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Wireless capsule endoscopy (WCE) is more and more popular in noninvasive detection on gastrointestinal (GI) disease. But the power supply is still a bottleneck. Insufficient power reduces image resolution and frame rate of data transfer, thus, unreliable medical diagnosis. Wireless power transmission (WPT) technology enables power supply for WCE. A hollow receiving coil (RC) with novel structure is proposed to minimize the capsule scale and solve the power issue. Single turn element analysis (STEA) is adopted to directly evaluate receiving power. Receiving power varies greatly when WCE is in different position and orientation of GI tract during the detection process. In some particular misalignment, power drops too low or jumps frequently. Then, optimization design of RC aimed at sufficient and stable power supply is implemented. The STEA is validated on test bench. The error of electromagnetic force is 0.2 V. The least receiving power with the optimal RC is 438.1 mW even in the worst misalignment. In the great majority of position and orientation misalignments, the optimal RC receives power over 650 mW. With the advantage of both computational time and accuracy, STEA is applicable for measurement and analysis on power for biomedical devices utilizing WPT technology, not merely WCE. In vivo experiment in pig's GI is accomplished with the optimal RC. The size of WCE with the novel RC gets smaller. And image stream is clear and fluent, when WCE is in any possible position and orientation of the tract. Four frames are stochastically sampled, in entropy of 7.1148, 7.3070, 7.2041, and 7.2570. Sufficient and stable power supply with the hollow RC enables advanced functions like drug release to come into being in WCE.

Understanding deep learning in capsule endoscopy: Can artificial intelligence enhance clinical practice?

Background and aims Capsule endoscopy (CE) is a visual modality; hence, diagnosis relies on image quality. We studied the contribution of image parameters to visualization quality and their effect on diagnostic certainty of small bowel (SB) lesions. Methods Five clear CE images of common SB pathology - two vascular lesions, two inflammatory, one polyp - were processed for three image parameters to simulate poor SB conditions: opacity (color-matched to luminal content; 10-90%, 10% increments); blurriness (radius 1-10 pixels; one pixel increments); and contrast (-50-50%; 10% increments). Nine expert readers evaluated whether images were adequate for diagnosis. Points where perception of image quality changed significantly were determined for each parameter. Three further sets of SBCE images (vascular, inflammatory, and neoplastic lesions; nine images/set) were processed for four points/parameters. Twenty experienced/expert CE readers reviewed these images. Results The negative effects of opacity in diagnostic certainty were mostly evident in images of neoplasia; images of vascular and inflammatory lesions were less affected. Similar results were observed with increasing blur radius, simulating movement, and poor focus. The proportions of readers finding vascular and inflammatory images adequate for diagnosis did not drop significantly at wider blur radii, while images of neoplasia were quickly deemed inadequate. Low contrast had a greater negative effect than high, most consistently in neoplastic lesions. Conclusion Poor visualization quality in all parameters affected mostly neoplastic lesions. Software to increase contrast and sharpen images can improve visualization quality; smart frame rate adaptation could improve the number of high-quality frames obtained. Thoroughness in SB cleansing is most important when there is a suspicion of neoplasia.

BACKGROUND AND AIM There is a lack of uniformity of reporting on features of celiac disease (CD) on small bowel capsule endoscopy (SBCE). This makes determining extent of disease and comparison of severity of disease challenging. METHODS De-identified SBCEs of 300 patients (78 CD [26%], 18 serology negative villous atrophy [6%], and 204 controls with normal duodenal histology [68%]) were included. Videos were reviewed by two experts. All patients had duodenal histology taken within 2 weeks of SBCE. The degree of agreement in CD features and extent of disease was then determined. The resulting score for each factor was used to determine overall severity of disease. RESULTS There was substantial agreement in the kappa coefficient for the detection of CD features between reviewers (0.67). Agreement for extent of affected small bowel (SB) mucosa was high (0.97). On multiple regression analysis, several features of CD correlated with extent of affected SB mucosa for both reviewers. The odds ratios derived from this analysis were then used to score features of CD, enabling scores of severity to be calculated for each patient. The median overall scores for patients increased significantly according to the independent classification of severity by the capsule reviewers: mild (20, 0-79), moderate (45, 25-123), and severe (89, 65-130) (P = 0.0001). CONCLUSION The good correlation of CD scores between expert reviewers confirms the validity of features of CD on SBCE. An objective score of CD features in the SB is useful in the follow up of patients with CD and serology negative villous atrophy.

BACKGROUND AND AIMS Terminal ileitis is a common condition and may be associated with a wide variety of diseases, mostly Crohn's disease. Although small bowel capsule endoscopy (SBCE) is a valuable diagnostic tool for small-bowel diseases, data regarding its diagnostic impact on isolated terminal ileitis are sparse. The aim of this study was to evaluate the diagnostic value of SBCE for isolated terminal ileitis detected during ileocolonoscopy and to assess predictive factors for Crohn's disease diagnosis. METHODS This is a retrospective study including consecutive patients undergoing SBCE after diagnosis of terminal ileitis without colonic mucosal abnormalities on ileocolonoscopy between January 2016 and September 2019. RESULTS This included 102 patients with isolated terminal ileitis on ileocolonoscopy. Positive findings on SBCE were found in 82.4% of patients. After performing SBCE, 61.8% of patients had a final diagnosis, being Crohn's disease the most common (34.3%), followed by NSAIDs enteropathy (12.7%). Extraintestinal manifestations (P = 0.003), weight loss (P = 0.02), abnormal imaging (P = 0.04) and positive SBCE findings (P = 0.001) were independently associated with Crohn's disease diagnosis. Regarding SBCE, presence of proximal small-bowel disease (P = 0.02), diffuse findings (P = 0.002) and moderate to severe inflammatory activity (Lewis score ≥ 790) (P < 0.001) were independently associated with Crohn's disease diagnosis. CONCLUSION SBCE is a valuable tool that should be systematically used in patients with isolated terminal ileitis on ileocolonoscopy, since it revealed a high diagnostic yield, supporting a definite diagnosis in almost two-thirds of patients, and Crohn's disease diagnosis in approximately one-third of patients. A diagnosis of Crohn's disease should be considered when a patient with terminal ileitis on ileocolonoscopy shows proximal involvement, diffuse findings and/or moderate to severe inflammatory activity on SBCE.

Background Colon capsule endoscopy (CCE) and CT colonography (CTC) are minimally invasive techniques for colorectal cancer (CRC) screening. Our objective is to compare CCE and CTC for the identification of patients with colorectal neoplasia among participants in a CRC screening programme with positive faecal immunochemical test (FIT). Primary outcome was to compare the performance of CCE and CTC in detecting patients with neoplastic lesions. Methods The VICOCA study is a prospective, single-centre, randomised trial conducted from March 2014 to May 2016; 662 individuals were invited and 349 were randomised to CCE or CTC before colonoscopy. Endoscopists were blinded to the results of CCE and CTC. Results Three hundred forty-nine individuals were included: 173 in the CCE group and 176 in the CTC group. Two hundred ninety individuals agreed to participate: 147 in the CCE group and 143 in the CTC group. In the intention-to-screen analysis, sensitivity, specificity and positive and negative predictive values for the identification of individuals with colorectal neoplasia were 98.1%, 76.6%, 93.7% and 92.0% in the CCE group and 64.9%, 95.7%, 96.8% and 57.7% in the CTC group. In terms of detecting significant neoplastic lesions, the sensitivity of CCE and CTC was 96.1% and 79.3%, respectively. Detection rate for advanced colorectal neoplasm was higher in the CCE group than in the CTC group (100% and 93.1%, respectively; RR = 1.07; p = 0.08). Both CCE and CTC identified all patients with cancer. CCE detected more patients with any lesion than CTC (98.6% and 81.0%, respectively; RR = 1.22; p = 0.002). Conclusion Although both techniques seem to be similar in detecting patients with advanced colorectal neoplasms, CCE is more sensitive for the detection of any neoplastic lesion. Trial registration ClinicalTrials.gov Identifier: NCT02081742. Registered: September 16, 2013.

