AI-assisted capsule endoscopy reading in suspected small bowel bleeding: a multicentre prospective study.

BACKGROUND: Capsule endoscopy reading is time consuming, and readers are required to maintain attention so as not to miss significant findings. Deep convolutional neural networks can recognise relevant findings, possibly exceeding human performances and reducing the reading time of capsule endoscopy. Our primary aim was to assess the non-inferiority of artificial intelligence (AI)-assisted reading versus standard reading for potentially small bowel bleeding lesions (high P2, moderate P1; Saurin classification) at per-patient analysis. The mean reading time in both reading modalities was evaluated among the secondary endpoints. METHODS: Patients aged 18 years or older with suspected small bowel bleeding (with anaemia with or without melena or haematochezia, and negative bidirectional endoscopy) were prospectively enrolled at 14 European centres. Patients underwent small bowel capsule endoscopy with the Navicam SB system (Ankon, China), which is provided with a deep neural network-based AI system (ProScan) for automatic detection of lesions. Initial reading was performed in standard reading mode. Second blinded reading was performed with AI assistance (the AI operated a first-automated reading, and only AI-selected images were assessed by human readers). The primary endpoint was to assess the non-inferiority of AI-assisted reading versus standard reading in the detection (diagnostic yield) of potentially small bowel bleeding P1 and P2 lesions in a per-patient analysis. This study is registered with ClinicalTrials.gov, NCT04821349. FINDINGS: From Feb 17, 2021 to Dec 29, 2021, 137 patients were prospectively enrolled. 133 patients were included in the final analysis (73 [55%] female, mean age 66·5 years [SD 14·4]; 112 [84%] completed capsule endoscopy). At per-patient analysis, the diagnostic yield of P1 and P2 lesions in AI-assisted reading (98 [73·7%] of 133 lesions) was non-inferior (p<0·0001) and superior (p=0·0213) to standard reading (82 [62·4%] of 133; 95% CI 3·6-19·0). Mean small bowel reading time was 33·7 min (SD 22·9) in standard reading and 3·8 min (3·3) in AI-assisted reading (p<0·0001). INTERPRETATION: AI-assisted reading might provide more accurate and faster detection of clinically relevant small bowel bleeding lesions than standard reading. FUNDING: ANKON Technologies, China and AnX Robotica, USA provided the NaviCam SB system.

Updates in the diagnosis and management of small-bowel tumors.

Small-bowel tumors represent a rare entity comprising 0.6% of all new cancer cases in the US, and only 3% of all gastrointestinal neoplasms. They are a heterogenous group of neoplasms comprising of about forty different histological subtypes with the most common being adenocarcinoma, neuroendocrine tumors, stromal tumors and lymphomas. Their incidence has been reportedly increasing over recent years, partly owing to the advances and developments in the diagnostic modalities. Small-bowel capsule endoscopy, device assisted enteroscopy and dedicated small-bowel cross-sectional imaging are complimentary tools, supplementing each other in the diagnostic process. Therapeutic management of small-bowel tumors largely depends on the histological type and staging at diagnosis. The aim of the present review article is to discuss relevant advances in the diagnosis and management of small-bowel tumors.

Where does capsule endoscopy fit in the diagnostic algorithm of small bowel intussusception?

INTRODUCTION: The investigation of small bowel (SB) intussusception is variable, reflecting the lack of existing standards. The aim of this study was to understand the role of small bowel capsule endoscopy (SBCE) to investigate this pathology. METHODOLOGY: This was a retrospective multi-centre study. Patients with intussusception on SBCE and those where SBCE was carried out due to findings of intussusception on radiological investigations were included. Relevant information was collected. RESULTS: Ninety-five patients (median age 39+/-SD19.1 years, IQR 30) were included. Radiological investigations were carried out in 71 patients (74.7%) prior to SBCE with intussusception being present in 60 patients on radiological investigations (84.5%). Thirty patients (42.2%) had intussusception on radiological investigations followed by a normal SBCE. Ten patients (14.1%) had findings of intussusception on radiological investigations, a normal SBCE and repeat radiological investigations that were also normal. Abnormal findings were noted on SBCE that could explain intussusception on imaging in (16 patients) 22.5% of patients. Five patients (5.3%) underwent radiological investigations and SBCE to investigate coeliac disease and intussusception. None had associated malignancy. Four patients (4.2%) underwent SBCE to investigate familial polyposis syndromes and went on to SB enteroscopy and surgery accordingly. Most patients (n = 14; 14.8%) with intussusception on initial SBCE (without prior radiological imaging) had suspected SB bleeding (n = 10, 10.5%). Four patients (4.2%) had additional findings of a mass on CT scan and went on to have surgery. CONCLUSION: SBCE should be used to complement radiology when investigating intussusception. It is a safe non-invasive test that will minimise unnecessary surgery. Additional radiological investigations following a negative SBCE in cases of intussusception noted on initial radiological investigations are unlikely to yield positive findings. Radiological investigations following intussusception noted on SBCE in case of patients presenting with obscure gastrointestinal bleeding, may yield additional findings.

