Capsule endoscopy and panendoscopy: A journey to the future of gastrointestinal endoscopy.

In 2000, the small bowel capsule revolutionized the management of patients with small bowel disorders. Currently, the technological development achieved by the new models of double-headed endoscopic capsules, as miniaturized devices to evaluate the small bowel and colon [pan-intestinal capsule endoscopy (PCE)], makes this non-invasive procedure a disruptive concept for the management of patients with digestive disorders. This technology is expected to identify which patients will require conventional invasive endoscopic procedures (colonoscopy or balloon-assisted enteroscopy), based on the lesions detected by the capsule, i.e., those with an indication for biopsies or endoscopic treatment. The use of PCE in patients with inflammatory bowel diseases, namely Crohn's disease, as well as in patients with iron deficiency anaemia and/or overt gastrointestinal (GI) bleeding, after a non-diagnostic upper endoscopy (esophagogastroduodenoscopy), enables an effective, safe and comfortable way to identify patients with relevant lesions, who should undergo subsequent invasive endoscopic procedures. The recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract, is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract, from mouth-to-anus, meeting the expectations of the early developers of capsule endoscopy.

Confocal laser endomicroscopy as predictive biomarker of clinical and endoscopic efficacy of vedolizumab in ulcerative colitis: The DETECT study.

AIMS: In patients with ulcerative colitis (UC), no biomarker is available to help the physician to choose the most suitable biotherapy. The primary objective of this pilot study was to assess the feasibility of identification of α4ß7- and TNF-expressing cells, to predict the response to vedolizumab using confocal laser endoscopy (CLE). METHODS: Patients with moderate-to-severe UC, naïve of biotherapy, received vedolizumab. Clinical evaluation was performed at each infusion. Endoscopic evaluation was performed before inclusion and at week 22. Fresh colonic biopsies were stained using FITC-labelled vedolizumab and Alexa fluor-labelled adalimumab and ex vivo dual-band CLE images were acquired. Blood samples were collected to measure trough concentrations of vedolizumab and to determine absolute counts of T and B cells subpopulations, NK cells and monocytes. RESULTS: Nineteen patients were enrolled in the study and received at least one dose of vedolizumab. Clinical remission and endoscopic improvement were observed in 58% of whom 5 patients (45%) had an endoscopic subscore of 0. In terms of clinical response and remission, endoscopic improvement and histologic response, FITC-conjugated vedolizumab staining tended to be higher in responder patients compared to non-responders at week 22. A threshold value of 6 positive FITC-vedolizumab staining areas detected by CLE seemed informative to discriminate the responders and non-responders. The results were similar in terms of clinical remission and endoscopic improvement with a sensitivity of 78% and a specificity of 85% (p = 0.05). Trough concentrations and blood immune cells were not associated with responses to vedolizumab. CONCLUSION: This pilot study demonstrate that dual-band CLE is feasible to detect α4ß7- and TNF-expressing cells. Positive α4ß7 staining seems to be associated with clinical and endoscopic remission in UC patients treated by anti-α4ß7-integrin, subject to validation by larger-scale studies. Clinical-trial.gov: NCT02878083.

Endoscopic diagnosis of gastric and oesophageal cancer in Lusaka, Zambia: a retrospective analysis.