In this paper, the impact of interference due to the geomagnetic field on a static magnetic localization setup for capsule endoscopy, which is suitable for a wearable application, was investigated. For this purpose, a study was carried out in which the average abdomen size of 15 subjects was evaluated. With the determined geometry values, a setup consisting of three elliptical sensor rings was modeled. Simulations were performed, where the magnetic flux density was evaluated at the sensors by using different-sized magnets. The measured values were compared with each other and the geomagnetic flux density. The results revealed that the measured values were for all evaluated magnet sizes of the order of the geomagnetic flux density, which is problematic since the calibration of sensors is no longer valid if the orientation of the wearable sensor array is changed. However, it is suggested that a differential measurement is suitable for the proposed system and could reduce static interference caused by the geomagnetic field.

Objectives This study aimed to assess the impact of polyethylene glycol (PEG) bowel cleansing on performance characteristics of small bowel capsule endoscopy (SBCE). Materials and Methods Data from consecutive patients undergoing SBCE in the period before and after the introduction of PEG 2 L bowel cleansing with PEG were collated retrospectively. The indication, diagnostic yield (DY), clinical outcome, small bowel transit time, gastric transit time, and completion rate were recorded for each procedure. Results Data from 286 patients were analyzed. PEG 2 L was not superior to 12-hour fasting for DY (66 [53%] vs. 76 [47%] patients [p = 0.348]), or DY for significant findings (findings requiring a further intervention or investigation; 29 [23%] vs. 52 [32%] patients [p = 0.090]).There was a trend toward an increased DY for significant findings in patients undergoing investigation for iron-deficiency anemia (IDA) receiving PEG 2 L that just failed to meet statistical significance (13 [31%] and 25 [21%] patients, respectively [p = 0.06]). Transit times and completion rates were unaffected by bowel cleansing. Conclusion Bowel cleansing with PEG 2 L is not superior to fasting for overall DY in SBCE. PEG 2 L may confer an advantage for the detection of significant lesions in patient with IDA. Further investigation of optimal modes of bowel preparation is indicated.

Background and Aim. Direct oral anticoagulant- (DOAC-) induced small-bowel lesions have not been described. We evaluated small-bowel lesions related to DOAC using video capsule endoscopy (VCE). Methods. This study was a prospective, open-label, nonblinded, multicenter, and observational study. From September 2013 to March 2017, patients taking DOACs were enrolled. Patients underwent VCE. The type and location of small-bowel lesions were registered. Also, (1) the proportion of lesions detected between types of DOAC was evaluated and (2) the hemoglobin (Hb) and serum ferritin levels were compared between patients with and without small-bowel lesions. Results. 33 patients were enrolled, but 4 patients withdrew their consent, and VCE was performed on 29 patients. Eight, 13, and 8 patients received dabigatran, rivaroxaban, and apixaban, respectively. Small-bowel transit was complete in 27 of 29 patients (93.1%). Small-bowel lesions were detected in 23 (79.3%), redness in 12 (41.4%), erosions in 14 (48.3%), and angioectasia in 3 (10.3%) patients, and 6 patients (20.7%) had no abnormalities. Redness and erosions were detected in the upper, middle, or lower portions, but erosions tended to be less frequent in the middle portion (p=0.25, 0.06). Angioectasia was not detected in the lower portion. No patients had active bleeding. The findings did not differ according to the drug. The relationships between the endoscopic findings and the Hb and serum ferritin levels were not significant. Conclusion. Many patients taking DOACs had small-bowel lesions; however, most lesions were relatively mild. Observing small-bowel lesions over longer periods may be necessary in patients taking DOACs. This trial is registered with UMIN000011527.

Main RecommendationsThe 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.

There are multiple indications for luminal imaging of the colon. From assessment of known disease, to diagnosing new pathology; intra-luminal visualisation is the mainstay of gastrointestinal diagnosis. Colonoscopy and radiological imaging are currently the most frequently deployed diagnostic methods. However, both have an associated risk profile, have significant resource pressures and are not universally tolerated. Colon capsule endoscopy (CCE) offers an adjunct to these diagnostic options. In this narrative review the utility of CCE is described. Its current uses, potential benefits and future developments are also discussed.

Continuous navigation information for medical insertion methods including wireless capsule endoscopy is an important feature to guide a medical instrument/object to the targeted location within a hollow organ or internal cavity of the patient in the best possible way. Also, an autonomous medical insertion or swallowable device with a self-contained navigation system would reduce the role of the high-level operator and hence reduce the human-factor mistake and risk of injury. The navigation techniques suggested for Wireless Capsule Endoscopy are image-based that are required to transfer and process a significant amount of data in real-time operation. This would increase the complexity of the system and would be more difficult in dark or liquid environments. A novel navigation system for Wireless Capsule Endoscopy/ordinary endoscopy that does not depend on any external source for operation and can handle the uncertainties of the path even in a dark or liquid environment ( i.e .mucosa) of the human body is presented in this paper. The key element of the system is based on a capacitive-based pressure sensor array mounted on the capsule with the shape of semi-hemisphere. The place of each node is arranged to represent the variation in the latitude and the longitude of the travelling path. The system can acquire the required information to navigate the capsule in three-dimensional space and enhance the safety of the locomotion by monitoring the pressure between the capsule and the ambient environment. The system determines the variation of the path 180° in longitude and latitude with less than (

Introduction and aims: Capsule endoscopy has revolutionized the study of small bowel disorders. Its diagnostic yield, reasons for referral, and frequency of significant endoscopic findings at our institution are unknown. The aims of our study were to describe the reasons for referral, the frequency of significant endoscopic findings, and the diagnostic yield of capsule endoscopy in patients that underwent the procedure for the study of small bowel disorders. Materials and methods: A retrospective study was conducted that included all patients that underwent capsule endoscopy for small bowel disorder evaluation at our institution. The diagnostic yield for significant endoscopic findings, the frequency of significant endoscopic findings, and the reasons for referral for capsule endoscopy were determined. Results: A total of 134 patients were included in the study and 143 capsule endoscopies were performed. Women made up 48.5% of the sample and the mean patient age was 63 years (18.7 standard deviation). The main reasons for referral were suspicion of overt small bowel bleeding (55.9%) and suspicion of occult small bowel bleeding (28.6%). The overall diagnostic yield was 66.4%. The most common significant findings were small bowel angioectasias (52.6%) and small bowel ulcers (38.9%). There were two adverse events (1.3%): one capsule retention that required enteroscopic removal and one asymptomatic bronchoaspiration of the capsule that resolved spontaneously. Conclusions: The frequency of significant endoscopic findings with capsule endoscopy at our institution was different from that reported in other Mexican studies, but the reasons for referral and the diagnostic yield were similar. Resumen: Introducción y objetivos: La cápsula endoscópica ha revolucionado el estudio de patologías del intestino delgado. Desconocemos su rendimiento diagnóstico, motivo de referencia y la frecuencia de hallazgos endoscópicos significativos en nuestra institución. Los objetivos del studio fueron: describir los motivos de referencia, la frecuencia de hallazgos endoscópicos significativos y el rendimiento diagnóstico de la cápsula endoscópica en pacientes sometidos a esta para estudio de patologías de intestino delgado. Material y métodos: Se llevó a cabo un estudio retrospectivo en el cual se incluyeron todos los pacientes a los que se les realizó una cápsula endoscópica para estudio de patología en intestino delgado en nuestra institución. Se determinó el rendimiento diagnóstico para hallazgos endoscópicos significativos, la frecuencia de hallazgos endoscópicos significativos y la frecuencia de los motivos de referencia para cápsula endoscópica. Resultados: Se incluyeron 134 pacientes a los cuales se les realizaron 143 cápsula endoscópica; el 48.5% fueron mujeres, con una edad promedio de 63 años (desviación estándar 18.7). Los principales motivos de referencia fueron sospecha de hemorragia de intestino delgado manifiesta (55.9%) y sospecha de hemorragia de intestino delgado oculta (28.6%). El rendimiento diagnóstico global fue del 66.4%. Los principales hallazgos significativos fueron angioectasias en intestino delgado (52.6%) y úlceras en intestino delgado (38.9%). Hubo 2 eventos adversos (1.3%): una retención de cápsula endoscópica que requirió recuperación por enteroscopia y una broncoaspiración asintomática de cápsula endoscópica que resolvió espontáneamente. Conclusiones: La frecuencia de hallazgos endoscópicos significativos con cápsula endoscópica difiere en comparación con otros estudios en México; sin embargo, los motivos de referencia, así como el rendimiento diagnóstico de esta en nuestra institución, son similares.

