regarding endoscopic retrograde cholangiopancreatography (ERCP) using a single-use duodenoscope are needed on a broader range of cases conducted by endoscopists with varying levels of experience in a wide range of geographic areas. METHODS: 61 endoscopists at 22 academic centers in 11 countries performed ERCP procedures in adult patients aged ≥ 18. Outcomes included ERCP completion for the intended indication, rate of crossover to a reusable endoscope, device performance ratings, and serious adverse events (SAEs). RESULTS: Among 551 patients, 236 (42.8 %) were aged > 65, 281 (51.0 %) were men, and 256 (46.5 %) had their procedure as an inpatient. ERCPs included 196 (35.6 %) with American Society for Gastrointestinal Endoscopy complexity of grades 3-4. A total of 529 ERCPs (96.0 %) were completed: 503 (91.3 %) using only the single-use duodenoscope, and 26 (4.7 %) with crossover to a reusable endoscope. There were 22 ERCPs (4.0 %) that were not completed, of which 11 (2.0 %) included a crossover and 11 (2.0 %) were aborted cases (no crossover). Median ERCP completion time was 24.0 minutes. Median overall satisfaction with the single-use duodenoscope was 8.0 (scale of 1 to 10 [best]). SAEs were reported in 43 patients (7.8 %), including 17 (3.1 %) who developed post-ERCP pancreatitis. CONCLUSIONS: In academic medical centers over a wide geographic distribution, endoscopists with varying levels of experience using the first marketed single-use duodenoscope had good ERCP procedural success and reported high performance ratings for this device.

Per-oral pancreatoscopy-guided lithotripsy vs. extracorporeal shock wave lithotripsy for treating refractory main pancreatic duct stones in chronic pancreatitis: Protocol for an open-label multi-center randomized clinical trial.

BACKGROUNDS/OBJECTIVES: Patients with chronic pancreatitis may develop pancreatic duct stones that can obstruct outflow leading to ductal hypertension and pain. Both endoscopic retrograde pancreatography (ERP) with per-oral pancreatoscopy (POP) and intraductal lithotripsy and extracorporeal shock wave lithotripsy (ESWL) are feasible options to attempt ductal stone clearance. This study aims to compare POP-guided lithotripsy with ESWL in the management of refractory symptomatic main pancreatic duct stones. METHODS: This is an open-label, multi-center, parallel, randomized clinical trial. Patients with chronic pancreatitis and main pancreatic duct stones ≥5 mm who fail standard ERP methods for stone removal will be eligible for this study. In total, 150 subjects will be randomized 1:1 to either ESWL or POP. A maximum of 4 sessions of either ESWL or POP will be allowed in each arm, with crossover permitted thereafter. The primary outcome is complete stone clearance and secondary outcomes include quality of life, pain scores, number of interventions, and daily opiate requirements. CONCLUSIONS: This study aims to answer the question of which lithotripsy method is superior in removing refractory pancreatic duct stones while addressing the effects of lithotripsy on quality of life and pain in patients with chronic calcific pancreatitis (ClinicalTrials.gov NCT04115826).

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.).

Digital Single-operator Cholangioscopy (DSOC) Improves Interobserver Agreement (IOA) and Accuracy for Evaluation of Indeterminate Biliary Strictures: The Monaco Classification.

BACKGROUND: Visual characteristics seen during digital single-operator cholangioscopy (DSOC) have not been validated. The aim of this 2-phase study was to define terminology by consensus for the visual diagnosis of biliary lesions to develop a model for optimization of the diagnostic performance of DSOC. MATERIALS AND METHODS: In phase 1 (criteria identification), video-cholangioscopy clips were reviewed by 12 expert biliary endoscopists, who were blinded to the final diagnosis. Visual criteria were consolidated into the following categories: (1) stricture, (2) lesion, (3) mucosal features, (4) papillary projections, (5) ulceration, (6) abnormal vessels, (7) scarring, (8) pronounced pit pattern.During the second phase (validation), 14 expert endoscopists reviewed DSOC (SpyGlass DS, Boston Scientific) clips using the 8 criteria to assess interobserver agreement (IOA) rate. RESULTS: In phase 1, consensus for visual findings were categorized into 8 criteria titled the "Monaco Classification." The frequency of criteria were: (1) presence of stricture-75%, (2) presence of lesion type-55%, (3) mucosal features-55%, (4) papillary projections-45%, (5) ulceration-42.5%, (6) abnormal vessels-10%, (7) scarring-40%, and (8) pronounced pit pattern-10%. The accuracy on final diagnosis based on visual impression alone was 70%.In phase 2, the IOA rate using Monaco Classification criteria ranged from slight to fair. The presumptive diagnosis IOA was fair (κ=0.31, SE=0.02), and overall diagnostic accuracy was 70%. CONCLUSIONS: The Monaco classification identifies 8 visual criteria for biliary lesions on single-operator digital cholangioscopy. Using the criteria, the IOA and diagnostic accuracy rate of DSOC is improved compared with prior studies.

