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.

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.

Endoscopic ultrasonography-guided deployment of embolization coils and cyanoacrylate injection in gastric varices versus coiling alone: a randomized trial.

BACKGROUND: Gastric variceal bleeding is a life-threating condition with challenging management. We aimed to compare the efficacy and safety of endoscopic ultrasonography (EUS)-guided coil embolization and cyanoacrylate injection versus EUS-guided coil embolization alone in the management of gastric varices. METHODS: A single-center, parallel-randomized controlled trial involving 60 participants with gastric varices (GOV II and IGV I) who were randomly allocated to EUS-guided coil embolization and cyanoacrylate injection (n = 30) or EUS-guided coil embolization alone (n = 30). The primary end points were the technical and clinical success rates of both procedures. The secondary end points were the reappearance of gastric varices during follow-up, along with rebleeding, the need for reintervention, and complication and survival rates. RESULTS: The technical success rate was 100 % in both groups. Immediate disappearance of varices was observed in 86.7 % of patients treated with coils and cyanoacrylate, versus 13.3 % of patients treated with coils alone (P < 0.001). Median survival time was 16.4 months with coils and cyanoacrylate versus 14.2 months with coils alone (P = 0.90). Rebleeding occurred in 3.3 % of patients treated with combined treatment and 20 % of those treated with coils alone (P = 0.04). With combined treatment, 83.3 % of patients were free from reintervention versus 60 % with coils alone (hazard ratio 0.27; 95 % confidence interval 0.095 - 0.797; P = 0.01). CONCLUSIONS: EUS-guided coil embolization with cyanoacrylate injection achieved excellent clinical success, with lower rates of rebleeding and reintervention than coil treatment alone. Multicenter studies are required to define the most appropriate technique for gastric variceal obliteration.

Safety, Feasibility, and Efficacy of Pancolonic Retroflexed Viewing Using a Short-turn Radius Colonoscope.

GOALS: The goal of this study was to evaluate the safety and feasibility of routine segmental retroflexed withdrawal viewing (RV) of the colon with the RetroView colonoscope. MATERIALS AND METHODS: This was a prospective, single-center, 2-stage diagnostic trial. After cecal intubation, mucosal evaluation by forward viewing (FV) and RV was performed by segment (right, transverse, left, and sigmoid colon, and rectum). Lesions detected during FV were removed and/or marked before retroflexion. Safety and feasibility were measured through adverse event and technical success rates. All lesions detected and removed endoscopically were recorded. RESULTS: Two hundred twenty-five patients underwent colonoscopy with the RetroView colonoscope. Retroflexion by segment was successful in the right, transverse, left, and sigmoid colon, and rectum in 98.9%, 100%, 100%, 82.6%, and 100% of cases, respectively. The mean total procedure time was 16.6 minutes. Ninety-four lesions were detected through retroflexion evaluation, for an increase in the lesions' detection rate of 30.7%. The per-adenoma miss rate of standard colonoscopy (FV) was 35.71%. The adenoma detection rate (ADR) for FV was 16%, whereas, when performing FV and RV, the ADR increased to 24.9%. Adverse events were recorded in 0.4% of cases. Therapeutic procedures were performed successfully through the retroflexed position in 81/225 patients. CONCLUSIONS: Routine retroflexion evaluation of the colonic mucosa by segment using the RetroView colonoscope is safe and feasible. Retroflexion evaluation increases the detection rate of colonic lesions behind folds, including the number of adenomas per colonoscopy and ADR, offering a complete screening colonoscopy. All therapeutic procedures are feasible through retroflexion.

Reliability and accuracy of a novel classification system using peroral cholangioscopy for the diagnosis of bile duct lesions.

