Background and aims  Capsule endoscopy (CE) has revolutionized small-bowel (SB) investigation. Computational methods can enhance diagnostic yield (DY); however, incorporating machine learning algorithms (MLAs) into CE reading is difficult as large amounts of image annotations are required for training. Current databases lack graphic annotations of pathologies and cannot be used. A novel database, KID, aims to provide a reference for research and development of medical decision support systems (MDSS) for CE. Methods  Open-source software was used for the KID database. Clinicians contribute anonymized, annotated CE images and videos. Graphic annotations are supported by an open-access annotation tool (Ratsnake). We detail an experiment based on the KID database, examining differences in SB lesion measurement between human readers and a MLA. The Jaccard Index (JI) was used to evaluate similarity between annotations by the MLA and human readers. Results  The MLA performed best in measuring lymphangiectasias with a JI of 81 ± 6 %. The other lesion types were: angioectasias (JI 64 ± 11 %), aphthae (JI 64 ± 8 %), chylous cysts (JI 70 ± 14 %), polypoid lesions (JI 75 ± 21 %), and ulcers (JI 56 ± 9 %). Conclusion  MLA can perform as well as human readers in the measurement of SB angioectasias in white light (WL). Automated lesion measurement is therefore feasible. KID is currently the only open-source CE database developed specifically to aid development of MDSS. Our experiment demonstrates this potential.

Background and study aims Nomenclature and descriptions of small bowel (SB) vascular lesions in capsule endoscopy (CE) are scarce in the medical literature. They are mostly based on the reader's opinion and thus differ between experts, with a potential negative impact on clinical care, teaching and research regarding SBCE. Our aim was to better define a nomenclature and to give a description of the most frequent vascular lesions in SBCE. Methods A panel of 18 European expert SBCE readers was formed during the UEGW 2016 meeting. Three experts constructed an Internet-based four-round Delphi consensus, but did not participate in the voting process. They built questionnaires that included various still frames of vascular lesions obtained with a third-generation SBCE system. The 15 remaining participants were asked to rate different proposals and description of the most common SB vascular lesions. A 6-point rating scale (varying from ‘strongly disagree’ to ‘strongly agree’) was used successive rounds. The consensus was reached when at least 80 % voting members scored the statement within the ‘agree’ or ‘strongly agree’. Results Consensual terms and descriptions were reached for angiectasia/angiodysplasia, erythematous patch, red spot/dot, and phlebectasia. A consensual description was reached for more subtle vascular lesions tentatively named “diminutive angiectasia” but no consensus was reached for this term. Conclusion An international group has reached a consensus on the nomenclature and descriptions of the most frequent and relevant SB vascular lesions in CE. These terms and descriptions are useful in daily practice, for teaching and for medical research purposes.

Small bowel (SB) capsule endoscopy (SBCE) is often perceived by both patients and physicians as a "lightweight," noninvasive, comfortable procedure that is easily performed with little more than swallowing a pill and a glass of water. However, "easy to carry out" does not translate to ease of reading or interpretation. A SB capsule acquires thousands of images and generates a long video; however, clinically relevant findings are often seen in only a few frames. There is no way to direct or focus the camera, the capsule's lens cannot be cleaned or luminal debris removed, and perhaps most importantly, the capsule cannot take tissue samples. Therefore, the rate of missed lesions in the SB has been quoted as high as 10 % [1]. Despite various SB imaging modalities offering similar diagnostic yield (DY) and miss rates, SBCE is one of the few endoscopic procedures open to immense scrutiny, as the data recorded are readily accessible for further on-demand review. This may expose clinicians to additional litigation but conversely, also provides a unique learning platform for new generations of SBCE readers. This is certainly fertile ground for virtual artificial neural network (ANN) training systems and even artificial intelligence (AI) diagnosis [2]. Currently, several different SBCE platforms exist. They differ in technical features and specifications such as size and weight, number and position of cameras, frame rate acquisition, and battery duration, as well as in several functions of proprietary reading software. In this editorial, we aim to provide general principles for SBCE reading, which are only partially addressed in recent technical reviews or guidelines [3-9]. We would also like to suggest tips and tricks to reduce common deficiencies in SBCE.

