Significance: Endoscopic optical coherence tomography (OCT) is a valuable tool for rectal imaging, enabling noninvasive visualization of transmural structures with near-histological resolution, critical for accurate tumor staging and diagnostic/therapeutic monitoring. However, anatomical variability of the rectum and the resulting changes in tissue-to-probe distance challenge optimal circumferential imaging. Aim: We aim to develop a dual-mode endoscopic OCT system, enabling real-time switching between high-detail and extended-range imaging for improved assessment of rectal wall morphology under varying anatomical conditions. Approach: A single fiber-optic ferrule containing two fibers with differing mode fields was integrated into a MHz-OCT rectoscope, enabling an extended-range mode for full circumferential imaging and a high-detail mode for close examination of fine structures with seamless live switching mechanism. The system was tested in situ on a postmortem human rectum preserved with ethanol-glycerol-lysoformin fixation. Results: Postmortem rectum imaging demonstrated the feasibility of real-time switching between the two modes. Extended-range imaging provided full circumferential coverage, whereas high-detail imaging revealed distinct rectal wall layers and fine transmural structures, validated by histological correlation. Conclusions: The dual-mode MHz-OCT system offers a flexible and practical solution for adaptive rectal imaging, providing high-resolution detail and full circumferential coverage with the potential to enhance diagnostics and treatment monitoring.

Introduction Percutaneous endoscopic gastrostomy (PEG) is a well-established and low-complication procedure for providing long-term enteral nutrition. In cases of oropharyngeal or esophageal stenosis, PEG can be safely performed using an introducer PEG. Until recently, the only established introducer PEG involved the use of gastropexy sutures. In June 2021, an alternative technique received regulatory approval. This method employs introducer PEG without prior gastropexy, securing the stomach to the abdominal wall using a tire-shaped balloon (FLOCARE DirectPEG). To date, no studies have directly compared these two techniques. The aim of this study was to prospectively evaluate and compare the procedural efficiency and clinical outcomes of gastropexy-assisted introducer PEG (gPEG) versus gastropexy-free introducer PEG (dPEG). Patients and Methods This prospective, randomized trial included patients with a confirmed indication for enteral nutrition via PEG. Eligible patients were randomized in a 1:1 ratio to receive either gPEG or dPEG. The primary endpoint was PEG placement time, measured from local skin incision to successful intragastric positioning of the tube. Secondary endpoints included total procedure time, technical feasibility, adverse events, and functional tube patency over a 30-day follow-up period. Results A total of 37 patients were enrolled, with 22 patients (59%) assigned to the gPEG group and 15 patients (41%) to the dPEG group. PEG placement time was comparable between the groups (260 ± 109 s vs. 265 ± 145 s; p  > 0.05). However, the procedural performance of gPEG was rated significantly better than that of the dPEG system (mean score 1.5 vs. 3.0; p < 0.01). In two patients (13%) in the dPEG group, the procedure had to be discontinued due to technical issues with tube deployment. Minor postprocedural complications occurred in 2 patients (9%) in the gPEG vs. in 6 patients (40%) in the dPEG ( p < 0.01). No major complications were observed. During the 30-day follow-up, tube dislocation was documented in 2 patients (9%) in the gPEG group compared to 5 patients (33%) in the dPEG group ( p = 0.0953). Tube patency was maintained in 100% of cases. Due to emerging clinically relevant differences in procedural feasibility and complication rates, the study was terminated prematurely. Conclusion In this study, the established gPEG demonstrated superior ease of use and a significantly more favorable safety profile. Based on these findings, the conventional gastropexy-assisted introducer PEG remains the preferred approach.

BACKGROUND AND AIM:Direct cholangioscopy and pancreatoscopy have become widely implemented techniques in the diagnostic and therapeutic algorithms of several pancreaticobiliary disorders. This study aimed to generate general and indication-specific European consensus recommendations on cholangioscopy and pancreatoscopy. METHODS:Supported by the available literature, statements were formulated and grouped into the following categories: (1) pre-procedural considerations, (2) general technical aspects, (3) biliopancreatic stones, (4) biliary strictures, and (5) other indications. The evidence level of each statement was determined using the GRADE methodology. Cholangioscopy experts were invited to participate in a modified Delphi process. When 80% consensus was not reached, the statement was modified based on expert feedback and subjected to an additional Delphi round. Statements were rejected if they failed to reach consensus after three Delphi rounds. RESULTS:Thirty cholangioscopy experts completed the Delphi process. Forty-two (97.6%) generated statements were accepted, of which 39 (92.9%) in the first Delphi round. 12 statements on preprocedural and periprocedural settings, 8 statements on biliopancreatic stones, 13 statements on biliary strictures, and 9 statements on other indications were accepted. CONCLUSION:Using a modified Delphi process, we developed general and indication-specific consensus recommendations for cholangioscopy to guide clinical practice.

