Introduction

Visceral artery pseudoaneurysms typically originate from the splanchnic circulation, often as a result of inflammation, trauma, or infection. If left untreated, these pseudoaneurysms carry a near 100% mortality rate. Endovascular intervention by interventional radiologists is currently the preferred treatment approach. The role of endoscopic ultrasonography (EUS)-assisted interventions in managing visceral pseudoaneurysms is an evolving area of clinical practice.

Aims & Methods

In this retrospective single-centre study conducted between January 2020 to December 2024, the technical and clinical success of EUS-guided embolisation of visceral arterial pseudoaneurysms was assessed. Technical success was defined as absence of blood flow on color doppler imaging after successful placement of coil or in combination with thrombin. Clinical success was defined as the absence of re-bleeding or pseudoaneurysm recurrence during a follow-up period of 12 weeks.

Results

A total of 26 patients (88.46% males) were included, selected based on computed tomography angiography (CTA). EUS could not visualize pseudoaneurysms in two patients, thus EUS-guided intervention could be performed successfully in 24/26 patients, yielding a technical success rate of 92.30%. The median age of the study population was 33 years (IQR 25-42). The most common underlying condition was pancreatitis, with chronic pancreatitis affecting 17/26 patients (65.38%) and acute pancreatitis affecting 7/26 patients (26.92%). The splenic artery was the most frequently involved (13/26 patients, 50%), followed by the gastroduodenal artery (9/26 patients, 34.61%). The median size of the pseudoaneurysms was 1.5 cm (IQR 1-2.6 cm). Clinical success was achieved in 20/24 patients (83.33%). Despite technical success, three patients experienced early re-bleeding. Two patients were managed with rescue procedures, while one patient succumbed to bleed despite rescue intervention. One patient had a recurrence of pseudoaneurysm.

Conclusion

EUS-guided embolization using coil, alone or in combination with thrombin, is a safe and effective method for managing visceral arterial pseudoaneurysms, even as a first-line intervention. This approach warrants further validation in larger cohorts and its direct comparison with the endovascular approach.

Disclosure

No Conflict of Interest

Introduction

Distal malignant biliary obstruction (dMBO) is a frequently occurring condition that requires immediate intervention. The primary treatment for dMBO comprises endoscopic retrograde cholangiopancreatography (ERCP) with biliary stent insertion^​. The European Society of Gastrointestinal Endoscopy recommends the use of self-expandable metal stents (SEMS) for palliative drainage of dMBO because of their superior patency and reduced incidence of adverse events (AEs), including recurrent biliary obstruction, compared to those of plastic stents^​. Three types of SEMS are available: uncovered SEMS (UCSEMS), fully covered SEMS (FCSEMS), and partially covered SEMS. However, the ideal stent type for palliative drainage of dMBO remains undetermined. Several studies have compared UCSEMS with FCSEMS to determine which type is most appropriate for dMBO^​. In terms of patency, some prospective trials have shown that FCSEMS result in better outcomes^​; however, others have observed similar results with UCSEMS and FCSEMS^​. Most studies have primarily focused on pancreatic cancer cases; however, the pathophysiology of pancreatic cancer and that of nonpancreatic cancer differ significantly, resulting in inconsistent outcomes. Post-ERCP pancreatitis (PEP) is the most common and serious AE associated with the transpapillary placement of SEMS, with an incidence rate of up to 10.8%^​. Therefore, studies have aimed to identify the risk factors for PEP after SEMS placement. Compared to UCSEMS placement, FCSEMS placement may be more strongly linked to a higher risk of PEP because they block the pancreatic duct orifice more effectively. Additionally, nonpancreatic cancer has been identified as a potential risk factor for PEP^​. Therefore, FCSEMS placement for nonpancreatic cancer cases is associated with a significantly higher risk of PEP. We examined the safety of UCSEMS for dMBO caused by nonpancreatic cancer and observed a low PEP rate, even for nonpancreatic cancer cases^​. However, a comparison of UCSEMS and FCSEMS is still required because no studies have evaluated their use for dMBO caused by nonpancreatic cancer. Therefore, this study evaluated the efficacy and safety of UCSEMS and FCSEMS for palliative drainage of dMBO caused by nonpancreatic cancer.