Background and aims: The patency capsule is designed to evaluate the patency of the small bowel before administration of small-bowel capsule endoscopy (SBCE) in patients at high risk of retention. The utilization of a patency capsule may be associated with a risk of symptomatic retention, but very few cases have been reported to date. The aim of our study was to describe our experience with this rare complication of a patency capsule. Methods: This was a multicenter retrospective case series. The medical records of patients who underwent a patency capsule test were scanned and all cases of symptomatic retention were collected. Results: In total, 20 symptomatic cases of retention out of 1615 (1.2 %) patency capsule tests were identified; in one patient, the patency capsule was retained in the esophagus, in the rest, the capsule was detected in the small bowel resulting in abdominal pain or small-bowel obstruction. One patient (5 %) required surgery; all other patients resolved spontaneously or after corticosteroid therapy. Conclusions: Symptomatic patency capsule retention is a very rare complication with a favorable prognosis. It should be recognized but its use in patients with suspected small-bowel stenosis should not be discouraged.

Capsule endoscopy (CE) emerged out of the pressing clinical need to image the small bowel (SB) in cases of midgut bleeding and provide an overall comfortable and reliable gastrointestinal (GI) diagnosis 1. Since its wider adoption in clinical practice, significant progress has been made in several areas including software development, hardware features and clinical indications, while innovative applications of CE never cease to appear 2 3. Currently, several manufacturers provide endoscopic capsules with more or less similar technological features 4. Although there is engaging and continuous academic and industry-fueled R&D, promising furtherment of CE technology 4 5, the current status of clinical CE remains that of by and large an imaging modality. Clinical relevance of CE images is cornerstone in the decision-making process for medical management. In one of the larger to date SB CE studies, 4,206 abnormal images were detected in 3,280 patients 6. Thus, CE leads to the identification of a large amount of potential pathology, some of which are pertinent (or relevant) while some (probably the majority) are not.Soon artificial intelligence (AI) is likely to carry out several roles currently performed by humans; in fact, we are witnessing only the first stages of a transition in the clinical adoption of AI-based solutions in several aspects of gastroenterology including CE 7. Until then though, human-based decision-making profoundly impacts patient care and – although not suggested in the updated European Society of Gastrointestinal Endoscopy (ESGE) European curriculum 8 9 – it should be an integral part of CE training. Frequently, interpretation of CE images by experts or at least experienced readers differs. In a tandem CE reading study, expert review of discordant cases revealed a 50 % (13/25 discordant results) error rate by experienced readers, corresponding (in 5/13 cases) to ‘over-classification’ of an irrelevant abnormality 10. Another comparative study showed an ‘over-classification’ of such irrelevant abnormalities in ~10 % of CE readings 11. One thing which has been for a while on the table – in relation to optimizing and/or standardizing CE reporting and subsequent decision-making – is the need for reproducible scoring systems and for a reliable common language among clinicians responsible for further patient’s management.Over the years, several of these scoring systems were developed while others appear in the wake of software and hardware improvements aiming to replace and/or complement their predecessors. This review presents a comprehensive account of the currently available classification/scoring systems in clinical CE spanning from predicting the bleeding potential of identified SB lesions (with emphasis on vascular lesions), and the individual rebleeding risk; scoring systems for the prediction of SB lesions in patients with obscure gastrointestinal bleeding (OGlB), having the potential to improve patient selection and rationalize the use of enteroscopy, with better allocation of resources, optimized diagnostic workflow and tailored treatment. This review also includes scores for reporting the inflammatory burden, the cleansing level that underscores confidence in CE reporting and the mass or bulge question in CE. Essentially, the aim is to become a main text for reference when scoring is required and facilitate the inclusion of -through readiness of access- one of the other in the final report.