Small-bowel capsule endoscopy in patients with Meckel's diverticulum: clinical features, diagnostic workup, and findings. A European multicenter I-CARE study.

BACKGROUND AND AIMS: Meckel's diverticulum (MD) may remain silent or be associated with adverse events such as GI bleeding. The main aim of this study was to evaluate indicative small-bowel capsule endoscopy (SBCE) findings, and the secondary aim was to describe clinical presentation in patients with MD. METHODS: This retrospective European multicenter study included patients with MD undergoing SBCE from 2001 until July 2021. RESULTS: Sixty-nine patients with a confirmed MD were included. Median age was 32 years with a male-to-female ratio of approximately 3:1. GI bleeding or iron-deficiency anemia was present in nearly all patients. Mean hemoglobin was 7.63 ± 1.8 g/dL with a transfusion requirement of 52.2%. Typical capsule endoscopy (CE) findings were double lumen (n = 49 [71%]), visible entrance into the MD (n = 49 [71%]), mucosal webs (n = 30 [43.5%]), and bulges (n = 19 [27.5%]). Two or more of these findings were seen in 48 patients (69.6%). Ulcers were detected in 52.2% of patients (n = 36). In 63.8% of patients (n = 44), a combination of double lumen and visible entrance into the MD was evident, additionally revealing ulcers in 39.1% (n = 27). Mean percent SB (small bowel) transit time for the first indicative image of MD was 57% of the total SB transit time. CONCLUSIONS: Diagnosis of MD is rare and sometimes challenging, and a preoperative criterion standard does not exist. In SBCE, the most frequent findings were double-lumen sign and visible diverticular entrance, sometimes together with ulcers.

Small-bowel capsule endoscopy and device-assisted enteroscopy for diagnosis and treatment of small-bowel disorders: European Society of Gastrointestinal Endoscopy (ESGE) Guideline - Update 2022.

MR1: ESGE recommends small-bowel capsule endoscopy as the first-line examination, before consideration of other endoscopic and radiological diagnostic tests for suspected small-bowel bleeding, given the excellent safety profile of capsule endoscopy, its patient tolerability, and its potential to visualize the entire small-bowel mucosa.Strong recommendation, moderate quality evidence. MR2: ESGE recommends small-bowel capsule endoscopy in patients with overt suspected small-bowel bleeding as soon as possible after the bleeding episode, ideally within 48 hours, to maximize the diagnostic and subsequent therapeutic yield.Strong recommendation, high quality evidence. MR3: ESGE does not recommend routine second-look endoscopy prior to small-bowel capsule endoscopy in patients with suspected small-bowel bleeding or iron-deficiency anemia.Strong recommendation, low quality evidence. MR4: ESGE recommends conservative management in those patients with suspected small-bowel bleeding and high quality negative small-bowel capsule endoscopy.Strong recommendation, moderate quality evidence. MR5: ESGE recommends device-assisted enteroscopy to confirm and possibly treat lesions identified by small-bowel capsule endoscopy.Strong recommendation, high quality evidence. MR6: ESGE recommends the performance of small-bowel capsule endoscopy as a first-line examination in patients with iron-deficiency anemia when small bowel evaluation is indicated.Strong recommendation, high quality evidence. MR7: ESGE recommends small-bowel capsule endoscopy in patients with suspected Crohn's disease and negative ileocolonoscopy findings as the initial diagnostic modality for investigating the small bowel, in the absence of obstructive symptoms or known bowel stenosis.Strong recommendation, high quality evidence. MR8: ESGE recommends, in patients with unremarkable or nondiagnostic findings from dedicated small-bowel cross-sectional imaging, small-bowel capsule endoscopy as a subsequent investigation if deemed likely to influence patient management.Strong recommendation, low quality evidence. MR9: ESGE recommends, in patients with established Crohn's disease, the use of a patency capsule before small-bowel capsule endoscopy to decrease the capsule retention rate.Strong recommendation, moderate quality evidence. MR10: ESGE recommends device-assisted enteroscopy (DAE) as an alternative to surgery for foreign bodies retained in the small bowel requiring retrieval in patients without acute intestinal obstruction.Strong recommendation, moderate quality evidence. MR11: ESGE recommends DAE-endoscopic retrograde cholangiopancreatography (DAE-ERCP) as a first-line endoscopic approach to treat pancreaticobiliary diseases in patients with surgically altered anatomy (except for Billroth II patients).Strong recommendation, moderate quality evidence.