Endoscopic Ultrasound Finding of Diffuse Echogenicity in the Pancreas, Is It Relevant?

BACKGROUND/OBJECTIVES: Diffuse echogenicity of the pancreas, a commonly discovered finding on endoscopic ultrasound (EUS), is often of undetermined significance. The goal of this study was to characterize the clinical picture and pancreatic function in patients who incidentally present with this endosonographic finding. METHODS: This was a case-control study comparing consecutive adult patients with diffuse echogenicity of the pancreas found on EUS to those who did not have known pancreas disease. Demographic and clinical data were extracted from the electronic medical record. The primary endpoint was exocrine pancreatic insufficiency (EPI) defined as fecal elastase (FE-1) < 200 µg/g. RESULTS: A total of 166 patients were included in this study. There were 89 patients who had diffuse echogenicity of the pancreas on EUS and FE-1 testing. There were 77 control patients with chronic diarrhea who did not have known pancreas disease but did have FE-1 testing. EPI was significantly more likely in the fatty pancreas group compared to the control group (47% vs 6%, p < 0.001). There was also a significantly greater proportion of smokers in the fatty pancreas group compared to the control group (42% vs 17%, p = 0.002). There were no other differences in baseline characteristics between the two groups, including prevalence of chronic pancreatitis by Rosemont classification. On multiple logistic regression analysis controlling for multiple variables, smoking (OR 2.26, 95% CI 1.15-4.43) and NAFLD (OR 3.99, 95% CI 1.09-14.70) had significant associations with EPI. CONCLUSIONS: This study found a significantly greater amount of patients who had diffuse echogenicity of the pancreas on EUS to also have EPI. This is compared to a control group of patients without known pancreas disease. This prevalence was found in the absence of a significant association with chronic pancreatitis on EUS based on Rosemont classification. Future controlled studies are required to further investigate this relationship.

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.

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.

Digital Pancreaticocholangioscopy for Mapping of Pancreaticobiliary Neoplasia: Can We Alter the Surgical Resection Margin?

INTRODUCTION: In patients with pancreaticobiliary lesions anticipating surgical resection, digital pancreaticocholangioscopy can be used to identify the extent of disease. This presurgical"mapping" could change the surgical plan and optimize patient care. MATERIALS AND METHODS: Patients with pancreaticobiliary lesions anticipating surgery who underwent endoscopic retrograde cholangiopancreatography with digital pancreaticocholangioscopy from 9 international centers were included. Primary outcome was whether pancreaticocholangioscopy altered the surgical plan. Secondary outcome was correlation between surgical and endoscopic histology and adverse events. RESULTS: A total of 118 patients were included (64% male, mean age 69 y): cholangioscopy in 105 patients (89%), pancreatoscopy in 13 patients (11%). Pancreaticocholangioscopy changed the surgical plan in 39 (34%) of patients: 8 of 13 in the pancreatic duct, 32 of 105 in the bile duct. In the bile duct, 6 patients (5%) had less extensive surgery, 26 patients (25%) avoided surgery. In the pancreatic duct, 4 patients (31%) had more extensive surgery and 4 patients (31%) had less extensive surgery. Four patients with downstaged surgery had positive margins on surgical resection; 1 required additional surgical intervention. Overall correlation between endoscopy and surgical histology was 88%. Adverse events included post endoscopic retrograde cholangiopancreatography pancreatitis in 3 patients (2.5%). CONCLUSION: Digital pancreaticocholangioscopy can be effectively used as a mapping tool to delineate the degree of involvement of biliary lesions before surgical resection, in some cases altering the surgical plan. Prospective studies are needed, especially when downstaging surgery.

Cholangioscopy Is Safe and Feasible in Elderly Patients.