Capsule endoscopy (CE) is emerging as an important investigation in inflammatory bowel disease (IBD); common types include the standard small bowel CE and colon CE. More recently, the pan-enteric CE was developed to assess the large and small bowel in patients with Crohn’s disease (CD). Emerging indications include noninvasive assessment for mucosal healing (both in the small bowel and the colon) and detection of postoperative recurrence in patients with CD. Given the increasing adoption, several CE scoring systems have been specifically developed for IBD. The greatest concern with performing CE, par ticularly in CD, is capsule retention, but this can be overcome by performing cross-sectional imaging such as magnetic reso nance enterography and using patency capsules before performing the procedure. The development of software for automated detection of mucosal abnormalities typically seen in IBD may further increase its adoption. (Intest Res 2020;18:265-274)

Capsule endoscopy (CE) is the first-line diagnostic modality for detecting small bowel lesions. CE is non-invasive and does not require sedation, but its movements cannot be controlled, it requires a long time for interpretation, and it has lower image quality compared to wired endoscopy. With the rapid advancement of technology, several methods to solve these problems have been developed. This article describes the ongoing developments regarding external CE locomotion using magnetic force, artificial intelligence-based interpretation, and image-enhancing technologies with the CE system.

Background Indications and diagnostic yield of small-bowel video capsule endoscopy (SB-VCE) are communicated in recent clinical academic guidelines. However, guidelines are based mainly on relatively few, small, selection-biased studies at experienced centers, and thus we lack information on indications and diagnostic yield of SB-VCE in the real-world community setting. The aim of the study was to evaluate indications and diagnostic yield of SB-VCE in the real-world community setting. Methods Our local VCE clinical database was used to identify patients undergoing SB-VCE procedures over a 7-year period (2011–2018). Patients were broadly referred and underwent SB-VCE using PillCam™ SB 2 and SB 3 capsule systems. Procedures were reviewed by local endoscopists, who had undergone similar formal SB-VCE review training. Medical reports of the procedures were composed as such. We retrospectively reviewed all reports and gathered data regarding indications and findings. Diagnostic yield was considered positive if SB-VCE visualized any type of clinically significant pathological finding. Results 536 SB-VCE procedures in 516 patients were included in final assessment. Patient mean (± SD) age was 50 ± 20 years with approximately even female/male ratio (275:241). The overall proportion of positive findings was 42% (225/536). The two main indications were obscure gastrointestinal bleeding (occult/anemia or overt/active, OGIB) of 46% (246/536) and definite/suspected Crohn’s disease (CD) of 39% (210/536). Positive SB-VCE findings were obtained in 44% (108/246) of procedures with indication of OGIB and in 50% (104/210) of procedures with indication of CD. Conclusions The indications for SB-VCE are largely consistent with guidelines but with an apparently relatively low diagnostic yield in our real-world community setting.

A typical capsule endoscopy (CE) case generates tens of thousands of images, with abnormalities often confined to a just few frames. Omni Mode is a novel EndoCapsule software algorithm (Olympus, Tokyo, Japan) that proposes to intelligently remove duplicate images while maintaining accuracy in lesion detection.This prospective multicenter study took place across 9 European centers. Consecutive, unselected CE cases were read conventionally in normal mode, with every captured frame reviewed. Cases were subsequently anonymized and randomly allocated to another center where they were read using Omni Mode. Detected lesions and reading times were recorded, with findings compared between both viewing modes. The clinical significance of lesions was described according to the P classification (P0, P1, and P2). Where a discrepancy in lesion detection in either mode was found, expert blinded review at a consensus meeting was undertaken.The patient population undergoing CE had a mean age of 49.5 years (range, 18-91), with the investigation of anemia or GI bleeding accounting for 71.8% of cases. The average small-bowel transit time was 4 hours, 26 minutes. The mean reading time in normal mode was 42.5 minutes. The use of Omni Mode was significantly faster (P .0001), with an average time saving of 24.6 minutes (95% confidence interval, 22.8-26.9). The 2127 lesions were identified and classified according to the P classification as P0 (1234), P1 (656), and P2 (237). Lesions were identified using both reading modes in 40% (n = 936), and 1186 lesions were identified by either normal or Omni Mode alone. Normal mode interpretation was associated with 647 lesions being missed, giving an accuracy of .70. Omni Mode interpretation led to 539 lesions being missed, with an accuracy of .75. There was no significant difference in clinical conclusions made between either reading mode.This study shows that CE reading times can be reduced by an average of 40%, without any reduction in clinical accuracy.

This paper proposes an ultra-low-power multi-mode baseband transceiver for capsule endoscopy. We set a new specification for capsule endoscopy to achieve ultra-low power and short-latency transceiver. The proposed baseband transceiver can operate multi-mode to transmit ten images per seconds depending on the presence of the lesion and the position of the capsule endoscope. The proposed one does not require memory and optimized all the logic and architecture levels. The proposed BCH decoder uses the early termination scheme to reduce the 51.16% of latency and 45.78% of power consumption, respectively. In addition, the advanced encryption standard (AES) processor protects the biomedical information. As a result, we implemented the proposed multi-mode baseband in Verilog-HDL and synthesized by using the Samsung 65 nm CMOS standard cell library. The proposed baseband shows 10.07 μW (0.9 V, @10 MHz) of total power consumption.

Background and Aims Capsule endoscopy (CE) is an established, noninvasive modality for examining the small bowel. Minimum training requirements are based primarily on guidelines and expert opinion. A validated tool to assess the competence of CE is lacking. In this prospective, multicenter study, we determined the minimum number of CE procedures required to achieve competence during gastroenterology fellowship; validated a capsule competency test (CapCT); and evaluated any correlation between CE competence and endoscopy experience. Methods We included second- and third-year gastroenterology fellows from 3 institutions between 2013 and 2018 in a structured CE training program with supervised CE interpretation. Fellows completed the CapCT with a maximal score of 100. For comparison, expert faculty completed the same CapCT. Trainee competence was defined as a score ≥90% compared with the mean expert score. Fellows were tested after 15, 25, and 35 supervised CE interpretations. CapCT was validated using expert consensus and item analysis. Data were collected on the number of previous endoscopies. Results A total of 68 trainees completed 102 CapCTs. Fourteen CE experts completed the CapCT with a mean score of 94. Mean scores for fellows after 15, 25, and 35 cases were 83, 86, and 87, respectively. Fellows with at least 25 interpretations achieved a mean score ≥84 in all 3 institutions. CapCT item analysis showed high interobserver agreement among expert faculty (k = 0.85). There was no correlation between the scores and the number of endoscopies performed. Conclusion After a structured CE training program, gastroenterology fellows should complete a minimum of 25 supervised CE interpretations before assessing competence using the validated CapCT, regardless of endoscopy experience.