Aims & Methods

This retrospective multicenter study included patients who underwent UCSEMS or FCSEMS placement for nonpancreatic cancer-induced dMBO at four centers between January 2010 and April 2024. Propensity score matching (1:1) of the UCSEMS and FCSEMS groups was performed. Technical and clinical success, AEs, recurrent biliary obstruction (RBO), time to RBO (TRBO), and overall survival (OS) of these groups were compared.

Results

No significant differences in technical success (100% for both), clinical success (100% for both), and TRBO (median: 311 days [UCSEMS] vs. 317 days [FCSEMS]; p=0.42) were observed between groups. Similarly, OS did not differ significantly (median: 432 days [UCSEMS] vs. 190 days [FCSEMS]; p=0.083). The incidence of postendoscopic retrograde cholangiopancreatography pancreatitis (PEP) of the UCSEMS group was significantly lower than that of the FCSEMS group (4.2% vs. 33%; p=0.023).

Conclusion

compared to FCSEMS, UCSEMS provided sufficient patency and reduced AEs associated with dMBO caused by nonpancreatic cancer. The cause of dMBO should be carefully considered when choosing the optimal stent. UCSEMS may be safer and more effective than FCSEMS for the treatment of nonpancreatic cancer cases.

Disclosure

Authors declare no conflict of interests for this article.

Introduction

Hirschsprung’s disease is caused by the absence of ganglia in the deep intestinal wall, leading to dysfunction [1]. Resection of the affected area is the only cure, so accurate margin detection is essential. Currently, intraoperative rapid pathology is used, requiring tissue sampling and staining, but each test takes over 30 min and may need multiple samples, sometimes delaying decisions up to 3 h. A quick on-site method to detect ganglia around 200 μm deep is needed.
Various methods, including confocal microscopy [2], have been studied, but issues remain, such as dye toxicity and limited depth (>200 μm) imaging.

Aims & Methods

For non-destructive and stain-free visualization of tissues, we focused on Near-Infrared Hyperspectral Imaging (NIR-HSI)[3][4]. Near-infrared light—particularly in the 1000–1400 nm range—exhibits high tissue penetrability and is effective for detecting deep tissues. In addition, the near-infrared region provides spectroscopic information based on molecular vibrations, enabling component analysis. NIR-HSI holds promise for the identification of cancer and other biological tissues without the need for fluorescence or external marking [4][5].
To implement NIR-HSI, we developed a novel microscopic optical system capable of guiding near-infrared light. The near-infrared light source, which combines a supercontinuum light source and an acousto-optic tunable filter, allows for the selection of arbitrary wavelengths and irradiation of the target by adjusting the applied voltage [6]. This configuration enables the acquisition of near-infrared spectral images (NIR-HSI) at arbitrary wavelengths.
For performance validation, ex vivo experiments were carried out using mouse intestine in which the nerve plexus was selectively labeled with GFP (Green Fluorescent Protein). In these experiments, near-infrared light ranging from 850 to 1400 nm was irradiated in 10-nm increments, and 77 spectral images were captured. As a reference, GFP fluorescence images were acquired in the same field of view as the near-infrared images. Based on the fluorescence images, annotations were performed to delineate the enteric nerve plexus, and near-infrared spectra were obtained from both the nerve and non-nerve regions. Furthermore, using pixel-wise spectral data, segmentation of the nerve regions was performed with a machine learning model, and the accuracy of identification was evaluated.

Results

The NIR images captured by the system showed nerve distributions and mesh-like patterns similar to those in the GFP images. Spectral differences were observed between nerve and non-nerve regions. This likely reflects tissue composition differences, as muscle tissue has higher transmittance and nerve tissue higher reflectance in the NIR range [4][5][6].
Segmentation based on spectral data successfully extracted nerve contours and distribution patterns, achieving ~80% classification accuracy.

Conclusion

To enable non-invasive, label-free visualization of deep nerve distributions, we developed a NIR-HSI microscope by integrating near-infrared hyperspectral imaging with a microscopic optical system. In mouse intestine experiments, spectral differences were observed between enteric nerve plexus and surrounding tissue. The results suggest that mesh-like nerve structures can be estimated and outlined using NIR images alone. Future work will focus on imaging human samples.