BACKGROUND & AIMS: Although cholangioscopy is widely used during endoscopic retrograde cholangiopancreatiography (ERCP), its safety and feasibility for elderly patients are not well established. We aimed to evaluate the safety and feasibility of cholangioscopy in elderly patients. METHODS: We performed a retrospective study of all ERCPs with single-operator cholangioscopy (SOC) performed at 3 tertiary referral hospitals from March 2012 through October 2015. We collected data on patient demographics, procedure indications, findings, complications, and success rates (complete success was achieved if all intended diagnostic and therapeutic procedures were performed, such as tissue sample collection or complete removal of stones). The cohort was divided into 3 groups: patients younger than 65 years (group 1, n = 178), patients 65-75 years old (group 2, n = 86), and patients older than 75 years (group 3, n = 77). We used 1-way ANOVA, the χ2 test, and the Wilcoxon sum rank test to compare study variables. The primary aim was to assess rates of complications from ERCP with SOC in elderly patients compared with younger patients. RESULTS: Baseline clinical features were similar among groups, except for a higher prevalence of co-morbidities in group 3. The indication for and findings from ERCP with SOC differed among the groups; stricture or tumor was the most common indication in groups 1 and 3-the most common findings were strictures and masses, respectively. In group 2, choledocholithiasis was the most common indication and finding. The success rate, analyzed in a subset of 209 patients, was 88.5% overall and did not differ significantly among groups. The overall rate of complication was 7.33% with no significant difference among groups (7.30% for group 1, 6.98% for group 2, and 7.79% for group 3) (P < .17). CONCLUSIONS: In a retrospective analysis of ERCPs with SOCs, we found this procedure to be safe for elderly patients (older than 75 years), who had rates of complications and hospital admission similar to those of younger patients.

Efficacy and Safety of Digital Single-Operator Cholangioscopy for Difficult Biliary Stones.

BACKGROUND & AIMS: It is not clear whether digital single-operator cholangioscopy (D-SOC) with electrohydraulic and laser lithotripsy is effective in removal of difficult biliary stones. We investigated the safety and efficacy of D-SOC with electrohydraulic and laser lithotripsy in an international, multicenter study of patients with difficult biliary stones. METHODS: We performed a retrospective analysis of 407 patients (60.4% female; mean age, 64.2 years) who underwent D-SOC for difficult biliary stones at 22 tertiary centers in the United States, United Kingdom, or Korea from February 2015 through December 2016; 306 patients underwent electrohydraulic lithotripsy and 101 (24.8%) underwent laser lithotripsy. Univariate and multivariable analyses were performed to identify factors associated with technical failure and the need for more than 1 D-SOC electrohydraulic or laser lithotripsy session to clear the bile duct. RESULTS: The mean procedure time was longer in the electrohydraulic lithotripsy group (73.9 minutes) than in the laser lithotripsy group (49.9 minutes; P < .001). Ducts were completely cleared (technical success) in 97.3% of patients (96.7% of patients with electrohydraulic lithotripsy vs 99% patients with laser lithotripsy; P = .31). Ducts were cleared in a single session in 77.4% of patients (74.5% by electrohydraulic lithotripsy and 86.1% by laser lithotripsy; P = .20). Electrohydraulic or laser lithotripsy failed in 11 patients (2.7%); 8 patients were treated by surgery. Adverse events occurred in 3.7% patients and the stone was incompletely removed from 6.6% of patients. On multivariable analysis, difficult anatomy or cannulation (duodenal diverticula or altered anatomy) correlated with technical failure (odds ratio, 5.18; 95% confidence interval, 1.26-21.2; P = .02). Procedure time increased odds of more than 1 session of D-SOC electrohydraulic or laser lithotripsy (odds ratio, 1.02; 95% confidence interval, 1.01-1.03; P < .001). CONCLUSIONS: In a multicenter, international, retrospective analysis, we found D-SOC with electrohydraulic or laser lithotripsy to be effective and safe in more than 95% of patients with difficult biliary stones. Fewer than 5% of patients require additional treatment with surgery and/or extracorporeal shockwave lithotripsy to clear the duct.

Performance of a fully disposable, digital, single-operator cholangiopancreatoscope.

