Development of convolutional neural network models that recognize normal anatomic structures during real-time radial-array and linear-array EUS (with videos).

BACKGROUND AND AIMS: EUS is a high-skill technique that requires numerous procedures to achieve competence. However, training facilities are limited worldwide. Convolutional neural network (CNN) models have been previously implemented for object detection. We developed 2 EUS-based CNN models for normal anatomic structure recognition during real-time linear- and radial-array EUS evaluations. METHODS: The study was performed from February 2020 to June 2022. Consecutive patient videos of linear- and radial-array EUS videos were recorded. Expert endosonographers identified and labeled 20 normal anatomic structures within the videos for training and validation of the CNN models. Initial CNN models (CNNv1) were developed from 45 videos and the improved models (CNNv2) from an additional 102 videos. CNN model performance was compared with that of 2 expert endosonographers. RESULTS: CNNv1 used 45,034 linear-array EUS frames and 21,063 radial-array EUS frames. CNNv2 used 148,980 linear-array EUS frames and 128,871 radial-array EUS frames. Linear-array CNNv1 and radial-array CNNv1 achieved a 75.65% and 71.36% mean average precision (mAP) with a total loss of .19 and .18, respectively. Linear-array CNNv2 obtained an 88.7% mAP with a .06 total loss, whereas radial-array CNNv2 achieved an 83.5% mAP with a .07 total loss. CNNv2 accurately detected all studied normal anatomic structures with a >98% observed agreement during clinical validation. CONCLUSIONS: The proposed CNN models accurately recognize the normal anatomic structures in prerecorded videos and real-time EUS. Prospective trials are needed to evaluate the impact of these models on the learning curves of EUS trainees.

Assessing Endoscopic Ultrasound-Guided Radiofrequency Ablation in Unresectable Pancreatic Ductal Adenocarcinoma: A Single-Center Historic Cohort Study.

BACKGROUND: /aims: Endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has emerged as an alternative for the local treatment of unresectable pancreatic ductal adenocarcinoma (PDAC). We aim to assess the feasibility and safety of EUS-RFA in patients with unresectable PDAC. METHODS: The following was a historic cohort compounded by locally advanced (LA) and metastatic (m) PDAC naïve patients, who underwent EUS-RFA between October 2019 to March 2022. EUS-RFA was performed with a 19-g needle electrode with a 10 mm active tip for energy delivery. Study primary endpoints were feasibility, safety, and clinical follow-up; secondary endpoints were performance status (PS), local control (LC) and overall survival (OS). RESULTS: Twenty-six patients were selected: 15/26 LA-PDAC and 11/26 mPDAC. Technical success was achieved in all patients with no major adverse events. Six months after EUS-RFA, OS was 11/26 (42.3%), with significant PS improvement (P=.03). LC was achieved, with tumor reduction from 39.5 to 26 mm (P=.04). Post-treatment hypodense necrotic area was observed at six-month follow-up in 11/11 alive cases. Metastatic disease was a significant factor for OS worsening (HR 5.021; IC 95% 1.589 - 15.87; P=.004) CONCLUSIONS: EUS-RFA of pancreatic adenocarcinoma is a minimally invasive and safe technique that may have an important role as targeted therapy for local treatment of unresectable cases, as well as an alternative for poor surgical candidates. Also, RFA may play a role in downstaging cancer with potential OS increase in non-metastatic cases. Large prospective cohorts are required to evaluate this technique in clinical practice.

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).

Prophylactic EUS-guided gallbladder drainage prevents acute cholecystitis in patients with malignant biliary obstruction and cystic duct orifice involvement: a randomized trial (with video).

BACKGROUND AND AIMS: Patients with distal malignant biliary obstruction (MBO) and cystic duct orifice tumoral involvement have an increased risk for the development of acute cholecystitis after self-expandable metallic stent (SEMS) placement. We aimed to determine whether primary EUS-guided gallbladder drainage prevents acute cholecystitis in these patients. METHODS: This was a single-center, randomized control trial in patients with distal MBO enrolled from July 2018 to July 2020. Patients were randomized into 2 groups: an interventional group treated with conventional ERCP biliary drainage with SEMS placement and subsequent primary EUS-guided gallbladder drainage (EUS-GBD) and a control group treated with conventional biliary drainage alone. The primary outcome of the study was the occurrence of post-treatment acute cholecystitis, assessed for ≤12 months or until death. The secondary outcomes were hospitalization length and median survival time. RESULTS: Forty-four patients were included in the study: 22 in each group. Five patients in the control group (22.7%) and none in the intervention group experienced acute cholecystitis. The median hospitalization time was significantly lower in the interventional group than in the control group (2 days vs 1 day, P = .017). There was no difference in the observed median survival rates in the primary EUS-GBD group (2.9 months) and the control group (2.8 months) (P = .580). CONCLUSION: In this single-center study of patients with unresectable MBO and occlusion of the cystic duct orifice, prophylactic EUS-GBD demonstrated a reduced incidence of acute cholecystitis.