Key research questions for implementation of artificial intelligence in capsule endoscopy.

Background: Artificial intelligence (AI) is rapidly infiltrating multiple areas in medicine, with gastrointestinal endoscopy paving the way in both research and clinical applications. Multiple challenges associated with the incorporation of AI in endoscopy are being addressed in recent consensus documents. Objectives: In the current paper, we aimed to map future challenges and areas of research for the incorporation of AI in capsule endoscopy (CE) practice. Design: Modified three-round Delphi consensus online survey. Methods: The study design was based on a modified three-round Delphi consensus online survey distributed to a group of CE and AI experts. Round one aimed to map out key research statements and challenges for the implementation of AI in CE. All queries addressing the same questions were merged into a single issue. The second round aimed to rank all generated questions during round one and to identify the top-ranked statements with the highest total score. Finally, the third round aimed to redistribute and rescore the top-ranked statements. Results: Twenty-one (16 gastroenterologists and 5 data scientists) experts participated in the survey. In the first round, 48 statements divided into seven themes were generated. After scoring all statements and rescoring the top 12, the question of AI use for identification and grading of small bowel pathologies was scored the highest (mean score 9.15), correlation of AI and human expert reading-second (9.05), and real-life feasibility-third (9.0). Conclusion: In summary, our current study points out a roadmap for future challenges and research areas on our way to fully incorporating AI in CE reading.

Score reproducibility and reliability in differentiating small bowel subepithelial masses from innocent bulges.

AIMS: The primary aim of this study was to assess the reliability, intra- and inter-observer variation of the SPICE, Mucosal protrusion angle (MPA) and SHYUNG scores in differentiating a subepithelial mass (SEM) from a bulge. METHODS: This retrospective multicentre study analysed the 3 scores, radiological studies, enteroscopy and/or surgical findings. RESULTS: 100 patients with a potential SEM (mean age 57.6years) were recruited with 75 patients having pathology. In patients with a SEM the mean SPICE score was 2.04 (95% CI 1.82-2.26) as compared to 1.16 (95% CI 0.81-1.51) without any pathology (AUC 0.74, p<0.001), with a fair intra-observer agreement (Kappa 0.3, p<0.001) and slight inter-observer agreement (Kappa 0.14, p<0.05). SPICE had a 37.3% sensitivity and 92.0% specificity in distinguishing between a SEM and bulge, whereas MPA<90˚ had 58.7% and 76.0% respectively, with poor intra-observer(p = 0.05) and interobserver agreement (p = 0.64). The SHYUNG demonstrated a moderate intra-observer (Kappa 0.44, p<0.001) and slight inter-observer reliability (Kappa 0.18, p<0.001). The sensitivity of an elevated SHYUNG score (≥4) in identifying a SEM was 18.7% with a specificity of 92.0% (AUC 0.71, p = 0.002). CONCLUSIONS: Though these scores are easy to use, they have, at best, slight to moderate intra and inter-observer agreement. Their overall diagnostic performances are limited.

Performance measures for colonoscopy in inflammatory bowel disease patients: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative.

The European Society of Gastrointestinal Endoscopy (ESGE) presents a short list of performance measures for colonoscopy in inflammatory bowel disease (IBD) patients. Current performance measures for colonoscopy mainly focus on detecting (pre)malignant lesions. However, these performance measures are not relevant for all colonoscopy indications in IBD patients. Therefore, our aim was to provide endoscopy services across Europe and other interested countries with a tool for quality monitoring and improvement in IBD colonoscopy. Eight key performance measures and one minor performance measure were recommended for measurement and evaluation in daily endoscopy practice.

Nomenclature and Definition of Atrophic Lesions in Small Bowel Capsule Endoscopy: A Delphi Consensus Statement of the International CApsule endoscopy REsearch (I-CARE) Group.