Background and study aim Our aim was to evaluate the first use in humans of a new, single-use, digital, single-operator intraductal cholangiopancreatoscopy system (IDCP). Patients and methods Data were collected retrospectively from four US institutions between February 2015 and April 2015. The visual impression of neoplasia or benign findings with IDCP was determined by the performing endoscopist. High grade dysplasia, intraductal papillary mucinous neoplasm, neuroendocrine tumor, and malignancy were categorized as neoplasia. Benign disease was defined as the absence of neoplasia during ≥ 6 months of follow-up. Results Patients (n = 108) with indeterminate strictures, dilatation, or difficult stones underwent IDCP. Of 74 patients with indeterminate stricture or dilatation, 29 (39 %) had neoplasia, of which 25 were confirmed by miniature biopsy forceps, 2 by surgical pathology, and 2 by the presence of metastatic disease on follow-up imaging. In patients with benign disease, 15 had concentric stenosis or normal/erythematous changes, 5 had low papillary mucosal projections, 6 had coarse granular mucosa, and 4 had nodular mucosa. Findings in patients with neoplastic disease included dilated, tortuous vessels ("tumor vessels"; n = 13), irregular margins with partial occlusion of the lumen (infiltrative stricture, n = 12), villous or nodular mass (n = 9), and finger-like villiform projections (n = 5). Operating characteristics for indeterminate stricture or dilatation were: 97 % sensitivity, 93 % specificity, 90 % positive predictive value, 98 % negative predictive value. Targeted biopsy yielded 86 % sensitivity and 100 % specificity. Stone clearance was noted in all cases. Adverse events occurred in 3 %. Conclusion The new IDCP system provides enhanced image resolution, and may improve the ability to target difficult stones and diagnose indeterminate strictures.

ERCP with per-oral pancreatoscopy-guided laser lithotripsy for calcific chronic pancreatitis: a multicenter U.S. experience.

BACKGROUND: In patients with chronic pancreatitis, laser lithotripsy (LL) permits stone fragmentation and removal during ERCP with some advantages over extracorporeal shock-wave lithotripsy (ESWL) and surgery. OBJECTIVES: To evaluate the technical success of LL in pancreatic duct (PD) stones. DESIGN: Retrospective cohort. SETTING: Four tertiary referral centers. PATIENTS: Patients undergoing endotherapy for PD stones. INTERVENTIONS: ERCP with per-oral pancreatoscopy (POP)-guided LL. MAIN OUTCOME MEASUREMENT: Technical success was defined as complete stone clearance. RESULTS: Over 3 years, 28 patients (16 men, 51 years [mean age]) underwent a median of 1 (range, 1-4) POP-LL for PD stones. Baseline parameters included pain requiring hospitalization (n=19, 68%), opiate use (n=14, 50%), or weight loss (n=11, 39%). Before POP-LL, 22 of 28 patients (79%) had a median of 1 (range, 1-5) ERCP, 9 of 28 (32%) underwent a median of 2 (range, 1-3) ESWL sessions, and 5 underwent a median of 1 (range, 1-3) POP-guided electrohydraulic lithotripsy with failed (n=2) or partial (n=3) fragmentation. A median of 2 (range, 1-3) stones sized 15 mm (range, 4-32 mm) were identified in the head (n=9, 32%), neck (n=3, 11%), body (n=9, 32%), tail (n=1, 4%), or multiple sites (n=6, 21%). Technical success occurred in 22 patients (79%) with complete clearance. Partial clearance occurred in 3 (11%). Clinical success at a median of 13 (range, 1-25) months of follow-up was noted in 25 of 28 patients (89%) by improvement in pain (n=25), decreased narcotic use (n=25), or reduced hospitalizations (n=19). Mild adverse events occurred in 8 of 28 (29%). CONCLUSIONS: POP-LL is feasible at expert centers in patients with accessible stones. Although intensive endotherapy is required, most patients achieve stone clearance and clinical improvement.

Endoscopic treatment of gastroesophageal reflux disease.

The endoscopic treatment of gastroesophageal reflux disease (GERD) has evolved significantly in the past 20 years. Current practices include devices specifically designed for GERD. Newer techniques aim to use less extra equipment, to be less costly, and to use accessories readily available in endoscopy units, as well as using standard endoscopes to apply such techniques. It is of utmost importance to properly select the patients for endoscopic therapy, and it should be done in a multidisciplinary approach.

El tratamiento endoscópico de la enfermedad por reflujo gastroesofágico (ERGE) ha evolucionado significativamente en los últimos 20 años. Las prácticas actuales incluyen dispositivos diseñados específicamente para la ERGE. Las técnicas más nuevas tienen como objetivo utilizar menos equipos adicionales, ser menos costosos y utilizar accesorios fácilmente disponibles en las unidades de endoscopia, así como utilizar endoscopios estándar para aplicar dichas técnicas. Es de suma importancia seleccionar adecuadamente a los pacientes para la terapia endoscópica, y debe hacerse en un enfoque multidisciplinario.