INTRODUCTION: There are uncertainties surrounding the spectrum of upper gastrointestinal (UGI) diseases in sub-Saharan Africa. This is mainly due to the limitations of data collection and recording. We previously reported an audit of UGI endoscopic diagnoses in Zambia spanning from 1977 to 2014. We now have extended this analysis to include subsequent years, in order to provide a more comprehensive picture of how the diagnoses have evolved over 4 decades. METHODS: We combined data collected from the endoscopy unit at the University Teaching Hospital (UTH) in Lusaka during a previous review with that collected from the beginning of 2015 to the end of 2021. Since 2015, an electronic data base of endoscopy reports at the UTH was kept. The electronic data base was composed of drop-down menus that allowed for standardised reporting of findings. Collected data were coded by two experienced endoscopists and analysed. RESULTS: In total, the analysis included 25,849 endoscopic records covering 43 years. The number of endoscopic procedures performed per year increased drastically in 2010. With the exception of the last 2 years, the proportion of normal endoscopies also increased during the time under review. In total, the number of gastric cancer (GC) cases was 658 (3%) while that of oesophageal cancer (OC) was 1168 (5%). The number of GC and OC diagnoses increased significantly over the period under review, (p < 0.001 for both). For OC the increase remained significant when analysed as a percentage of all procedures performed (p < 0.001). Gastric ulcers (GU) were diagnosed in 2095 (8%) cases, duodenal ulcers (DU) in 2276 (9%) cases and 239 (1%) had both ulcer types. DU diagnosis showed a significantly decreasing trend over each decade (p < 0.001) while GU followed an increasing trend (p < 0.001). CONCLUSIONS: UGI endoscopic findings in Lusaka, Zambia, have evolved over the past four decades with a significant increase of OC and GU diagnoses. Reasons for these observations are yet to be established.

Application of the convolution neural network in determining the depth of invasion of gastrointestinal cancer: a systematic review and meta-analysis.

BACKGROUND: With the development of endoscopic technology, endoscopic submucosal dissection (ESD) has been widely used in the treatment of gastrointestinal tumors. It is necessary to evaluate the depth of tumor invasion before the application of ESD. The convolution neural network (CNN) is a type of artificial intelligence that has the potential to assist in the classification of the depth of invasion in endoscopic images. This meta-analysis aimed to evaluate the performance of CNN in determining the depth of invasion of gastrointestinal tumors. METHODS: A search on PubMed, Web of Science, and SinoMed was performed to collect the original publications about the use of CNN in determining the depth of invasion of gastrointestinal neoplasms. Pooled sensitivity and specificity were calculated using an exact binominal rendition of the bivariate mixed-effects regression model. I2 was used for the evaluation of heterogeneity. RESULTS: A total of 17 articles were included; the pooled sensitivity was 84% (95% CI, 0.81-0.88), specificity was 91% (95% CI, 0.85-0.94), and the area under the curve (AUC) was 0.93 (95% CI, 0.90-0.95). The performance of CNN was significantly better than that of endoscopists (AUC: 0.93 vs 0.83, respectively; P = .0005). CONCLUSION: Our review revealed that CNN is one of the most effective methods of endoscopy to evaluate the depth of invasion of early gastrointestinal tumors, which has the potential to work as a remarkable tool for clinical endoscopists to make decisions on whether the lesion is feasible for endoscopic treatment.

Robustness evaluation of deep neural networks for endoscopic image analysis: Insights and strategies.

Computer-aided detection and diagnosis systems (CADe/CADx) in endoscopy are commonly trained using high-quality imagery, which is not representative for the heterogeneous input typically encountered in clinical practice. In endoscopy, the image quality heavily relies on both the skills and experience of the endoscopist and the specifications of the system used for screening. Factors such as poor illumination, motion blur, and specific post-processing settings can significantly alter the quality and general appearance of these images. This so-called domain gap between the data used for developing the system and the data it encounters after deployment, and the impact it has on the performance of deep neural networks (DNNs) supportive endoscopic CAD systems remains largely unexplored. As many of such systems, for e.g. polyp detection, are already being rolled out in clinical practice, this poses severe patient risks in particularly community hospitals, where both the imaging equipment and experience are subject to considerable variation. Therefore, this study aims to evaluate the impact of this domain gap on the clinical performance of CADe/CADx for various endoscopic applications. For this, we leverage two publicly available data sets (KVASIR-SEG and GIANA) and two in-house data sets. We investigate the performance of commonly-used DNN architectures under synthetic, clinically calibrated image degradations and on a prospectively collected dataset including 342 endoscopic images of lower subjective quality. Additionally, we assess the influence of DNN architecture and complexity, data augmentation, and pretraining techniques for improved robustness. The results reveal a considerable decline in performance of 11.6% (±1.5) as compared to the reference, within the clinically calibrated boundaries of image degradations. Nevertheless, employing more advanced DNN architectures and self-supervised in-domain pre-training effectively mitigate this drop to 7.7% (±2.03). Additionally, these enhancements yield the highest performance on the manually collected test set including images with lower subjective quality. By comprehensively assessing the robustness of popular DNN architectures and training strategies across multiple datasets, this study provides valuable insights into their performance and limitations for endoscopic applications. The findings highlight the importance of including robustness evaluation when developing DNNs for endoscopy applications and propose strategies to mitigate performance loss.