(1) Background: Villous atrophy is an indication for small bowel capsule endoscopy (SBCE). However, SBCE findings are not described uniformly and atrophic features are sometimes not recognized; (2) Methods: The Delphi technique was employed to reach agreement among a panel of SBCE experts. The nomenclature and definitions of SBCE lesions suggesting the presence of atrophy were decided in a core group of 10 experts. Four images of each lesion were chosen from a large SBCE database and agreement on the correspondence between the picture and the definition was evaluated using the Delphi method in a broadened group of 36 experts. All images corresponded to histologically proven mucosal atrophy; (3) Results: Four types of atrophic lesions were identified: mosaicism, scalloping, folds reduction, and granular mucosa. The core group succeeded in reaching agreement on the nomenclature and the descriptions of these items. Consensus in matching the agreed definitions for the proposed set of images was met for mosaicism (88.9% in the first round), scalloping (97.2% in the first round), and folds reduction (94.4% in the first round), but granular mucosa failed to achieve consensus (75.0% in the third round); (4) Conclusions: Consensus among SBCE experts on atrophic lesions was met for the first time. Mosaicism, scalloping, and folds reduction are the most reliable signs, while the description of granular mucosa remains uncertain.

Performance measures for the SACRED team-centered approach to advanced gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy (ESGE) Quality Improvement Initiative.

The European Society of Gastrointestinal Endoscopy and United European Gastroenterology have defined performance measures for upper and lower gastrointestinal, pancreaticobiliary, and small-bowel endoscopy. Quality indicators to guide endoscopists in the growing field of advanced endoscopy are also underway. We propose that equal attention is given to developing the entire advanced endoscopy team and not the individual endoscopist alone.We suggest that the practice of teams intending to deliver high quality advanced endoscopy is underpinned by six crucial principles concerning: selection, acceptance, complications, reconnaissance, envelopment, and documentation (SACRED).

Lavage, Simethicone, and Prokinetics-What to Swallow with a Video Capsule.

The development of new capsules now allows endoscopic diagnosis in all segments of the gastrointestinal tract and comes with new needs for differentiated preparation regimens. Although the literature is steadily increasing, the results of the conducted trials on preparation are sometimes conflicting. The ingestion of simethicone before gastric and small bowel capsule endoscopy for prevention of air bubbles is established. The value of a lavage before small bowel capsule endoscopy (SBCE) is recommended, although not supported by all studies. Ingestion in the morning before the procedure seems useful for the improvement of mucosa visualization. Lavage after swallowing of the capsule seems to improve image quality, and in some studies also diagnostic yield. Prokinetics has been used with first generation capsules to shorten gastric transit time and increase the rate of complete small bowel visualization. With the massively prolonged battery capacity of the new generation small bowel capsules, prokinetics are only necessary in significantly delayed gastric emptying as documented by a real-time viewer. Lavage is crucial for an effective colon capsule or pan-intestinal capsule endoscopy. Mainly high or low volume polyethylene glycol (PEG) is used. Apart from achieving optimal cleanliness, propulsion of the capsule by ingested boosts is required to obtain a complete passage through the colon within the battery lifetime. Boosts with low volume sodium picosulfate (NaP) or diatrizoate (gastrografin) seem most effective, but potentially have more side effects than PEG. Future research is needed for more patient friendly but effective preparations, especially for colon capsule and pan-intestinal capsule endoscopy.

Implementation of European Society of Gastrointestinal Endoscopy (ESGE) recommendations for small-bowel capsule endoscopy into clinical practice: Results of an official ESGE survey.