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.

Vascularity can distinguish neoplastic from non-neoplastic bile duct lesions during digital single-operator cholangioscopy.

BACKGROUND AND AIMS: Various macroscopic features are proposed for the diagnosis of biliary lesions during digital single-operator cholangioscopy (DSOC); however, neovasculature may be one of the most reliable features of neoplasia. We aimed to evaluate the detection of neovasculature during DSOC to distinguish neoplastic from non-neoplastic bile duct lesions. METHODS: A retrospective, single-center, cohort study was used. Neovasculature was defined as the presence of irregular or "spider" vascularity on bile duct lesions. The accuracy of detection of neovasculature for the identification of neoplastic lesions was estimated using the histologic results, surgical specimens, and/or 6-month follow-up as the criterion standard. Interobserver agreement analysis (kappa value) was performed between 2 expert endoscopists and 3 nonexpert physicians. RESULTS: Ninety-five patients were included; the median age was 65.6 years (range, 20-93 years), and 51 (53.7%) patients were female. Signs of neovasculature were observed in 65 of 95 (68.4%) patients. Histology confirmed neoplasia in 48 of 95 (50.5%) patients, and 6-month follow-up survival confirmed neoplasia in 52 of 95 (54.7%) patients. The use of vascularity for identifying neoplastic lesions achieved an accuracy of 80%, sensitivity of 94%, specificity of 63%, positive predictive value of 75%, negative predictive value of 90%, positive likelihood ratio of 2.53 (95% confidence interval, 1.71-3.76), and negative likelihood ratio of 0.09 (95% confidence interval, 0.03-0.28). The interobserver and intraobserver agreement were excellent (κ > 80%; P < .001) between expert endoscopists and nonexpert physicians. CONCLUSION: Detection of irregular or spider vascularity on bile duct lesions during DSOC evaluations accurately identifies biliary neoplastic lesions. Prospective multicenter trials are required to evaluate neovasculature as a single factor for predicting neoplasia.

Over-The-Scope Clip system as a first-line therapy for high-risk bleeding peptic ulcers: a retrospective study.

BACKGROUND: Effective hemostasis is essential to prevent rebleeding. We evaluated the efficacy and feasibility of the Over-The-Scope Clip (OTSC) system compared to combined therapy (through-the-scope clips with epinephrine injection) as a first-line endoscopic treatment for high-risk bleeding peptic ulcers. METHODS: We retrospectively analyzed data of 95 patients from a single, tertiary center and underwent either OTSC (n = 46) or combined therapy (n = 49). The primary outcome of the present study was the efficacy of the OTSC system as a first-line therapy in patients with high-risk bleeding peptic ulcers compared to combined therapy with TTS clips and epinephrine injection. The secondary outcomes included the rebleeding rate, perforation rate, mean procedure time, reintervention rate, mean procedure cost and days of hospitalization in the two study groups within 30 days of the index procedure. RESULTS: All patients achieved hemostasis within the procedure; two patients in the OTSC group and four patients in the combined therapy group developed rebleeding (p = 0.444). No patients experienced gastrointestinal perforation. OTSC had a shorter median procedure time than combined therapy (11 min versus 20 min; p < 0.001). The procedure cost was superior for OTSC compared to combined therapy ($102,000 versus $101,000; p < 0.001). We found no significant difference in the rebleeding prevention rate (95.6% versus 91.8%, p = 0.678), hospitalization days (3 days versus 4 days; p = 0.215), and hospitalization costs ($108,000 versus $240,000, p = 0.215) of the OTSC group compared to the combined therapy group. CONCLUSION: OTSC treatment is an effective and feasible first-line therapy for high-risk bleeding peptic ulcers. OTSC confers comparable costs and patient outcomes as combined treatments, with a shorter procedure time.

A rare cause of extrahepatic biliary tract stricture: a neuroendocrine carcinoma.

The case was an 82-year-old Hispanic female who complained of painless jaundice and weight loss. Endoscopic retrograde cholangiopancreatography (ERCP) showed a distal common bile duct (CBD) stricture with dilatation of the intra and extra-hepatic bile ducts.