Background Small-bowel mucosal abnormalities that may occur secondary to portal hypertension in patients with liver cirrhosis have an impact on health and quality of life. In spite of the importance of these changes, little is known about the frequency and features of small-bowel changes in cirrhotic patients with portal hypertension. Eighty cirrhotic patients with or without esophageal or gastric varices were recruited in this study as well as 60 age- and sex-matched controls. All study participants underwent capsule endoscopy. In addition, half of the patients and controls were randomized to receive single-balloon enteroscopy. Results The prevalence of small-bowel mucosal changes was statistically significantly higher in cirrhotic patients than in controls; 57% versus 6.7%, respectively (p < 0.05). Cirrhotic patients with portal hypertensive gastropathy showed a significant increase in the small-bowel changes (p < 0.001). Small-bowel changes were significantly higher in patients with higher MELD and Child-Pugh scores (p < 0.001). Moreover, capsule endoscopy was more effective in the detection of small-bowel changes than single-balloon enteroscopy. Conclusions Mucosal changes associated with portal hypertensive enteropathy are more prevalent in cirrhotic patients, regardless of the presence or absence of gastric varices. Small-bowel mucosal changes in patients with portal hypertensive enteropathy were more common in patients who suffered from portal hypertensive gastropathy and were positively correlated with advanced chronic liver disease.

Background: Little is known about capsule endoscopy (CE) findings in patients with intestinal tu berculosis who exhibit small bowel lesions. The aim of the present study was to distinguish be tween Crohn’s disease (CD) and intestinal tuberculosis based on CE findings. Methods: Findings from 55 patients, who underwent CE using PillCam SB CE (Given Imaging, Yo qneam, Israel) between February 2003 and June 2015, were retrospectively analyzed. Results: CE revealed small bowel lesions in 35 of the 55 patients: 19 with CD and 16 with intes tinal tuberculosis. The median age at diagnosis for patients with CD was 26 years and 36 years for those with intestinal tuberculosis. On CE, three parameters, ≥10 ulcers, >3 involved segments and aphthous ulcers, were more common in patients with CD than in those intestinal tuberculo sis. Cobblestoning was observed in five patients with CD and in none with intestinal tuberculosis. The authors hypothesized that a diagnosis of small bowel CD could be made when the number of parameters in CD patients was higher than that for intestinal tuberculosis. The authors calculated that the diagnosis of either CD or intestinal tuberculosis would have been made in 34 of the 35 patients (97%). Conclusion: The number of ulcers and involved segments, and the presence of aphthous ulcers, were significantly higher and more common, respectively, in patients with CD than in those with intestinal tuberculosis. Cobblestoning in the small bowel may highly favor a diagnosis of CD on CE.

Introduction: Appearing in the year 2000, capsule endoscopy revolutionized the study of the small bowel. It is the gold standard for the study of small bowel bleeding and is considered a safe procedure. Objective: The aim of the present study was to identify the indications for, diagnostic yield, and safety of capsule endoscopy in Mexican patients. Materials and methods: A descriptive study was conducted on the first 500 small bowel capsule endoscopies performed at a tertiary care hospital center in Mexico City. Sex, age, type of video camera employed, bowel transit time, referral diagnosis, and capsule endoscopy findings and complications were registered. Results: Mean patient age was 55 years (± 17.63) and 57.9% of the cases were women. Complete visualization of the small bowel was achieved in 420 capsule endoscopies (84%). Mean bowel transit time was 272.25 minutes (± 114.86). The most common indications for the procedure were small bowel bleeding (65.2%), search for neoplasia (14.4%), and Crohn's disease (10.2%). The presence of ulcers was the most common finding in small bowel bleeding (24.8%), followed by angioectasias (18.9%). Capsule retention was the only complication and it presented in 11 patients (2.2%). Conclusions: Capsule endoscopy is a safe and efficacious method for studying the small bowel. The results obtained in Mexican patients were similar to those described in the international literature. The present case series is the largest reported in a Mexican population. Resumen: Introducción: La cápsula endoscópica (CE) revolucionó el estudio del intestino delgado desde su aparición en el año 2000. Es el estándar de oro para el estudio de la hemorragia de intestino delgado (HID) y es considerado un estudio seguro. Objetivo: Identificar las indicaciones, el rendimiento diagnóstico y la seguridad de la CE en pacientes mexicanos. Métodos: Estudio descriptivo de las primeras 500 CE de intestino delgado colocadas en un centro de tercer nivel en México. Se registró el sexo, la edad, el tipo de CE empleada, el tiempo de tránsito intestinal, el diagnóstico de envío, así como los hallazgos y las complicaciones que se presentaron durante la aplicación de las CE. Resultados: La media de edad fue de 55 años (± 17.63) y el 57.9% eran femeninos. Se logró visualización completa del intestino delgado en 420 CE (84%). La media del tiempo de tránsito intestinal fue 272.25 min (± 114.86). Las indicaciones más comunes fueron HID (65.2%), búsqueda de neoplasia (14.4%) y enfermedad de Crohn (10.2%). La presencia de úlceras fue el hallazgo más común en HID (24.8%), seguido de angioectasias (18.9%). La única complicación presentada fue la retención, y se presentó en 11 pacientes (2.2%). Conclusiones: La CE es un método eficaz y seguro para el estudio del intestino delgado. Los resultados obtenidos en pacientes mexicanos fueron similares a los reportados en la literatura internacional. Esta es la mayor experiencia reportada en población mexicana.

Background and aim Although small-bowel angioectasia is reported as the most common cause of bleeding in patients and frequently diagnosed by capsule endoscopy (CE) in patients with obscure gastrointestinal bleeding, a computer-aided detection method has not been established. We developed an artificial intelligence system with deep learning that can automatically detect small-bowel angioectasia in CE images. Methods We trained a deep convolutional neural network (CNN) system based on Single Shot Multibox Detector using 2237 CE images of angioectasia. We assessed its diagnostic accuracy by calculating the area under the receiver operating characteristic curve (ROC-AUC), sensitivity, specificity, positive predictive value, and negative predictive value using an independent test set of 10 488 small-bowel images, including 488 images of small-bowel angioectasia. Results The AUC to detect angioectasia was 0.998. Sensitivity, specificity, positive predictive value, and negative predictive value of CNN were 98.8%, 98.4%, 75.4%, and 99.9%, respectively, at a cut-off value of 0.36 for the probability score. Conclusions We developed and validated a new system based on CNN to automatically detect angioectasia in CE images. This may be well applicable to daily clinical practice to reduce the burden of physicians as well as to reduce oversight.

Compression chip plays a vital role in a wireless capsule endoscopy. It compresses the captured image data to support the limited bandwidth of wireless capsule endoscopy and save the power utilized for transmitting data. This work proposed a near-lossless and low complexity image compression algorithm for wireless capsule endoscopy to provide a high quality image at a good compression ratio with less computational complexity. The algorithm follows four steps, first corner clipping, second RGB-YEN color transform, third fixed threshold DPCM and finally signed Golomb Rice code. The proposed algorithm has a competitive compression ratio of 60.9% compared to other works. It is better than standard JPEG-LS in term of memory usage and computational complexity.