Targeted multispectral filter array design for the optimization of endoscopic cancer detection in the gastrointestinal tract.

Significance: Color differences between healthy and diseased tissue in the gastrointestinal (GI) tract are detected visually by clinicians during white light endoscopy; however, the earliest signs of cancer are often just a slightly different shade of pink compared to healthy tissue making it hard to detect. Improving contrast in endoscopy is important for early detection of disease in the GI tract during routine screening and surveillance. Aim: We aim to target alternative colors for imaging to improve contrast using custom multispectral filter arrays (MSFAs) that could be deployed in an endoscopic "chip-on-tip" configuration. Approach: Using an open-source toolbox, Opti-MSFA, we examined the optimal design of MSFAs for early cancer detection in the GI tract. The toolbox was first extended to use additional classification models (k-nearest neighbor, support vector machine, and spectral angle mapper). Using input spectral data from published clinical trials examining the esophagus and colon, we optimized the design of MSFAs with three to nine different bands. Results: We examined the variation of the spectral and spatial classification accuracies as a function of the number of bands. The MSFA configurations tested showed good classification accuracies when compared to the full hyperspectral data available from the clinical spectra used in these studies. Conclusion: The ability to retain good classification accuracies with a reduced number of spectral bands could enable the future deployment of multispectral imaging in an endoscopic chip-on-tip configuration using simplified MSFA hardware. Further studies using an expanded clinical dataset are needed to confirm these findings.

Characterization of primary small intestinal lymphoma: a retrospective study based on double balloon endoscopy.

BACKGROUND: The diagnosis of primary small intestinal lymphoma (PSIL) is difficult. This study aimed to evaluate the clinical, radiological and endoscopic characteristics of PSIL and provide clue for diagnosis. METHODS: A total of 30 patients diagnosed with PSIL who underwent double balloon endoscopy (DBE) in the First Affiliated Hospital of Zhejiang University were retrospectively analyzed. Clinical, radiological and endoscopic data were collected. Univariate analysis was used to determine significant indicators for differentiating three main subtypes of PSIL. Cox regression analysis was performed to assess the risk factors for survival. RESULTS: In this study, 10 patients were pathologically diagnosed as diffuse large B-cell lymphoma (DLBCL), 11 were indolent B-cell lymphoma (BCL) and 9 were T-cell lymphoma (TCL). Compared with DLBCL patients, the body mass index (BMI) of TCL patients was significantly lower (p = 0.004). Meanwhile, compared with patients with DLBCL, the patients with indolent BCL had lower levels of C-reactive protein, lactate dehydrogenase (LDH), fibrinogen and D-Dimer (p = 0.004, p = 0.004, p = 0.006, and p = 0.002, respectively), and lower proportion of thicker intestinal wall and aneurysmal dilation in CT scan (p = 0.003 and p = 0.020, respectively). In terms of ulcer morphology, patients with DLBCL had significantly higher proportion of deep ulcers than patients with indolent BCL (p = 0.020, respectively). Cox regression analysis showed that drink (p = 0.034), concomitant colonic ulcers (p = 0.034) and elevated LDH (p = 0.043) are risk factors for mortality in patients with PSIL. CONCLUSIONS: This study provides clinical characteristics of patients with PSIL. Thicker intestinal wall and aneurismal dilation detected on CT scan and deeper ulcer on DBE examination helps to establish a diagnosis of DLBCL.