BACKGROUND: We aimed to document international practices in small-bowel capsule endoscopy (SBCE), measuring adherence to European Society of Gastrointestinal Endoscopy (ESGE) technical and clinical recommendations. METHODS: Participants reached through the ESGE contact list completed a 52-item web-based survey. RESULTS: 217 responded from 47 countries (176 and 41, respectively, from countries with or without a national society affiliated to ESGE). Of respondents, 45 % had undergone formal SBCE training. Among SBCE procedures, 91 % were performed with an ESGE recommended indication, obscure gastrointestinal bleeding (OGIB), iron-deficiency anemia (IDA), and suspected/established Crohn's disease being the commonest and with higher rates of positive findings (49.4 %, 38.2 % and 53.5 %, respectively). A watchful waiting strategy after a negative SBCE for OGIB or IDA was preferred by 46.7 % and 70.3 %, respectively. SBCE was a second-line exam for evaluation of extent of new Crohn's disease for 62.2 % of respondents. Endoscopists adhered to varying extents to ESGE technical recommendations regarding bowel preparation ( > 60 %), use in those with pacemaker holders (62.5 %), patency capsule use (51.2 %), and use of a validated scale for bowel preparation assessment (13.3 %). Of the respondents, 67 % read and interpreted the exams themselves and 84 % classified exams findings as relevant or irrelevant. Two thirds anticipated future increase in SBCE demand. Inability to obtain tissue (78.3 %) and high cost (68.1 %) were regarded as the main limitations, and implementation of artificial intelligence as the top development priority (56.2 %). CONCLUSIONS: To some extent, endoscopists follow ESGE guidelines on using SBCE in clinical practice. However, variations in practice have been identified, whose implications require further evaluation.

Erratum: Scoring systems in clinical small-bowel capsule endoscopy: all you need to know!

[This corrects the article DOI: 10.1055/a-1372-4051.].

How should we do colon capsule endoscopy reading: a practical guide.

In this article, we aim to provide general principles as well as personal views for colonic capsule endoscopy. To allow an in-depth understanding of the recommendations, we also present basic technological characteristics and specifications, with emphasis on the current as well as the previous version of colonic capsule endoscopy and relevant software. To date, there is no scientific proof to support the optimal way of reading a colonic capsule endoscopy video, or any standards or guidelines exist. Hence, any advice is a mixture of recommendations by the capsule manufacturer and experts' opinion. Furthermore, there is a paucity of data regarding the use of term(s) (pre-reader/reader-validator) in colonic capsule endoscopy. We also include a couple of handy tables in order to get info at a glance.

Feasibility and diagnostic yield of small-bowel capsule endoscopy in patients with surgically altered gastric anatomy: the SAGA study.

BACKGROUND AND AIMS: Little is known about small-bowel (SB) capsule endoscopy (CE) in patients with a history of gastric surgery. This study aims to evaluate the feasibility and diagnostic yield (DY) of orally ingested SB-CE in patients with surgically altered gastric anatomy. METHODS: Twenty-four European centers retrospectively identified patients who had SB-CE after total or subtotal gastrectomy. The primary outcome was the DY of SB-CE (intermediate P1 to highly P2 relevant findings). Secondary outcomes were gastric and SB transit times, completion, cleanliness, and adverse event rates. RESULTS: Studied were 248 procedures from 243 patients (mean age, 62 years) with a history of partial gastrectomy (Billroth I, 13.1%; Billroth II, 34.6%), total gastrectomy (7.4%), Whipple procedure (12.8%), sleeve gastrectomy (7.2%), or gastric bypass surgery (24.7%). Obscure GI bleeding was the most frequent indication (85.1%). SB completion rate was 84.3%. One capsule retention in the SB was noted (adverse event rate, .4%). Median SB transit time was 286 minutes (interquartile range [235; 387]). Cleanliness was rated as adequate in 92.1% of procedures. After exclusion of abnormalities found at the upper anastomotic site, the DY was 43.6%, with inflammatory/ulcerated lesions observed more frequently (23.4%) than vascular lesions (21.0%). CONCLUSIONS: SB-CE seems to be feasible and safe in selected patients with a history of major gastric surgery and comes with a high DY. The spectrum of abnormal SB findings in these patients may be different from what is known from the literature in nonoperated patients.

Infectious diseases affecting the small bowel - what not to miss.

PURPOSE OF REVIEW: This review summarizes infectious diseases involving the small bowel (SB) with a focus on recent literature related to diagnosis and pathophysiology. RECENT FINDINGS: Typical symptom for SB infections is diarrhea, mostly self-limiting. Pathogens include bacteria, viruses, fungi, protozoan parasites, and helminths. Host-pathogen interaction is of special interest in infections with potentially severe or prolonged course. Research uses increasingly enterocyte cell culture systems. SARS-CoV2 can also infect enterocytes via angiotensin converting enzyme 2 (ACE2) receptor and causes gastrointestinal complaints in some patients. Chronic SB infections as tuberculosis, Cytomegalovirus, or Epstein-Barr virus have to be differentiated from Crohn's and other diseases. Severe rare fungal and protozoan parasitic infections can cause relevant morbidity in immunocompromised patients. Soil-transmitted helminthic infections are a special issue in endemic areas. SUMMARY: Many infections involve the SB, typically causing mild and self-limiting diarrhea. Symptomatic therapy, hygiene, and isolation are the mainstay of management. However, some patients develop severe or chronic disease. Immunosuppression is a major cause for severe, but also for rare opportunistic systemic infections that can also affect the SB.