Background: Capsule endoscopy (CE) examination has become the first-line diagnostic method for small bowel disease, and intestinal preparation is a key factor affecting the quality of CE examination. At present, there is no uniform standard for dietary preparation methods before CE at home and abroad, and there are few systematic comparative studies on the choice of dietary methods. Objective: To explore the best method of preparing diet for capsule endoscopy (CE) examination. Methods: 93 Patients who underwent CE examination in the digestive endoscopy center of Wuhan union medical college hospital in October 2019 were randomly divided into 3 groups. Group A (n = 31): 1 day before the examination; a diet with low-residue was given, and 1 day before the examination, fasting was started at 8 p.m. until the examination was completed. Group B (n = 30): a clear liquid diet was followed 1 day before the examination, and fasting was started at 8 p.m. 1 day before the examination until the examination was completed. Group C (n = 32): followed an ordinary diet 1 day before the examination, and began fasting at 8 p.m. 1 day before the examination until the examination was completed. Intestinal preparation of the same drug was performed in 3 groups, and the incidence of side effects and intestinal cleanliness of each group were compared. Results: There was no significant difference in cleanliness between the three groups (P > 0.05). The incidence of side effects in the three groups was 28.13%, 70.00% and 21.88%, respectively. The difference between group A and group B, group C and group B is statistically significant (P < 0.05). Conclusion: The three diet preparation methods of low-residue diet, clear liquid diet and ordinary diet can all achieve good intestinal cleansing effect. Clear liquid diet can not obviously improve the cleanliness of the small intestine, and there are relatively many side effects.

Background: Computer-aided disease detection schemes from wireless capsule endoscopy (WCE) videos have received great attention by the researchers for reducing physicians’ burden due to the time-consuming and risky manual review process. While single disease classification schemes are greatly dealt by the researchers in the past, developing a unified scheme which is capable of detecting multiple gastrointestinal (GI) diseases is very challenging due to the highly irregular behavior of diseased images in terms of color patterns. Method: In this paper, a computer-aided method is developed to detect multiple GI diseases from WCE videos utilizing linear discriminant analysis (LDA) based region of interest (ROI) separation scheme followed by a probabilistic model fitting approach. Commonly in training phase, as pixel-labeled images are available in small number, only the image-level annotations are used for detecting diseases in WCE images, whereas pixel-level knowledge, although a major source for learning the disease characteristics, is left unused. In view of learning the characteristic disease patterns from pixel-labeled images, a set of LDA models are trained which are later used to extract the salient ROI from WCE images both in training and testing stages. The intensity patterns of ROI are then modeled by a suitable probability distribution and the fitted parameters of the distribution are utilized as features in a supervised cascaded classification scheme. Results: For the purpose of validation of the proposed multi-disease detection scheme, a set of pixel-labeled images of bleeding, ulcer and tumor are used to extract the LDA models and then, a large WCE dataset is used for training and testing. A high level of accuracy is achieved even with a small number of pixel-labeled images. Conclusion: Therefore, the proposed scheme is expected to help physicians in reviewing a large number of WCE images to diagnose different GI diseases., An automatic multiple GI disease detection scheme is proposed in this paper based on PDF modeling of multiple linear discriminant analysis-based regions of interest from from wireless capsule endoscopy videos.

BACKGROUND AND AIM Clear visualization of the small bowel is a requirement for satisfactory video capsule endoscopy (VCE). The aim of this study was to identify the optimal dose and timing of polyethylene glycol (PEG) for small bowel preparation before VCE. METHODS A total of 410 patients were enrolled in this prospective randomized trial. All patients fasted for 12 h and ingested 320 mg simethicone 30 min before swallowing the capsule. Patients were randomized into five groups: Group A (no PEG), Group B (1-L PEG, 12 h before VCE), Group C (2-L PEG, 12 h before VCE), Group D (1-L PEG, 4 h before VCE), and Group E (2-L PEG, 4 h before VCE). The primary endpoint was small bowel visualization quality (SBVQ), and the secondary endpoints were patient acceptability and diagnosis rate of VCE. RESULTS Excellent SBVQ was achieved in 27 (32.5%) of Group A, 38 (46.3%) of Group B, 40 (48.2%) of Group C, 55 (66.3%) of Group D, and 43 (54.4%) of Group E. The percentage of excellent SBVQ in Group D was significantly more than in Group A (66.3% vs 32.5%, P

Objective The relation between symptomatology, serology and findings on small bowel capsule endoscopy (SBCE) in patients with coeliac disease (CD) remains unclear. Clarifying such associations will help to determine whether symptoms and serology can predict severity and extent of disease on SBCE. Methods Patients with newly diagnosed CD were recruited. Information on SBCE was recorded. Signs and symptoms at presentation, serological markers and histological classification of the disease in the duodenum were noted. Results Sixty patients with newly diagnosed CD (mean age: 44.9 years, SD: ±17.4, 17-76) were included in this study. Older patients (P = 0.025) and patients presenting with iron deficiency anaemia had more extensive small bowel (SB) involvement (25.7% vs. 13.5%; P = 0.026). Those with weight loss were more likely to have SB involvement beyond the duodenum (37.5% vs. 5.8%; P = 0.027). Patients presenting with iron deficiency anaemia (53.5 vs. 42.4 years; P = 0.038) and weight loss (60.5 vs. 42.4 years; P = 0.009) were significantly older at diagnosis. Serum albumin was lower in those patients diagnosed later on in life (Pearson correlation -0.0361; P = 0.007). There was no significant association between anti-tissue transglutaminase antibody (P = 0.396) and extent of affected SB mucosa. Patients with more severe Marsh scores on histology from the duodenal bulb had more extensive SB involvement (P = 0.017). Conclusions This is the largest study on the use of SBCE in newly diagnosed CD. Older patients are likely to have more extensive disease on SBCE at diagnosis. Symptoms and serology had no impact on the findings on SBCE apart from weight loss and iron deficiency anaemia.

Purpose Wireless Capsule Endoscopy (WCE) is a minimally invasive diagnosis tool for lesion detection in the gastrointestinal tract, reaching places where conventional endoscopy is unable to. However, the significant amount of acquired data leads to difficulties in the diagnosis by the physicians; which can be eased with computer assistance. This paper addresses a method for the automatic detection of tumors in WCE by using a two-step based procedure: region of interest selection and classification. Methods The first step aims to separate abnormal from normal tissue by using automatic segmentation based on a Gaussian Mixture Model (GMM). A modified version of the Anderson method for convergence acceleration of the expectation-maximization (EM) algorithm is proposed. The proposed features for both segmentation and classification are based on the CIELab color space, as a way of bypassing lightness variations, where the L component is discarded. Tissue variability among subjects, light inhomogeneities and even intensity differences among different devices can be overcome by using simultaneously features from both regions. In the second step, an ensemble system with partition of the training data with a new training scheme is proposed. At this stage, the gating network is trained after the experts have been trained decoupling the joint maximization of both modules. The partition module is also used at the test step, leading the incoming data to the most likely expert allowing incremental adaptation by preserving data diversity. Results This algorithm outperforms others based on texture features selected from Wavelets and Curvelets transforms, classified by a regular support vector machine (SVM) in more than 5%. Conclusions This work shows that simpler features can outperform more elaborate ones if appropriately designed. In the current case, luminance was discarded to cope with saturated tissue, facilitating the color perception. Ensemble systems remain an open research field. In the current case, changes in both topo, This work is supported by FCT (Fundacao para a Ciencia e Tecnologia) with the reference Project UID/EEA/04436/2019 and with the PhD Grant SFRH/BD/92143/2013.