The Assessment of a Novel Endoscopic Ultrasound-Compatible Cryocatheter to Ablate Pancreatic Cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease that may be treated utilizing thermal therapies. Cryoablation is an effective, minimally invasive therapy that has been utilized for the treatment of various cancers, offering patients a quicker recovery and reduced side effects. Cryoablation has been utilized on a limited basis for the treatment of PDAC. With the recent reports on the success of cryoablation, there is a growing interest in the use of cryoablation as a standalone, minimally invasive procedure to treat PDAC. While offering a promising path, the application of cryoablation to PDAC is limited by current technologies. As such, there is a need for the development of new devices to support advanced treatment strategies for PDAC. To this end, this study investigated the performance of a new endoscopic ultrasound-compatible cryoablation catheter technology, FrostBite. We hypothesized that FrostBite would enable the rapid, effective, minimally invasive delivery of ultra-cold temperatures to target tissues, resulting in effective ablation via an endoscopic approach. Thermal properties and ablative efficacy were evaluated using a heat-loaded gel model, tissue-engineered models (TEMs), and an initial in vivo porcine study. Freeze protocols evaluated included single and repeat 3 and 5 min applications. Isotherm assessment revealed the generation of a 2.2 cm diameter frozen mass with the -20 °C isotherm reaching a diameter of 1.5 cm following a single 5 min freeze. TEM studies revealed the achievement of temperatures ≤ -20 °C at a diameter of 1.9 cm after a 5 min freeze. Fluorescent imaging conducted 24 h post-thaw demonstrated a uniformly shaped ellipsoidal ablative zone with a midline diameter of 2.5 cm, resulting in a total ablative volume of 6.9 cm3 after a single 5 min freeze. In vivo findings consistently demonstrated the generation of ablative areas measuring 2.03 cm × 3.2 cm. These studies demonstrate the potential of the FrostBite cryocatheter as an endoscopic ultrasound-based treatment option. The data suggest that FrostBite may provide for the rapid, effective, controllable freezing of cancerous pancreatic and liver tissues. This ablative power also offers the potential of improved safety margins via the minimally invasive nature of an endoscopic ultrasound-based approach or natural orifice transluminal endoscopic surgery (NOTES)-based approach. The results of this pre-clinical feasibility study show promise, affirming the need for further investigation into the potential of the FrostBite cryocatheter as an advanced, minimally invasive cryoablative technology.

Accurate and safe diagnosis and treatment of neoplastic biliary lesions using a novel 9F and 11F digital single-operator cholangioscope.

Background and study aims Digital single-operator cholangioscopy (DSOC) allows the diagnosis of biliary duct disorders and treatment for complicated stones. However, these technologies have limitations such as the size of the probe and working channel, excessive cost, and low image resolution. Recently, a novel DSOC system (eyeMAX, Micro-Tech, Nanjing, China) was developed to address these limitations. We aimed to evaluate the usefulness and safety of a novel 9F and 11F DSOC system in terms of neoplastic diagnostic accuracy based on visual examination, ability to evaluate tumor extension and to achieve complete biliary stone clearance, and procedure-related adverse events (AEs). Patients and methods Data from ≥ 18-year-old patients who underwent DSOC from July 2021 to April 2022 were retrospectively recovered and divided into a diagnostic and a therapeutic cohort. Results A total of 80 patients were included. In the diagnostic cohort (n = 49/80), neovascularity was identified in 26 of 49 patients (46.9%). Biopsy was performed in 65.3% patients with adequate tissue sample obtained in 96.8% of cases. Biopsy confirmed neoplasia in 23 of 32 cases. DSOC visual impression achieved 91.6% sensitivity and 87.5% specificity in diagnosing neoplasms. In the therapeutic cohort (n = 43/80), 26 of 43 patients required lithotripsy alone. Total stone removal was achieved in 71% patients in the first session. Neither early nor late AEs were documented in either the diagnostic or therapeutic cohort. Conclusions The novel DSOC device has excellent diagnostic accuracy in distinguishing neoplastic biliary lesions as well as therapeutic benefits in the context of total stone removal, with no documented AEs.