BACKGROUND: The aim of this study was to propose a novel, comprehensive, macroscopic classification for bile duct lesions. METHODS: A two-stage protocol was designed. In Stage I, a retrospective study (September 2013 to September 2015) of patients with bile duct lesions detected by peroral cholangioscopy (POCS) was performed. A total of 315 images with at least 6 months of follow-up were recorded, analyzed, and correlated to histology, and were classified as non-neoplastic (one of three types, 1 - 3) or neoplastic (one of four types, 1 - 4) based on morphological and vascular patterns. In Stage II, a prospective, nonrandomized, double-blind study was performed from December 2015 to December 2016 to validate the proposed classification. Sensitivity, specificity, positive and negative predictive values (PPV and NPV, respectively), and positive and negative likelihood ratios (LR + and LR - , respectively) were calculated (gold standard: 6-month follow-up). Inter- and intraobserver agreement (kappa value, κ) among experts and non-experts were calculated. RESULTS: 171 patients were included (65 retrospective; 106 prospective). In Stage I, 28/65 cases were neoplastic and 37 /65 were non-neoplastic, according to the final diagnosis. In Stage II, 56/106 were neoplastic with a sensitivity, specificity, PPV, NPV, LR + , and LR - for neoplastic diagnosis of 96.3 %, 92.3 %, 92.9 %, 96 %, 12.52, and 0.04, respectively. The proposed classification presented high reproducibility among observers, for both neoplastic and subtypes categories. However, it was better for experts (κ > 80 %) than non-experts (κ 64.7 % - 81.9 %). CONCLUSION: The novel classification system could help physicians to distinguish non-neoplastic from neoplastic bile duct lesions.

Effect of imatinib on plasma glucose concentration in subjects with chronic myeloid leukemia and gastrointestinal stromal tumor.

BACKGROUND: Type 2 diabetes mellitus has become one of the most important public health concerns worldwide. Due to its high prevalence and morbidity, there is an avid necessity to find new therapies that slow the progression and promote the regression of the disease. Imatinib mesylate is a tyrosine kinase inhibitor that binds to the Abelson tyrosine kinase and related proteins. It enhances ß-cell survival in response to toxins and pro-inflammatory cytokine. The aim of this study is to evaluate the effect of imatinib on fasting plasma glucose in subjects with normal fasting glucose, subjects with impaired fasting glucose and in subjects with type 2 diabetes mellitus. METHODS: We identified 284 subjects diagnosed with chronic myeloid leukemia or gastrointestinal stromal tumors from the Instituto Nacional de Ciencias Medicas y Nutricion Salvador Zubiran database. 106/284 subjects were treated with imatinib. We compared the effect of imatinib on fasting plasma glucose after 1 and 6 months of treatment. We used ANOVA test of repeated samples to determine statistical significance in fasting plasma glucose before imatinib treatment and the follow-up. Statistical analysis was performed with Statistical Package for the Social Sciences v22. RESULTS: We included a total of 106 subjects: 76 with fasting plasma glucose concentrations < 100 mg/dL (normal FG), 19 subjects with fasting plasma glucose concentrations ≥100 mg/dL (impaired fasting glucose), and 11 subjects with ≥126 mg/dL (type 2 diabetes mellitus). We found a significant increase in fasting plasma glucose concentration in the normal fasting glucose group (p = 0.048), and a significant decrease in fasting plasma glucose concentration in the type 2 diabetes mellitus group (p = 0.042). In the impaired fasting glucose group, we also found a tendency towards a decrease in fasting plasma glucose (p = 0.076). We identified 11 subjects with type 2 diabetes mellitus, of whom, 7 (64%) had a reduction in their fasting plasma glucose concentrations after 6 months. A significant glycosylated hemoglobin reduction (p = 0.04) was observed. CONCLUSION: Subjects with chronic myeloid leukemia or gastrointestinal stromal tumor with type 2 diabetes mellitus had a significant reduction in fasting plasma glucose and glycosylated hemoglobin at 1 and 6 months while using imatinib.

[Ovesco clip as a rescue treatment of duodenal Dieulafoy lesion with active bleeding]. / Clip Ovesco® como tratamiento de rescate en lesión de Dieulafoy duodenal con sangrado activo.

Dieulafoy's lesions are vascular anomalies that produce gastrointestinal bleeding of the mucosa from an abnormally long and tortuous submucosal artery. It is found predominately in the stomach (80%) and less frequently in the duodenum. They constitute the 6% of all non-variceal bleeding and the 1 to 2% of all gastrointestinal bleeding source. We report a case of a 60-year-old man with hematemesis, melena and signs of hypovolemic shock with a hemoglobin level of 9 g/dL. After adequate fluid resuscitation, an upper endoscopy showed an actively bleeding Dieulafoy lesion in the second portion of the duodenum. After epinephrine injection over lesion borders, an adequate hemostasis was not achieved. An over-the-scope clip was placed. Follow-up endoscopy 24 hours later showed an effective hemostasis and the patient was discharged without complications or re-bleeding.

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.