References

1. Taguchi, T.et al., “The incidence and outcome of allied disorders of Hirschsprung's disease in Japan: Results from a nationwide survey,” Asian Journal of Surgery, vol.40-1, pp.29-34, 2017.
2. Kobayashi, M., Sumiyama, K., Shimojima, N., Ieiri, S., Okano, H., Kamba, S., Fujimura, T., Hirobe, S., Kuroda, T. and Takahashi‐Fujigasaki, J., “Technical Feasibility of Visualizing Myenteric Plexus Using Confocal Laser Endomicroscopy,” Journal of Gastroenterology and Hepatology, vol.32(9), pp.1604-10, 2017.
3. S. Hayashi et al., “Near-Infrared Multispectral Imaging Rigid Endoscope System for High-Speed Target Identification Using LED Rotating Light Source”, Advanced Biomedical Engineering , Vol.14, pp.79-88, 2025.
4. Akbari, H et al., “Cancer detection using infrared hyperspectral imaging”, Cancer Science, Vol. 102, No.4, pp.852–857, 2011
5. Afromowitz,et al., “Multispectral imaging of burn wounds: a new clinical instrument for evaluating burn depth”, IEEE Transactions on Biomedical Engineering, Vol35, No.10, pp.842-850, 1988.
6. R. Fukushima et al., “Detection of Exposed Nerves in Two Individuals In Vivo and Unexposed Nerves Ex Vivo with Near-Infrared Hyperspectral Laparoscope,” 2024IEEE/SICE International Symposium on System Integration (SII), Ha Long, Vietnam, pp. 19-24, 2024.

Introduction

Pain in chronic pancreatitis (CP) varies between patients in pattern, severity, and psychological impact. CP pain assessment has been focused on intensity, missing the complexity. To address the importance of multidimensional pain evaluations, we aimed to identify pain phenotypes based on multidimensional pain assessments and examine their association with clinical factors.

Aims & Methods

We studied 248 patients with painful CP from Asia, Europe, and the USA. A cluster analysis was performed on patients with painful CP, including five pain dimensions from the COMPAT-SF questionnaire (severity, fluctuation, provocative factors, spreading pain, and qualitative descriptors). The resulting clusters were compared based on demographics and clinical data, including patient-reported outcomes and quantitative sensory testing.

Results

		Cluster 1	Cluster 2	Cluster 3	p-value​
Questionnaires	Quality of life	66.3 (22.5)	64.8 (27.7)	51.1 (24.6)	<0.001
	Catastrophizing	10.7 (11.2)	19.1 (12.4)	24.3 (13.0)	<0.001
	Anxiety	5.3 (4.1)	6.2 (4.2)	8.7 (4.5)	<0.001
	Depression	4.3 (4.3)	5.5 (4.6)	7.3 (4.7)	<0.001
	Sleep	5.0 (3.5)	5.9 (3.8)	7.5 (4.5)	<0.001
QST	PPDT sum, kPa	2284 (997)	1811.5 (574.6)	1640.1 (600.4)	<0.001
	PPTT sum, kPa	2909.6 (1247.3)	2227.1 (691.3)	2184.9 (903.2)	<0.001
	Temporal summation, abdomen	1.7 (1.8)	1.9 (1.5)	1.4 (1.8)	0.178
	CPM (%)	2.3 (18.3)	5.1 (23.7)	7.2 (17.7)	0.135

Three distinct pain phenotypes were identified in the cluster analysis. Cluster 1 (n=73) included patients with low-severity pain; Cluster 2 (n=80) was characterized by severe, fluctuating pain; and Cluster 3 (n=95) comprised patients reporting constant, severe pain. Patients in Clusters 1 and 2 reported low scores across the remaining dimensions, whereas Cluster 3 consistently scored higher. Quality of life and sleep were best in Cluster 1, declined in Cluster 2, and were lowest in Cluster 3 (both p<0.001). Scores for anxiety, depression, and catastrophizing increased progressively across clusters (all p<0.001). Sensory testing revealed a pattern of increasing hyperalgesia, with Cluster 3 showing the most pronounced responses (p<0.001).

Conclusion

The COMPAT-SF questionnaire identifies three pain phenotypes in CP. Greater pain severity and persistence correlate with increased hyperalgesia, higher psychological distress, and worse overall well-being.