Background:Anastomotic leakage (AL) in the upper gastrointestinal tract (uGIT) is a critical condition associated with high mortality and significant morbidity. Effective management requires prompt and specialized diagnostic and therapeutic interventions through an interdisciplinary approach. In current practice, surgical intervention is infrequent and typically reserved for cases of extensive damage. Close collaboration between radiology, endoscopy, and surgery is essential for optimal care. Endoscopic therapy is the primary modality for managing AI in the upper GIT. This review offers an overview of the most common endoscopic treatment strategies for AL in this region. Summary:Significant advancements have been made in the endoscopic management of AL in the uGIT in recent years. Endoscopic sutures and clips remain appropriate for smaller defects, but for larger leakages, endoscopic vacuum therapy (EVT) is gaining prominence over stent placement. Innovative approaches, such as vacuum stents and small diameter filmed drainage (FD), offer promising new therapeutic options for treating AL in the uGIT. Key Messages:(1) Endoscopy plays a pivotal role in the management of AL in the upper GIT. (2) A growing body of evidence supports EVT as superior to other modalities such as sutures, tissue sealants, or clips. Notably, EVT has a lower complication rate and higher healing success compared to stent therapy in AL treatment. (3) New endoscopic techniques, including the vacuum stent and FD, represent promising advancements in the treatment of AL.

BACKGROUND AND OBJECTIVE:Chromocolonoscopy significantly improves polyp/adenoma detection rates (PDR/ADR). However, its integration into routine clinical practice is hindered by its cumbersome mode of application. The objective was to develop an oral nutritional grade delivery system and to assess its efficacy for colonic release, mucosal staining and PDR/ADR as a proof of concept. METHODS:Food-grade shellac microcapsules releasing 87.5 mg of patent blue V (PBM) pH- and time-dependently were used in 35 volunteers receiving diagnostic colonoscopy either due to a positive fecal occult blood test or surveillance in inflammatory bowel disease. Six capsules were administered p.o. during the bowel preparation (Klean-Prep). Mucosal staining was assessed in total and per segment using a five-point grading scale. PDR and ADR were evaluated and compared to a propensity score-matched comparison cohort in a 1:3 ratio. RESULTS:In the PBM cohort, 97.1% (34/35) achieved an optimal to acceptable staining quality (SQ) score of ≥ 8, with a mean total score of 13.4 ± 2.9. PDR was significantly higher in the PBM group at 62.8% compared to 42.9% in the comparison group (CG; p = 0.04). ADR showed no significant differences (p = 0.06). The use of PBM resulted in a significantly increased number of detected polyps and adenomas per colonoscopy compared with CG (polyps: PMB = 1.1 ± 1.1 vs. CG = 0.6 ± 0.8, p = 0.02; adenomas: PBM = 0.8 ± 0.9 vs. CG = 0.3 ± 0.5; p = 0.02). CONCLUSION:The novel PBM demonstrated uniform mucosal staining when utilized in chromocolonoscopy. Delayed-release patent blue V appears to be a safe and effective alternative to dye-spray techniques and existing oral chromoendoscopy modalities.

We present an automated pullback mechanism for MHz-OCT rectoscopy to address non-uniform motion artifacts via consistent probe retraction. High-resolution images of a test sample demonstrate uniform frame spacing, reduced distortion, and improved imaging accuracy, validating its potential for in-vivo clinical applications. (c) 2025 The Author(s)

1: ESGE recommends the combination of endoscopic ultrasound-guided tissue acquisition (EUS-TA) and endoscopic retrograde cholangiopancreatography (ERCP)-based tissue acquisition as the preferred diagnostic approach for tissue acquisition in patients with jaundice and distal extrahepatic biliary stricture in the absence of a pancreatic mass. 2: ESGE suggests that brushing cytology should be completed along with fluoroscopy-guided biopsies, wherever technically feasible, in patients with perihilar biliary strictures. 3: ESGE suggests EUS-TA for perihilar strictures when ERCP-based modalities yield insufficient results, provided that curative resection is not feasible and/or when cross-sectional imaging has shown accessible extraluminal disease. 4: ESGE suggests using standard ERCP diagnostic modalities at index ERCP. In the case of indeterminate biliary strictures, ESGE suggests cholangioscopy-guided biopsies, in addition to standard ERCP diagnostic modalities. Additional intraductal biliary imaging modalities can be selectively used, based on clinical context, local expertise, and resource availability.