How-I-do-it: laparoscopic intragastric submucosal dissection (LISD) for gastric and gastro-oesophageal junction early lesions.

PURPOSE: Laparoscopic intragastric submucosal dissection (LISD) is a novel approach to the resection of gastric lesion that are not amenable to conventional endoscopic approaches. The technique permits favourable access to lesions situated at the cardia and angular notch of the stomach, enables en-bloc resection of large areas of tissue, and can prevent the need of formal gastrectomy or oesophagectomy in selected patients. METHODS: All cases were deemed suitable for LISD by a multidisciplinary team panel following endoscopic assessment (using white light enhancement, chromoendoscopy and magnification endoscopy) that was integrated when needed with EUS, CT scan or PET scan. The surgical technique consisted in a 3-port laparoscopic approach; after establishment of pneumoperitoneum, three gastrotomies were performed to enable port insertion into the stomach. Following establishment of stable pneumogastrium, the area of interest was identified, submucosal hyaluronic acid injection performed to provide a cushion in the plane of dissection, and the excision area was circumferentially marked with cautery. Resection was completed using cautery hook, along a plane parallel to the muscolaris propria. After the specimen was extracted in a retrieval bag, intracorporeal single layer running suture closure of gastrotomies was performed. The abdominal wall closed by layers and tap block performed along with local anaesthetic injection on skin incision. Measures were taken to ensure correct orientation of resected specimens prior to fixation. RESULTS: During the study period that spans from 2014 and 2022, a total of 11 patients underwent LISD for limited lesions of the stomach, 10 were located at gastro-oesophageal junction and one at the angular incisura. Four patients were female, seven males. The median age was 74 (46-79) years. R0 resection rate was 54.5%. Mean operative time was 109 min with very low blood loss (10 ml). Mortality rate was 0%, no immediate major complications (Grade II-V Clavien Dindo), including haemorrhage or perforation, occurred in these cases. Two patients developed dysphagia later that was successfully treated with endoscopic balloon dilatations. Median hospital stay was 3 days and median oral intake was on day 1 post-procedural. CONCLUSIONS: Laparoscopic intragastric submucosal dissection is shown to be a safe and effective intervention for the treatment of early gastric cancers in selected patients having undergone deemed not amenable for endoscopic submucosal resection for their technically challenging location. Its application can serve as route to avoid formal surgery and the associated morbidity.

Improving image classification of gastrointestinal endoscopy using curriculum self-supervised learning.

Endoscopy, a widely used medical procedure for examining the gastrointestinal (GI) tract to detect potential disorders, poses challenges in manual diagnosis due to non-specific symptoms and difficulties in accessing affected areas. While supervised machine learning models have proven effective in assisting clinical diagnosis of GI disorders, the scarcity of image-label pairs created by medical experts limits their availability. To address these limitations, we propose a curriculum self-supervised learning framework inspired by human curriculum learning. Our approach leverages the HyperKvasir dataset, which comprises 100k unlabeled GI images for pre-training and 10k labeled GI images for fine-tuning. By adopting our proposed method, we achieved an impressive top-1 accuracy of 88.92% and an F1 score of 73.39%. This represents a 2.1% increase over vanilla SimSiam for the top-1 accuracy and a 1.9% increase for the F1 score. The combination of self-supervised learning and a curriculum-based approach demonstrates the efficacy of our framework in advancing the diagnosis of GI disorders. Our study highlights the potential of curriculum self-supervised learning in utilizing unlabeled GI tract images to improve the diagnosis of GI disorders, paving the way for more accurate and efficient diagnosis in GI endoscopy.

Train the paediatric colonoscopy trainer course: Assessment of perceived value in improving colonoscopy teaching practice.