Introduction and objective: The SB3 capsule endoscopy system has better image resolution and the capacity to increase the number of images from 2 to 6 frames per second. Small bowel bleeding is the most common indication. The aim To determine if the advances in capsule endoscopy technology increase diagnostic yield in cases of small bowel bleeding, according to the Saurin classification. Material and methods: A retrospective, observational, analytic, cross-sectional study included 100 SB2 capsule endoscopies and 100 SB3 capsule endoscopies in patients that presented with small bowel bleeding. The findings obtained with both systems were evaluated. The lesions identified by the two capsules were categorized using the Saurin classification. The relation between the lesions identified with the SB3 and those found with the SB2 was identified through a logistic regression analysis. Results: In the SB2 capsule endoscopy group, 60% were women, patient age was 59 years (42.2, 73), and intestinal transit time was 271 min (182, 353). In the SB3 group, 57% were women, patient age was 60 years (42.5, 73), and intestinal transit time was 277 min (182, 352). There were no significant differences in the identification of P0 and P2 lesions between the two systems. The SB3 capsule endoscope identified more P1 lesions (p = 0.020, OR: 2.35, 95% CI:1.12-4.90). There was no significant difference in relation to location of the lesions in the small bowel. Conclusions: A greater number of P1 lesions were detected through the technologic advances made in SB3 capsule endoscopy, but the diagnostic yield for P2 lesions was not modified. Resumen: Introducción y objetivo: La cápsula endoscópica (CE) SB3 tiene una mejor resolución de imágenes y capacidad para incrementar de 2 a 6 imágenes obtenidas por segundo. La hemorragia de intestino delgado (HID) es la indicación más común. El objetivo fue determinar si los avances tecnológicos de la CE incrementan el rendimiento diagnóstico en HID de acuerdo a la clasificación de Saurin. Material y métodos: Estudio transversal, observacional, retrospectivo y analítico que incluye 100 SB2 y 100 SB3 en pacientes con HID. Se valoraron los hallazgos obtenidos por ambas CE. Se utilizó la clasificación de Saurin para englobar las lesiones identificadas en las CE. Se realizó una regresión logística para identificar la relación de las lesiones detectadas con la CE SB3 en comparación con la SB2. Resultados: En el grupo de CE SB2 el 60% eran mujeres, edad de 59 años (42.2, 73) y un tiempo de tránsito intestinal de 271 minutos (182, 353). En el grupo de SB3, el 57% eran mujeres, edad de 60 años (42.5, 73) y el tiempo de tránsito intestinal de 277 minutos (182, 352). No se encontraron diferencias significativas para la identificación de lesiones P0 y P2 con ambas CE. La CE SB3 identificó más lesiones P1 (p = 0.020) y una razón de momios de 2.35 (IC 95%; 1.12-4.90). No hubo diferencia significativa por la localización de las lesiones en el intestino delgado. Conclusiones: Los avances tecnológicos permiten a la CE SB3 detectar mayor número de lesiones P1, sin modificar en el rendimiento diagnóstico de las P2. Keywords: Capsule endoscopy, Small intestine, Gastrointestinal hemorrhage, Palabras clave: Cápsula endoscópica, Intestino delgado, Hemorragia gastrointestinal

Wireless capsule endoscopy is an established medical application for the examination of the gastrointestinal tract. However, the robust and precise localization of these capsules is still in need of further scientific investigation. This paper presents an innovative differential magnetic localization method for capsule endoscopy to prevent interference caused by the geomagnetic field. The effect of changing the orientation of the capsule on the localization process was also examined. Simulations using COMSOL Multiphysics with the superimposed geomagnetic field were performed. The Levenberg–Marquardt algorithm was applied in MATLAB to estimate the position and orientation of the capsule. Comparing the proposed differential method with the absolute magnetic localization method under ideal conditions, the mean position and orientation errors were reduced by three orders in magnitude to less than 0.1 mm and 0.1∘ respectively. Even if sensor non-idealities are considered, the simulation-based results reveal that our proposed method is competitive with state-of-the-art geomagnetic compensation methods for static magnetic localization of capsule endoscopes. The achieved localization accuracy by applying the differential method is not dependent on the rotation of the localization system relative to the geomagnetic flux density under the made assumptions and the impact of the magnet orientation is neglectable. It is concluded that the proposed method is capable of preventing all interference whose components are approximately equal at all sensors with identical orientation.

BACKGROUND Small bowel obscured its lesions as secrets which were difficult to diagnose before video capsule endoscopy as a new modality for investigation. Aim of the study Evaluation of video capsule endoscopy in comparison to radiological examination in detection of small bowel lesions. Patients and methods Fifty patients were recruited from Kafrawy Video Capsule Endoscopy Unit of Internal Medicine Department and endoscopy unit of Ain Shams University Hospital. The study included patients with occult or overt GIT bleeding, patients with unexplained microcytic iron deficiency anemia, patients with chronic diarrhea and abdominal pain, with normal upper GI endoscopy and colonoscopy. Exclusion of any patient younger than 18 years old, has intestinal stricture, achalasia, or dysphagia. All patients were studied biochemically with CBC and radiological by CT pelvis and abdomen with IV and oral positive contrast some of them were radiologically examined with CTE or CT mesenteric angiography. All patients were endoscopically examined by OGD, colonoscopy, VCE, and some of them were examined also with enteroscope. Results The study revealed that the detection rate of SB lesions with VCE was 84%. In the current study, (44%) of cases had AVMs, (72.73) % of them were above the age of forty five, and (27.27) % were below the age of forty five. All patients who were investigated with CT mesenteric angiography revealed negative results. In this study (20) % of patients had SB masses and polyps, (70) % of them were at age of forty five or more and only (30) % of them were below the age of forty five. All patients underwent CT pelvis and abdomen with IV and oral positive contrast, and we found that all patients had a negative results regarding the SB lesions. In comparison between CTE and VCE in detection of SB vascular lesions CTE did not detect SB vacular lesions. On the other hand, VCE detected the AVMs in the cases with negative CTE results. In this study one patient (2)% was diagnosed with hookworm infection. All patient underwent for OGD. We found that (20)% of patients had a significant gastric or duodenal lesions (proximal to the papilla) by VCE but missed by upper GI endoscopy. In our study the concomitant of VCE and enteroscope increase the detection of SB vascular lesions than isolated use of VCE only. Conclusion VCE has a high detection rate of SB lesions (84)%. CTE has a low significance in detection of SB vascular lesions and CT mesenteric angiography sensitivity relatively low. AVMs more common with increasing the age. PHE and SB ectopic varicies, were found to be common causes of GIT bleeding in CLD patient. There is a significant rate of missed gastric and duodenal (proximal to the papilla) lesions that the cause of GIT bleeding and unexplained iron deficiency anemia in OGD examination that were detected by VCE.

Background and study aims Two scores have been implemented to standardize capsule endoscopic (CE) findings in patients with Crohn’s disease (CD): Lewis score (LS) and Capsule Endoscopy Crohnʼs Disease Activity Index (CECDAI). Both have limitations and are not well validated in the pediatric population. The aim of our study was to assess a new score (capsule endoscopy – Crohn’s disease index, CE-CD) in pediatric patients with CD and to compare it to preexisting scores. Patients and methods This was a double-center, retrospective study involving pediatric subjects with CD who underwent CE. Correlation analyses between CE-CD, endoscopy scores and noninvasive markers of disease activities were performed. The ability of different CE scores to predict clinical and endoscopic outcomes was evaluated with regression and survival analyses. Results A total of 312 subjects were analyzed. The CE-CD score showed a moderate (Pearson’s r = 0.581, P Conclusions The CE-CD score is a simple, reliable, reproducible, and predictive score for evaluation of small bowel inflammation in pediatric patients with CD. Prospective validation is needed to confirm the applicability of this new index in clinical practice.

Prompted by the core idea of wireless capsule endoscopy as a painless gastrointestinal examination, and the easy adoption of small bowel capsule endoscopy, the armamentarium of the capsule-based imaging platforms has grown to include colon capsule devices as well [...]

Artificial intelligence (AI) has revolutionized the medical diagnostic process of various diseases. Since the manual reading of capsule endoscopy videos is a time-intensive, error-prone process, computerized algorithms have been introduced to automate this process. Over the past decade, the evolution of convolutional neural network (CNN) enabled AI to detect multiple lesions simultaneously with increasing accuracy and sensitivity. Difficulty in validating CNN performance and unique characteristics of capsule endoscopy images make computer-aided reading systems in capsule endoscopy still on a preclinical level. Although AI technology can be used as an auxiliary second observer in capsule endoscopy, it is expected that in the near future, it will effectively reduce the reading time and ultimately become an independent, integrated reading system.