Multicenter trial evaluating the use of covered self-expanding metal stents in benign biliary strictures: time to revisit our therapeutic options?

BACKGROUND: Covered self-expanding metal stents are being used more frequently in benign biliary strictures (BBS). We report the results of a multicenter study with fully covered self-expanding metal stent (FCSEMS) placement for the management of BBS. AIM: : To prospectively evaluate the efficacy and safety of FCSEMS in the management of BBS. PATIENTS AND METHODS: Patients with BBS from 6 tertiary care centers who received FCSEMS with flared ends between April 2009 and October 2010 were included in this retrospective study.Efficacy was measured after removal of FCSEMS by evaluating stricture resolution on the basis of symptom resolution, imaging, laboratory studies, and/or choledochoscopy at removal. Safety profile was evaluated by assessing postprocedural complications. RESULTS: A total of 133 patients (78, 58.6% males) with a mean age of 59.2±14.8 years with BBS received stents. Of the 133 stents placed, 97 (72.9%) were removed after a mean stent duration of 95.5±48.7 days. Stricture resolution after FCSEMS removal was as follows: postsurgical, 11/12 (91.6%); gallstone-related disease, 16/19 (84.2%); chronic pancreatitis, 26/31 (80.7%); other etiology, 4/5 (80.0%); and anastomotic strictures, 19/31(61.2%). Ninety-four patients were included in the logistic regression analyses. Patients who had indwelling stents for >90 days were 4.3 times more likely to have resolved strictures [odds ratio, 4.3 (95% confidence interval, 1.24-15.09)] and patients with nonmigrated stents were 5.4 times more likely to have resolved strictures [odds ratio, 5.4 (95% confidence interval, 1.001-29.29)]. CONCLUSIONS: FCSEMS for BBS had an acceptable rate of stricture resolution for postsurgical strictures, gallstone-related strictures, and those due to chronic pancreatitis. Predictors for stricture resolution include longer indwell time and absence of migration. Further study is warranted to assess long-term efficacy in a prospective manner with longer than 3-month time of stent indwelling time.

Evaluation of a fully covered self-expanding metal stent with flared ends in malignant biliary obstruction: a multicenter study.

BACKGROUND AND AIMS: Limited data are available regarding fully covered metal stents in the management of malignant distal biliary strictures. The aim of this study was to evaluate the safety of a fully covered self-expanding metal stent (FCSEMS) with flared ends, in treating malignant biliary strictures. We report our long-term retrospective analysis from 6 centers. METHODS: A total of 260 patients (142 males, median age 68 y) underwent endoscopic retrograde cholangiopancreatography with placement of FCSEMS (WallFlex; Boston Scientific, Natick, MA) for the palliation of obstructive jaundice in the setting of pancreatic adenocarcinoma (169), metastatic disease (36), cholangiocarcinoma (23), ampullary cancer (19), or other (13). Patients were evaluated clinically in follow-up and biochemical tests of liver function were obtained. Data were recorded for the following variables: patient survival, duration of stent patency, the need for subsequent biliary intervention, and complications. RESULTS: A total of 266 FCSEMS were placed in 260 patients. There was a median survival of 100 days (range, 7 to 531 d). There was a mean follow-up of 134±118 days (range, 4 to 519 d). Biliary decompression was successful in 252 patients (97%). At the end of the study period, 121 were alive with a patent stent, 65 patients died with a patent stent, 40 patients were successfully bridged to surgery, 8 patients had their patent stent removed and had no need for further stenting, and 18 patients were lost to follow-up. Five patients who had a successfully placed FCSEMS were considered a failure due to the following reason: migration (2), cholangitis (1), stent occlusion (1), and removal for management of proximal biliary obstruction (1). Two additional patients experienced migration that did not require FCSEMS removal or replacement. Stent replacement was required in 10 patients, of whom 6 had a second FCSEMS placed. The remaining 4 were in the failure group and underwent replacement with either uncovered stents or plastic stents. Other complications, managed conservatively, included pain (2), postendoscopic retrograde cholangiopancreatography pancreatitis (4), fever (1), retroperitoneal perforation (1), and postsphincterotomy bleeding (1). The mean patency duration was 328 days (SE 19.04). The patency percentage was 83% at 3 months, 63% at 6 months, and 48.5% at 12 months. CONCLUSIONS: In the management of malignant distal biliary strictures, the fully covered WallFlex stent has acceptable patency and complication rates. Further long-term prospective data are required to confirm this observation.