Clinical Case Summary

A 37-year-old woman with a history of heavy alcohol use (3–4 bottles of wine weekly) presented with abdominal pain and haematemesis. She had experienced intermittent abdominal pain for two years. On assessment, she was stable apart from mild tachycardia and epigastric tenderness; melaena was confirmed on rectal exam. Blood tests revealed severe anaemia (Haemoglobin "Hb" 40 g/L from a baseline of 154 g/L). Gastroscopy showed severe oesophagitis without active bleeding. Abdominal CT showed a hyperdense focus in the neck of the pancreas, raising suspicion of a neuroendocrine tumour. After blood transfusion, she was discharged (Hb 73 g/L) with plans for outpatient colonoscopy and endoscopic ultrasound (EUS) to characterise the pancreatic neck lesion.
Two days later, she was readmitted with recurrent haematemesis and a Hb drop to 56 g/L. She was stabilized and discharged again. The day after her discharge, she underwent an EUS examination in our unit. The EUS revealed signs indicative of chronic pancreatitis, as well as a thick-walled vascular structure measuring 20 mm, adjacent to the head of the pancreas. This structure appeared to originate from a posterior branch of the gastroduodenal artery, and was consistent with a pseudo-aneurysm eroding into the wall of the duodenum. A subsequent triple phase CT scan showed an increase in the size of the hyperdense focus in the neck of the pancreas, raising concern for a pseudoaneurysm near the pancreaticoduodenal artery. Following these findings, the patient underwent successful coil embolization of the pseudoaneurysm.
Conclusion: In patients with chronic alcohol use, upper gastrointestinal bleeding (UGIB) may arise from complications of pancreatitis, such as pseudoaneurysm formation, rather than solely intraluminal causes. This case highlights the need for early identification and intervention in such rare but potentially life-threatening conditions.

Clinical Case Summary

A 51-year-old male presented to the emergency department with acute back pain, suspicious for renal colic. An abdominal CT scan incidentally revealed a 30 mm hypodense lesion in the pancreatic uncinate process with central calcifications (see Fig. 1).
An endoscopic ultrasound (EUS) demonstrated a hypoechoic, heterogeneous mass in the uncinate process, with irregular margins and a huge posterior acoustic shadowing. No signs of vascular or ductal involvement were noted. Therefore, EUS-guided fine needle biopsy (FNB) with a 22-G Franseen-tip needle was performed via transduodenal and transgastric approaches, obtaining an adequate histological sample after macroscopic on-site examination (MOSE).
Histological analysis revealed spindle cells positive for CD34, BCL2, STAT6, and CD99, and negative for CKIT, DOG1, desmin, actin, S100, and cytokeratins, with Ki-67 index > 5%, suggesting for solitary fibrous tumor (SFT) of the pancreas (see Fig.2). Immunohistochemical confirmation was obtained at a tertiary referral pathology laboratory. A multidisciplinary tumor board advised conservative follow-up based on the benign histology and absence of local invasion.
Conclusion: Pancreatic SFTs are extremely rare, with only 34 cases reported to date. They are more frequently located in the pancreatic head and are slightly more common in females. Most are discovered incidentally. This case highlights the critical diagnostic value of EUS-FNB, which enabled accurate tissue acquisition for advanced immunohistochemical analysis, informing a non-surgical, surveillance-based approach. Because of the non-specific clinical presentation and radiological features of pancreatic SFTs, diagnosis is particularly challenging using preoperative imaging and laboratory tests alone. Therefore, histopathological and immunohistochemical evaluation is essential for definitive diagnosis.

References

References and Illustrative Material:

Figure 1: Abdominal CT scan showing a pancreatic mass in the uncinate process with central calcification.

Figure 2: On the left, tissue sample stained with hematoxylin and eosin. Spindle cell proliferation with disorganized architecture. The lesion is hypercellular, composed of elongated mesenchymal cells with scant cytoplasm and oval-to-tapered nuclei, suggesting a spindle cell neoplasm, such as SFT. On the right, the same tissue sample was analyzed using immunohistochemistry: strong and diffuse nuclear positivity for STAT6 was found in tumor cells.

Selected References:

1. Ronchi A et al. Solitary fibrous tumors: an update on diagnosis and management. Pathol Oncol Res.

2020;26(2):597-605.