Curriculum for small-bowel capsule endoscopy and device-assisted enteroscopy training in Europe: European Society of Gastrointestinal Endoscopy (ESGE) Position Statement.

The European Society of Gastrointestinal Endoscopy (ESGE) has recognized the need to formalize training in small-bowel endoscopy across European centers. The following criteria and framework for training in small-bowel capsule endoscopy (SBCE) and device-assisted enteroscopy (DAE), which aim to provide uniform and high quality training to ensure that small-bowel endoscopists are competent to operate independently, are based on the current literature and experience of experts in the field. Three main areas are covered: skills required prior to commencing training in small-bowel endoscopy; structured training for trainees to become independent endoscopists; and ways of ensuring competence is achieved. 1 : Centers providing training in SBCE should perform a minimum of 75 - 100 SBCEs/year. 2 : Experience in bidirectional endoscopies is desirable for structured training in SBCE. 3 : SBCE courses should consist of at least 50 % hands-on training and cover information on technology, indications and contraindications for SBCE, pathologies that can be encountered on SBCE, and standard terminology that should be used during reporting of SBCE. An SBCE course should be completed prior to achieving competence in SBCE reporting. 4 : Competence in SBCE can be assessed by considering a minimum of 30 SBCEs. Direct Observation of Procedural Skills, short SBCE videos, and multiple-choice questions can be useful to assess improvement in the skills of trainees. 5 : Centers offering training in DAE should aim to carry out at least 75 DAEs/year, should have direct links with an SBCE service, and should allow regular discussion of cases at a radiology small-bowel MDT. Training centers with lower numbers are encouraged to offer training by "buddying-up" with other centers, or using mentoring systems. 6 : DAE trainees must be independent in bidirectional endoscopies and have experience in level 1 polypectomy prior to commencement of training. They should also be competent in reviewing SBCEs. 7 : Training in DAE should be structured with a minimum of 75 procedures, including 35 retrograde DAEs, with therapeutic procedures undertaken in at least 50 % of the DAEs performed. Training should cover the indications, contraindications, complications including prevention, and technicalities of the DAE procedure; formal evaluation should follow. DAE trainees must acquire skills to independently manage and advise on small-bowel pathology following DAE procedures. 8 : It is highly recommended that international societies develop online modules and courses on DAE, which are currently lacking across Europe.

Nomenclature and semantic descriptions of ulcerative and inflammatory lesions seen in Crohn's disease in small bowel capsule endoscopy: An international Delphi consensus statement.

BACKGROUND: In the medical literature, the nomenclature and descriptions (ND) of small bowel (SB) ulcerative and inflammatory (U-I) lesions in capsule endoscopy (CE) are scarce and inconsistent. Inter-observer variability in interpreting these findings remains a major limitation in the assessment of the severity of mucosal lesions, which can impact negatively on clinical care, training and research on SB-CE. OBJECTIVE: Focusing on SB-CE in Crohn's disease (CD), our aim is to establish a consensus on the ND of U-I lesions. METHODS: An international panel of experienced SB-CE readers was formed during the 2016 United European Gastroenterology Week meeting. A core group of five CE and inflammatory bowel disease (IBD) experts established an Internet-based, three-round Delphi consensus but did not participate in the voting process. The core group built illustrated questionnaires, including SB-CE still frames of U-I lesions from patients with documented CD. Twenty-seven other experts were asked to rate and comment on the different proposals for the ND of the most frequent SB U-I lesions. For each round, we used a 6-point rating scale (varying from 'strongly disagree' to 'strongly agree'). The consensus was reached when at least 80 % of the voting members scored the statement within the 'agree' or 'strongly agree' categories. RESULTS: A 100% participation rate was obtained for all the rounds. Consensual ND were reached for the following seven U-I lesions: aphthoid erosion, deep ulceration, superficial ulceration, stenosis, edema, hyperemia and denudation. CONCLUSION: Considering the most frequent SB U-I lesions seen in CE in CD, a consensual ND was reached by the international group of experts. These descriptions and names are useful not only for daily practice and medical education, but also for medical research.