Crohn’s disease (CD) is a chronic inflammatory disorder that may involve the gastrointestinal tract from the mouth to the anus. Habitual disease monitoring is highly important during disease management, aiming to identify and treat disease exacerbations, in order to avoid immediate and future complications. Currently, ilio-clonoscopy is the gold standard for mucosal assessment. However, the procedure is invasive, involves sedation and allows for visualization of the colon and only a small part of the terminal ileum, while most of the small bowel is not visualized. Since CD may involve the whole length of the small bowel, the disease extent might be underestimated. Capsule endoscopy (CE) provides a technology that can screen the entire bowel in a non-invasive procedure, with minimal side effects. In recent years, this technique has gained in popularity for CD evaluation and monitoring. When CE was first introduced, two decades ago, the fear of possible capsule retention in the narrowed inflamed bowel lumen limited its use in CD patients, and a known CD located at the small bowel was even regarded as a relative contraindication for capsule examination. However, at present, as experience using CE in CD patients has accumulated, this procedure has become one of the accepted tools for disease diagnosis and monitoring. In our current review, we summarize the historic change in the indications and contraindications for the usage of capsule endoscopy for the evaluation of CD, and discuss international recommendations regarding CE’s role in CD diagnosis and monitoring.

Wireless capsule endoscopy was first developed to observe the small intestine. A small capsule can be swallowed and images of gastrointestinal tract are taken with natural movement of peristalsis. Application of capsule endoscopy for observing the stomach has also received much attention as a useful alternative to esophagogastroduodenoscopy, but anatomical characteristics of the stomach have demanded technical obstacles that need to be tackled: clear visualization and active movements that could be controlled. Different methods of controlling the capsule within stomach have been studied and magnetic manipulation is the only system that is currently used in clinical settings. Magnets within the capsule can be controlled with a hand-held magnet paddle, robotic arm, and electromagnetic coil system. Studies on healthy volunteers and patients with upper gastrointestinal symptoms have shown that it is a safe and effective alternative method of observing the stomach. This work reviews different magnetic locomotion systems that have been used for observation of the stomach as an emerging new application of wireless capsule endoscopy.

Observing the entire small bowel is difficult due to the presence of complex loops and a long length. Capsule endoscopy (CE) provides a noninvasive and patient-friendly method for visualizing the small bowel and colon. Small bowel capsule endoscopy (SBCE) has a critical role in the diagnosis of small bowel disorders through the direct observation of the entire small bowel mucosa and is becoming the primary diagnostic tool for small bowel diseases. Recently, colon capsule endoscopy (CCE) was also considered safe and feasible for obtaining sufficient colonic images in patients with incomplete colonoscopy, in the absence of bowel obstruction. This review article assesses the current status of CE in terms of the diagnostic yield and the clinical impact of SBCE in patients with obscure gastrointestinal bleeding, who have known or suspected Crohn’s disease, small bowel tumor and inherited polyposis syndrome, celiac disease, and those who have undergone CCE.

Key Points Question Can video capsule endoscopy be safely used as an alternative to standard endoscopic procedures for the initial evaluation of gastrointestinal bleeding during the COVID-19 pandemic? Findings In this cohort study of 146 patients (74 with COVID-19), active bleeding was more frequently identified with video capsule endoscopy as the first strategy (59.5%) compared with conventional endoscopic evaluation (25.0%). The number of invasive procedures was significantly decreased with video capsule endoscopy without increased risk of rebleeding or compromising safety. Meaning The results of this study suggest that video capsule endoscopy can serve as a safe alternative to the standard endoscopic evaluation of gastrointestinal bleeding because it reduces the number of invasive procedures, personnel involved, and use of personal protective equipment., Importance Evaluation of acute gastrointestinal (GI) bleeding using invasive endoscopic procedures comprising the standard of care (SOC)—upper endoscopy and colonoscopy—can expose the endoscopy staff to SARS-CoV-2. Video capsule endoscopy (VCE) does not generate aerosols and only requires 1 person to manage the procedure. Objective To examine the safety of VCE for the initial evaluation of GI bleeding at the peak of the COVID-19 pandemic to identify signs of active bleeding while minimizing patient and personnel exposure, saving personal protective equipment, and avoiding invasive or unnecessary procedures. Design, Setting, and Participants A multicenter (UMass Memorial Medical Center and Louisiana State University Health Sciences Center) retrospective cohort study including 146 patients with COVID-19 who received VCE as the first-line diagnostic modality was conducted from March 15 to June 15, 2020, compared with SOC in January 2020 for evaluation of GI bleeding. The association between treatment and outcomes was estimated using multivariable regression adjusting for potential confounders. Propensity score matching was used to verify the results. Main Outcomes and Measures The primary end point was detection of active bleeding or stigmata of recent bleeding. Secondary end points included the number of patients requiring any invasive procedures, number of additional procedures, rates of rebleeding and rehospitalization, transfusion requirements, and mortality. Results Among 146 patients, 92 (63.0%) were men; mean (SD) age was 64.93 (14.13) years in the COVID-19 group and 61.33 (13.39) years in the SOC group. Active bleeding or stigmata of recent bleeding was observed in 44 (59.5%) patients in the COVID-19 group compared with 18 (25.0%) in the SOC group (adjusted odds ratio, 5.23; 95% CI, 2.23 to 12.27). Only 36 patients (48.7%) in the COVID-19 group required any invasive procedure during the hospitalization compared with 70 (97.2%) in the SOC group (adjusted odds ratio, 0.01; 95% CI, 0.001 to 0.08). The mean (SD) number of invasive procedures was 0.59 (0.77) per patient in the COVID-19 group compared with 1.18 (0.48) per patient in the SOC group (adjusted difference, −0.54; 95% CI, −0.77 to −0.31). Both approaches appeared to be safe and there was no significant difference in transfusion requirements, rebleeding, rehospitalization, or in-hospital mortality. No mortality was attributed to GI bleeding in either group. Conclusions and Relevance In this cohort study, first-line diagnostic evaluation of acute GI bleeding using VCE appeared to be a safe and useful alternative to the traditional approach of upper endoscopy and colonoscopy. Use of VCE was associated with increased detection of active bleeding and a reduced number of invasive procedures and unnecessary exposure of personnel to SARS-CoV-2 and use of personal protective equipment., This cohort study examines the use of video capsule endoscopy vs standard invasive diagnostic procedures to evaluate gastrointestinal (GI) bleeding in patients with COVID-19.

Background and Aims Actual behaviors of drugs in the upper GI tract are not well elucidated. We assess the feasibility of magnetically controlled capsule endoscopy (MCE) in direct and real-time visualization of oral drug behaviors in the stomach. Methods From November 2019 to December 2019, 9 patients with a recent history of upper GI symptoms and 10 healthy volunteers were enrolled in this study. Participants swallowed magnetically controlled capsules to examine the whole stomach. After baseline examination, participants ingested dyed sucralfate gel, and MCE recorded the adhesion time, retention time, and distribution area of sucralfate gel. Outcomes included behaviors of sucralfate gel, safety, and satisfaction assessment of the procedures. Results Adhesion time of sucralfate gel in the abdominal symptoms group was significantly shorter than in the healthy control group (23.76 ± 1.37 minutes vs 31.96 ± 3.09 minutes; P = .032), whereas retention time was longer (98.85 ± 13.94 minutes vs 63.93 ± 8.57 minutes; P = .043). The distribution area of sucralfate gel in the abdominal symptoms group was significantly larger than in healthy control group in cardia (24.29 ± 7.39 vs 9.18 ± 4.06; P < .0001), fundus (18.90 ± 7.08 vs 8.49 ± 4.10; P = .0015), and pylorus (4.64 ± 2.72 vs 0.94 ± 0.90; P = .0019). No adverse events were observed. All participants had a high degree of satisfaction. Conclusions MCE is a feasible and noninvasive tool for direct and real-time visualization of drug behaviors (eg, sucralfate gel) in the stomach. (ClinicalTrials.gov. ID: NCT04327869.), Video Video 1 Magnetically controlled capsule endoscopy direct visualization of drug behaviors in the stomach.