2. Wang WW, Zhou SP, Wu X, Wang LL, Ruan Y, Lu J, Li HL, Ni XL, Qiu LL, Zhou XH. Imaging, pathology, and diagnosis of solitary fibrous tumor of the pancreas: A case report and review of literature. World Journal of Clinical Cases. 2024;12(5):995–1003.

Introduction

There is increasing recognition that effective resident training in gastrointestinal endoscopy should be provided by endoscopists who have received formal educational training in the teaching of endoscopy.¹ While the implementation of Training the Colonoscopy Trainers (TCT) courses has led to significant improvements in colonoscopy quality outcomes^2,3 and polyp detection rates,⁴ evidence regarding the impact of TCT participation on teaching performance and resident learning – both of which are main goals of faculty development initiatives – is still lacking. Therefore, the aim of the present study was to evaluate the effectiveness of TCT course implementation using Kirkpatrick’s model of training evaluation.

Aims & Methods

In this study, 24 gastroenterologists from a university hospital and two affiliated general teaching hospitals in the north-eastern educational region of the Netherlands, participated in a two-day TCT course. The course was evaluated at three levels of Kirkpatrick’s model: (a) post-course evaluations reflecting the initial reaction; (b) video analysis of endoscopy training in the workplace before and after the TCT course using the mini-Structured Training Trainer Assessment Report (mini-STTAR); (c) a post-course resident survey reflecting the impact on the home-environment. Descriptive statistics and non-parametric tests were used to analyse the effectiveness of the TCT course.

Results

The TCT course was well received by participants, they highlighted the use of a structured training framework as a strength. Video analysis of endoscopy training in the workplace demonstrated a significant improvement in post-course trainer performance, both at 1-3 months (T1) and 6-9 months (T2). Significant improvements were found in the overall mini-STTAR scores (p<0.001), and across most mini-STTAR items, particularly in the items related to the phase preceding the actual training (referred to as the Set) and the evaluation after completion of the training (referred to as the Closure). Regarding the actual training (referred to as the Dialogue), participants demonstrated a significant positive change in ‘guiding/deconstructing’ and ‘controlling’ (both at T1 and T2) and in ‘encouraging/praise’ (only at T2). Participants received significantly higher 5-point Likert scale ratings as ‘excellent trainer’ at T1 (mean 4.13) and T2 (mean 4.29), compared to baseline (mean 3.58, p<0.001). In the post-course survey, all residents (N=16) were satisfied with the supervision of endoscopy trainers in their teaching hospitals. Nine (56%) reported uniform endoscopy supervision among trainers, a significant increase compared to a pre-course resident survey (8%, p=0.034).⁵ Although residents reported that the frequency of a didactic Set and Closure did not increase, most respondents indicated that the implementation of the TCT course improved the setting of learning objectives, the provision of spontaneous feedback, guidance during difficult endoscopies, and the prevention of undesired scope takeover.

Conclusion

The implementation of a TCT course provided a structured and useful training framework, and enhanced trainer performance, particularly in the didactic pre- and post-endoscopy training discussions, as well as in guiding, controlling, encouraging, and providing spontaneous feedback during the training of residents in gastrointestinal endoscopy.

References

1. Antonelli G, Voiosu AM, Pawlak KM, et al. Training in basic gastrointestinal endoscopic procedures: a European Society of Gastrointestinal Endoscopy (ESGE) and European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) Position Statement. Endoscopy. 2024;56:131-150
2. Waschke KA, Anderson J, Macintosh D et al. Training the gastrointestinal endoscopy trainer. Best Pract Res Clin Gastroenterol. 2016;30:409-419
3. Gavin DR, Valori RM, Anderson JT, et al. The national colonoscopy audit: a nationwide assessment of the quality and safety of colonoscopy in the UK. Gut. 2013;62:242-249
4. Hoff G, Botteri E, Huppertz-Hauss G, et al. The effect of train-the-colonoscopy-trainer course on colonoscopy quality indicators. Endoscopy. 2021;53:1229-1234
5. Mousset RA, de Vos Tot Nederveen Cappel WH, Pierie JEN et al. Endoscopy training in the Netherlands: a national survey among gastroenterology residents. Endosc Int Open. 2022;10:E1548-E1554