Background:Biliary leakages are notable complications that can occur following hepatobiliary surgery, traumatic injury, or iatrogenic causes related to medical interventions. The management of biliary leaks is critical as untreated leaks can result in severe complications such as biliary peritonitis, abscess formation, and sepsis. Summary:Treatment approaches for biliary leaks are highly variable and depend on the severity and anatomical location of the leak. Options range from conservative management and endoscopic interventions to surgical repair in more severe cases. A clear understanding of the classification of biliary leaks - whether anatomical, etiological, or severity-based - is essential to guide appropriate treatment strategies and improve clinical outcomes. Notably, several endoscopic techniques are now available and have significantly enhanced patient outcomes, even in complex surgical anatomies. Key Messages:The management of biliary duct leaks requires a comprehensive approach that includes endoscopic, percutaneous, and surgical interventions. The choice of treatment is determined by the severity of the leak, the patient's overall condition, and the specific context of the injury. Endoscopic retrograde cholangiopancreatography in combination with sphincterotomy and stent placement is widely regarded as the first-line treatment when the papilla is conventionally accessible.

BACKGROUND:Digital single-operator cholangioscopy (dSOC) has improved the diagnostic accuracy of indeterminate biliary duct strictures (IBDS) through targeted intraductal biopsy sampling. However, the optimal biopsy technique remains uncertain. METHODS:This international, multicenter, prospective interventional study (November 2020-August 2022) included patients with IBDS undergoing dSOC. Stricture sampling involved obtaining at least four single biopsies and at least one bite-on-bite biopsy (BBB) in all patients. Definitive diagnosis was established by pathology outcomes and 1-year clinical follow-up. The primary outcome was the accuracy of both biopsy techniques. RESULTS:89 patients were included, with 76 hilar strictures and 13 distal strictures. Technical success for obtaining adequate tissue samples was 82/89 (92.1 %) for single biopsies and 78/89 (87.6 %) for BBB. Malignancy was confirmed in 31/82 (37.8 %) and 29/78 (37.2 %) cases in single biopsies and BBB, respectively. Among 76 patients in whom both techniques were successful, pathology results were discordant in three cases (3.9 %), primarily due to understaging by BBB. Among 82 patients with complete follow-up, malignancy was confirmed in 51 (62.2 %). Sensitivity, specificity, and accuracy for malignancy or high grade dysplasia were 66.0 %, 100 %, and 78.8 % for single biopsies, and 63.8 %, 100 %, and 77.6 % for BBB, respectively. Sensitivity and accuracy were significantly decreased after stent placement or intraductal tissue acquisition during prior ERCP. The number of BBBs did not impact sensitivity or accuracy. CONCLUSIONS:BBB did not outperform at least four single biopsies for IBDS. Prior manipulation of IBDS, through stent placement or prior tissue acquisition, was associated with a decreased diagnostic yield.

QUALITY STANDARDS:Competence in cholangioscopy should be defined as the ability to successfully perform the procedure effectively, without trainer assistance, in 80 % of procedures. Cholangioscopy should be performed in endoscopy units with a high yearly volume of endoscopic retrograde cholangiopancreatographies (ERCPs) of all grades of complexity. Cholangiopancreatoscopy practice should be considered as standard or advanced as follows: - STANDARD : Cholangioscopy for extrahepatic biliary stones; evaluation of extrahepatic biliary strictures; selective ductal guidewire cannulation and removal of migrated biliary stents/foreign body extraction - ADVANCED : Cholangioscopy for intrahepatic biliary strictures or complex hepatolithiasis; percutaneous cholangioscopy and pancreatoscopy. Endoscopy units undertaking standard cholangioscopy should have prompt access to the following (on site or within a defined rapidly responsive network): - Endoscopic ultrasound (EUS)- Interventional radiology (on-site) and hepaticopancreaticobiliary (HPB) surgery - HPB multidisciplinary meetings (MDMs). Complete extrahepatic stone clearance at the initial cholangioscopy session should be successful in 80 % of intention-to-treat cases. Cholangioscopy is recommended with visually guided biopsies in the evaluation of undefined biliary strictures, ideally at index ERCP to prevent negative visual and histological effects of prior stenting; except in cases with an associated mass lesion that may allow tissue acquisition by other means (e. g. EUS or percutaneous biopsy). In cholangioscopic evaluation of extrahepatic biliary strictures, visual assessment should be achieved in > 90 % of cases, and at least 4 visually guided biopsies should be undertaken with sufficient tissue for histological assessment being obtained in > 80 % of cases. Percutaneous transhepatic cholangioscopy is indicated in patients with transhepatic bile duct access in cases of altered anatomy or failed ERCP and an indication for cholangioscopy (stone management; biliary stricture evaluation; foreign body removal). CURRICULUM FOR TRAINING:Cholangioscopy is considered an advanced adjunct to ERCP, and prior to undertaking supervised cholangioscopic procedures trainees should be competent in the basic skills of ERCP (Schutz level 1 and 2) as defined by ESGE (duodenal intubation; biliary cannulation; distal bile duct stenting; ≤ 10-mm stone extraction). Cholangioscopy training should take place in expert referral centers with a high volume of ERCP and cholangioscopy cases. A trainee's principal trainer should be an experienced trainer ideally with at least 3 years of experience in undertaking independent cholangioscopy to the determined quality standards. Competence in cholangioscopy should be defined as the ability to successfully perform the procedure effectively without trainer assistance in 80 % of procedures.