OBJECTIVES: Endoscopy teaching practice is variable, which inevitably affects the training provided. There is only one Train the Paediatric Colonoscopy Trainer (TPCT) course in the UK. Informal feedback has been positive, but its practical value has never been formally assessed. We aim to assess the practical value of the TPCT course and how attendees perceive their teaching practice compared to nonattendees. METHODS: A questionnaire based on the TPCT course learning aims and objectives was distributed to two groups of consultant paediatric gastroenterologists who teach colonoscopy in the UK; those who had attended the course (participants) and those who had not (controls). RESULTS: The 41 completed responses were received. Overall, responses indicated participants of the TPCT course rated their confidence and knowledge in teaching practices as higher than controls (4.27 vs. 3.56 p = < 0.001). There was a statistically significant difference in all areas: set (4.21 vs. 3.71 p = 0.011), dialogue (4.29 vs. 3.55 p = < 0.001) and closure (4.37 vs. 3.6 p = < 0.001) with those who attended the TPCT course giving higher ratings. There was evidence of increased understanding of key concepts such as using standardised language, conscious competence, dual task interference and performance enhancing feedback. CONCLUSION: Attending a TPCT course results in a higher perceived level of knowledge in fundamental teaching principles and confidence in colonoscopy teaching skills.

Cronkhite-Canada syndrome with esophagus involvement and six-year follow-up: A case report.

BACKGROUND: Cronkhite-Canada syndrome (CCS) is a rare, noninherited disease characterized by gastrointestinal polyposis with diarrhea and ectodermal abnormalities. CCS polyps are distributed through the whole digestive tract, and they are common in the stomach and colon but very uncommon in the esophagus. CASE SUMMARY: Here, we present a case of a 63-year-old man with skin hyperpigmentation accompanied by diarrhea, alopecia, and loss of his fingernails. Laboratory data indicated anemia, hypoalbuminemia, hypocalcemia, hypokalemia, and positive fecal occult blood. Endoscopy showed numerous polyps scattered throughout the digestive tract, including the esophagus. He was treated with nutritional support and glucocorticoids with remission of his symptoms. CONCLUSION: Comprehensive treatment led by hormonal therapy can result in partial or full remission of clinical symptoms. Treatment should be individualized for each patient according to their therapy response. Surveillance endoscopy is necessary for assessing mucosal disease activity and detecting malignant transformation.

Learning curve of achieving competency in emergency endoscopy in upper gastrointestinal bleeding: how much experience is necessary?

OBJECTIVES: The management of upper gastrointestinal bleeding (UGIB) has seen rapid advancements with revolutionising innovations. However, insufficient data exist on the necessary number of emergency endoscopies needed to achieve competency in haemostatic interventions. DESIGN: We retrospectively analysed all oesophagogastroduodenoscopies with signs of recent haemorrhage performed between 2015 and 2022 at our university hospital. A learning curve was created by plotting the number of previously performed oesophagogastroduodenoscopies with signs of recent haemorrhage against the treatment failure rate, defined as failed haemostasis, rebleeding and necessary surgical or radiological intervention. RESULTS: The study population included 787 cases with a median age of 66 years. Active bleeding was detected in 576 cases (73.2%). Treatment failure occurred in 225 (28.6%) cases. The learning curve showed a marked decline in treatment failure rates after nine oesophagogastroduodenoscopies had been performed by the respective endoscopists followed by a first plateau between 20 and 50 procedures. A second decline was observed after 51 emergency procedures followed by a second plateau. Endoscopists with experience of <10 emergency procedures had higher treatment failure rates compared with endoscopists with >51 emergency oesophagogastroduodenoscopies performed (p=0.039) or consultants (p=0.041). CONCLUSIONS: Our data suggest that a minimum number of 20 oesophagogastroduodenoscopies with signs of recent haemorrhage is necessary before endoscopists should be considered proficient to perform emergency procedures independently. Endoscopists might be considered as advanced-qualified experts in managing UGIB after a minimum of 50 haemostatic procedure performed. Implementing recommendations on minimum numbers of emergency endoscopies in education programmes of endoscopy trainees could improve their confidence and competency in managing acute UGIB.