What should be the best approach in the management of bile duct cysts in the era of cholangioscopy?

We read with great interest the scientific letter by Sánchez Melgarejo JF et al., in which they report a degenerate Todani Ia choledochal cyst in a patient with a pancreas divisum. However, patients with a choledochal cyst might benefit from per oral cholangioscopy for malignancy detection and extension evaluation.

Downhill varices: an uncommon cause of upper gastrointestinal bleeding.

BACKGROUND: Upper gastrointestinal bleeding (UGIB) is a common condition in gastroenterology, but "Downhill Varices" (DHV) or varices of the upper oesophagus are an uncommon cause of UGIB, with different aetiology from lower third oesophageal varices and different therapeutic implications. CASE REPORT: A 28-year-old male patient, with a history of chronic kidney failure secondary undergoing haemodialysis and superior vena cava syndrome (SCVS) due to multiple catheter replacements, was admitted to the Emergency Department with haematemesis secondary to a varicose vein rupture in the proximal third of oesophagus, treated initially with ethanolamine. Subsequent diagnostic studies showed the collateral circulation secondary to the SCVS. No further endoscopic or endovascular therapy could be performed and the patient will finally undergo a surgical bypass. DISCUSSION: DHVs are a very uncommon condition and endoscopic band ligation emerges as the appropriate therapeutic approach for the bleeding event. The definitive therapy continues to be that for the cause of the SVCS.

Full-depth evaluation of the bile duct with a 7F cholangioscope and its possibility for guiding therapeutics.

Background and Aims: Digital single-operator cholangioscopy (DSOC) plays a critical role in directly visualizing and treating the bile duct system. Although various cholangioscopes with different external diameters are available for DSOC, certain challenging scenarios persist in which existing scopes fail to complete a thorough evaluation of the bile ducts. To overcome these limitations, we aimed to introduce and highlight the application of a novel 7F cholangioscope. Methods: In this review article we describe the novel 7F cholangioscope, provide its assembly and setup, and review cases in which the 7F cholangioscope was used for diagnostic and therapeutic guidance. Results: Four cases involving challenging biliary assessments were presented, all of which achieved technical and clinical success. No procedure-related adverse events were reported in any of these cases. Conclusions: The 7F cholangioscope can provide additional information regarding the biliary tree and guidance for treatment, overcoming the challenging assessment of small pancreatobiliary ducts and its strictures. Its potential use in cases of severe bile duct stenosis is recommended. However, further studies evaluating safety and efficacy are needed.

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.

Use of an adapted bronchoscope for peroral endoscopic myotomy in a pediatric patient weighing less than 10 kg.

Video 1Customization of pediatric bronchoscope and peroral endoscopic myotomy settings.

EUS-guided drainage of a segment VI liver abscess using a lumen-apposing metal stent.

Video 1EUS-guided FNA and lumen-apposing metallic stent deployment.

New technologies for indeterminate biliary strictures.

An early and accurate diagnosis of biliary strictures yields optimal patient outcomes; however, endoscopic retrograde cholangiopancreatography (ERCP) with cytobrush/biopsy forceps has low sensitivity with a high number of false negatives. Various attempts to improve the accuracy of diagnosing indeterminate biliary strictures though ERCP-guided specimen acquisition have been proposed, such as with the use of fluorescence in situ hybridization, an endoscopic scraper, and the wire-grasping method, with modest to large improvements in sensitivity. Direct visualization of the biliary tree during peroral cholangioscopy has shown high sensitivity and specificity for the differentiation of neoplastic and non-neoplastic biliary lesions; however, there is no consensus on the visual characteristics of neoplastic lesions and moderate agreement between observers. Peroral cholangioscopy system (POCS)-guided specimen acquisition using forceps has shown inferior sensitivity compared to the visual characteristics; however, the specificity remains high. Optimal specimen processing with onsite evaluations and touch imprint cytology have been shown to improve the sensitivity and accurately diagnose nearly 90% of patients. In vivo evaluations of biliary strictures with probe-based confocal laser endomicroscopy have demonstrated high sensitivity with modest specificity for malignant biliary strictures. Optical computed tomography described reproductible criteria for malignancy detection in biliary strictures, increasing the sensitivity during ERCP evaluations. Differentiating benign causes from malignant causes of biliary strictures is a challenging task in clinical practice, with various concerns that still need to be addressed. Efforts should be made to define each diagnostic method's role in the evaluation of indeterminate biliary strictures.