Endoscopic optical coherence tomography (OCT) offers in vivo live visualization of transmural structures with histological resolution, making it a valuable tool in medical imaging. In gastroenterology, OCT endoscopy is particularly advantageous for assessing rectal wall layers, providing superior axial and lateral resolution compared to conventional rectal endoscopic ultrasound. However, the large diameter and uneven colon surface present challenges for comprehensive imaging. Extending the OCT imaging range addresses this issue by enabling a thorough examination of the entire colon, facilitating the detection of surface polyps, tumors, and their infiltration depth. Once these regions of interest are identified, high-resolution imaging becomes essential for detailed evaluation. To meet these demands, this study integrates two different imaging modes, an extended-range mode, and a high-detail mode, within a rigid rectoscope. The extended-range mode enables visualization of deeper structures, while the high-detail mode enhances image quality for precise, contact-based assessments. The system allows seamless, real-time transitions between the modes using a 3.2 MHz-OCT system and a fiber-optic MEMS switch.

Background: Conflicting results have been published regarding the accumulation of alpha-synuclein (aSyn) pathology, in intestinal tissues of patients with Parkinson’s disease (PD). This study investigates the use of a panel of aSyn antibodies for detecting pathological aSyn in rectal biopsy samples from PD patients and healthy individuals. Materials and methods: A panel of antibodies targeting native, phosphorylated and conformation-specific forms of aSyn was used to characterize aSyn distribution in the substantia nigra and colonic tissues of controls and individuals with Lewy pathology. Distribution of aSyn was further analyzed in formalin-fixed and paraffin-embedded (FFPE) submucosal rectal biopsies of 24 PD patients and 20 healthy controls. Results: All tested antibodies valuably detected aSyn pathology in the PD substantia nigra. Native aSyn was observed at high levels in colonic tissue. The immunoreactive patterns of native aSyn, conformation-specific or phosphorylated aSyn in rectal biopsies did not show notable differences between PD patients and healthy subjects. Conclusion: The utility of immunohistochemical detection with currently commercially available antibodies for native and pathological forms of aSyn in rectal tissues appears limited. The findings advocate for the development of alternative methods to detect pathological aSyn conformers in rectal FFPE biopsies.

INTRODUCTION:Ductal decompression has become the main approach for treating patients with symptomatic chronic calcifying pancreatitis and signs of ductal hypertension. Digital single operator video pancreatoscopy (dSOVP) has shown high success rates when compared with more established techniques such as extracorporeal shock wave lithotripsy. However, there is still limited evidence on long-term clinical success and quality of life. METHODS:Patients with chronic calcifying pancreatitis who underwent digital single operator video pancreatoscopy guided electrohydraulic lithotripsy (EHL) of pancreatic duct stones with initial technical and clinical success were recruited for this retrospective, multicenter cohort study. Persistence of clinical success (defined as pain reduction > 50% in numerical rating scale [NRS]) as well as postinterventional quality of life (QOL) were retrospectively evaluated by database analysis and with QOL using the Mental and Physical Condition Scores (MCS, PCS). RESULTS:A total of 58 patients were included in the long-term follow-up conducted over 24 months. Significant and sustained pain relief was reported in 70.7% of patients (n = 41) at month 3; this effect persisted until month 24. MCS decreased from 50.36 ± 13.3 at baseline to 49.75 ± 11.1 at month 12 with no statistically significant difference (data available for 42 patients, p = 0.15). Similarly, the PCS showed no significant improvement, remaining constant at 44.9 ± 9.8 at baseline and 44.9 ± 10.8 at month 12 (p = 0.1). The overall adverse event rate was 26% (11 patients), primarily consisting of mild to moderate pancreatitis (n = 9, 22%). CONCLUSIONS:Digital single operator video pancreatoscopy guided lithotripsy was shown to be safe and effective in a long-term follow-up regarding pain control but had no significant influence on QOL. Complete stone removal seems to be the key point for long-term clinical success.