Position statement on how can we can implement the Greendeal in our gastrointestinal and gastrointestinal endoscopy department in Belgium.

The importance to reach the target to be carbon net zero by 2050, as presented by the European Commission in the European Green Deal, cannot be overestimated. In a current endoscopy world, where single use has found its place and techniques are constantly evolving, it will be a challenge to reach these goals. How can we reconcile this evolution to a carbon neutral status by 2050 without compromising patients care, clinical standards and training needs? The European Society of Gastrointestinal Endoscopy (ESGE) together with the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) recently published a position statement (1) whereas in the UK there is the work from the green endoscopy group (2) in line with the strategy of the British Society of Gastroenterology (BSG) on sustainability (3). In Flanders, a project called "greendeal in duurzame zorg" had its kick off in March 2023 (4) so it is about time that we in Belgium, as gastroenterologists, start with tangible actions to a more sustainable daily practice. We wrote this position statement in cooperation with the Vlaamse Vereniging voor Gastro-Enterologie (VVGE), the Société royale belge de Gastro-entérologie (SRBGE) and the Belgian Society of Gastrointestinal Endoscopy (BSGIE). We will also work together in the coming years to continue to motivate our members to work on these initiatives and to co-opt new projects within the framework of the greendeal.

[Endoscopic Diagnosis and Treatment of Early Mucosal Neoplasms in the Oesophagus]. / Endoskopische Diagnostik und Therapie von malignen epithelialen Läsionen und ihren Vorläufern im Ösophagus.

Endoscopy is the gold standard for diagnosis of oesophageal cancer and its precursor lesions. Besides this, endoscopy treatment of these precursor lesions and early oesophageal cancer has been well evaluated and established. This includes dysplastic lesions associated with Barrett's oesophagus and early adenocarcinoma, as well as early squamous cell cancer of the oesophagus. The role of endoscopy for diagnosis and treatment of these lesions is summarised.

Life-threatening Gastrointestinal Bleeding from a Dieulafoy's Lesion in the Duodenum: A Case Report.

Dieulafoy's lesion is a rare cause of gastrointestinal bleeding, accounting for approximately 1-2% of all cases of gastrointestinal bleeding. Dieulafoy's lesion usually occurs in the lesser curvature of the stomach within six centimeters of the gastroesophageal junction. On the other hand, extragastric Dieulafoy's lesions are uncommon. Diagnosing an extragastric Dieulafoy's lesion by endoscopy can be challenging because of its small size and obscure location. The key elements for an accurate diagnosis include heightened awareness and a careful early endoscopic evaluation following a bleeding episode. Various endoscopic hemostatic techniques can be used for treatment. This paper presents a case of successful hemostasis using argon plasma coagulation for a life-threatening duodenal Dieulafoy's lesion.

Curative criteria for endoscopic treatment of gastric cancer.

Endoscopic treatment, particularly endoscopic submucosal dissection, has become the primary treatment for early gastric cancer. A comprehensive optical assessment, including white light endoscopy, image-enhanced endoscopy, and magnification, are the cornerstones for clinical staging and determining the resectability of lesions. This paper discusses factors that influence the indication for endoscopic resection and the likelihood of achieving a curative resection. Our review stresses the critical need for interpreting the histopathological report in accordance with clinical guidelines and the imperative of tailoring decisions based on the patients' and lesions' characteristics and preferences. Moreover, we offer guidance on managing complex scenarios, such as those involving non-curative resection. Finally, we identify future research avenues, including the role of artificial intelligence in estimating the depth of invasion and the urgent need to refine predictive scores for lymph node metastasis and metachronous lesions.