In rare cases, the diagnosis of Crohn’s disease (CD) can only be achieved using small bowel capsule endoscopy (SBCE). We investigate the characteristics of patients with CD only visible on SBCE and assess their disease course. Data of all adult patients with confirmed CD diagnosis based on SBCE with normal endoscopic and cross-sectional imaging findings were retrospectively collected in three tertiary-level hospitals from January 2014 to March 2020. Thirteen patients were included. Ten patients were females, and the mean age at diagnosis was 36 years. Ileum was mostly involved (85%), while duodenum and jejunum were affected in 23% and 38% of the cases, respectively. Nine patients had one segment involved, while four subjects had two or three segments affected. All patients had inflammatory behavior. First treatment consisted of steroids in all cases, and six patients were later treated with immunosuppressant or biologics. After a mean follow-up of 27.5 months, no change in disease behavior, hospitalization, or CD-related surgery was observed. CD only visible at SBCE is a rare condition with a more favorable disease course compared to general CD with a lower rate of complicated behavior, hospitalization, and surgery, despite a similar use of immunosuppressant or biologics.

Background and study aims A reliable outcome measure is needed for bowel preparation quality during capsule endoscopy. Currently, no scales are adequately validated. Our objective was to update an existing small bowel preparation score, create a standardized training module, then determine its inter-rater and intra-rater reliability. Patients and methods Modification to produce standardized scoring of an existing small bowel preparation score was performed followed by development of a training module and validation to create the new Korea-Canada (KODA) score. Twenty readers from a range of backgrounds, including capsule endoscopists, gastroenterology fellows, residents, medical students, and nurses rated bowel cleanliness in 25 capsule videos consisting of 1,233 images, in duplicate 4 weeks apart, after completing the training module. Sequential images selected in 5-minute intervals during small bowel transit were rated on a scale between 0–3 based on the amount of visualized mucosa and the degree of obstruction. Reliability was assessed using estimates of intraclass correlation coefficients (ICCs). Results Intraclass correlation coefficients for inter-rater (ICC 0.81, 95 % CI 0.70–0.87) and intra-rater (ICC 0.92, 95 % CI 0.87–0.94) reliability were almost perfect among the 20 readers. Inter-rater reliability ranged between 0.72 (95 % CI 0.57–0.81) and 0.89 (95 % CI 0.79–0.93) for nurses and residents, respectively. Intra-rater reliability was greater than 0.90 for all groups except for nurses, which was still almost perfect (ICC 0.86, 95 % CI 0.79–0.90). Conclusions Almost perfect inter-rater and intra-rater reliability was observed for the KODA score. This simple score could be used for future clinical trials after completion of the training module.

Visualization of inner gastrointestinal (GI) tract is an important aspect in diagnosis of diseases such as the bleeding and colon cancer. Wireless capsule endoscopy (WCE) provides painless imaging of the GI tract without much discomfort to patients via near-lights imaging model and with burst light emitting diodes (LEDs). This imaging system is designed to minimize battery power and the capsule moves through the GI tract with natural peristalsis movement and the color video data are captured via wireless transmitter in the WCE. Despite the advantages of WCE videos, the obtained frames exhibit uneven illumination and sometimes result in darker regions that may require enhancement afterwards for better visualization of regions of interest. In this work, we extend a human visual system (HVS) based image enhancement model that uses a feature-linking neural network model based on timing precisely of the spiking neurons. Experimental results on various WCE frames show that we can obtain better enhancement of regions of interest and compared to other enhancement approaches in the literature we obtain better quality restorations in general. Further, we show the applicability of our enhancement method on improving the automatic image segmentation, and 3D shape from shading visualization reconstruction indicating that it is viable to be used within a computer-aided diagnosis systems for GI tract diseases.

Wireless capsule endoscopy (WCE) is an effective video technology to diagnose gastrointestinal (GI) diseases, such as bleeding, ulcer, and tumor. In order to avoid a tedious manual review process of long duration WCE video recordings, automatic disease detection schemes have received significant attention from the researchers. In particular, instead of the conventional approach of dealing with a single disease, developing a unified scheme, which is capable of detecting multiple GI diseases, is getting more importance while being challenging. In this paper, a unified computer-aided scheme is developed for detecting multiple GI diseases from WCE videos based on a proposed least-square saliency transformation (LSST) followed by a probabilistic model-fitting approach. Commonly in the training phase, image-level labeling of images is used, as pixel-level annotations are available only for a small number of images. In view of utilizing the knowledge from pixel-level annotated diseased images, an LSST scheme is proposed to extract a set of optimum prior coefficient-vectors which is later used to capture the salient pixels of interest (POI) in a larger WCE image dataset that do not have pixel-annotations. The intensity distributions of salient POI are modeled by a suitable probability density function (PDF) and the fitted PDF parameters are utilized as features in the proposed supervised hierarchical classification scheme. A large number of WCE images obtained from publicly available WCE videos are used for performance evaluation and it is found that the result obtained by the proposed method outperforms the results obtained in case of some state-of-the-art methods.

Colon capsule endoscopy was approved for reimbursement under the national health insurance system of Japan in 2014. Dialysis patients are potentially susceptible to bleeding because of the fragile intestine, impaired platelet function, or oral administration of nonsteroidal antiinflammatory drugs (NSAIDs) or anticoagulants. However, the capsule excretion rate after recommended bowel preparation reportedly ranges from 70% to 90%, and administration of boosters is also necessary. For dialysis patients, liquid loading is a problem. The patient on dialysis has moisture restrictions. The caster oil-based booster had an emission rate of 97%, but required a total water content of 3L. A study was conducted on dialysis patients using a protocol in which castor oil was supplemented with Elobixibat and Lactulose to determine whether booster volume could be reduced and elimination rates improved.

Accurate recognition of polyps is crucial for early colorectal cancer diagnosis and treatment. Wireless capsule endoscopy (WCE) is a noninvasive, wireless imaging tool that allows direct visualization of the entire colon without discomfort to patients and has the potential to revolutionize the screening workup for colorectal diseases. However, current manual review is laborious and time consuming, requiring the undivided concentration of the gastroenterologist. Computational methods that can assist automated polyp recognition will enhance the outcome both in terms of diagnostic accuracy and efficiency of WCE. This review introduces the computer-assisted algorithms as applied to colorectal polyp screening, focusing on the successes of deep-learning-based strategies in the WCE sequences. We survey key applications of WCE polyp recognition, covering deep-learning-based image-level classification, lesion region detection, and pixel-accurate segmentation. We conclude by discussing emerging research challenges, possible trends, and future directions.

Wireless capsule endoscopy (WCE) is a non-invasive diagnosis method that allows recording a video as the capsule travels through the gastrointestinal (GI) tract. The practical drawback is producing a long clinical video in which the review process by an experienced specialist is tedious. Automated summarisation methods can reduce the evaluation time by experts as well as errors in manual interpretation. The proposed approach consists of three main steps as follows: First, an adaptive sliding window singular value decomposition is employed to extract representative video frames. Then, adaptive contrast diffusion is utilised to increase the visibility of WCE frames. At the end stage, a novel knowledge-based method is developed to segment video frames into four topographic zones of GI tract, which are oesophagus, stomach, small intestine and large intestine. The authors have evaluated the proposed framework in the presence of 30 local datasets as well as publicly available KID database. The average recall and precision were estimated by 0.86 and 0.83, and by 0.82 and 0.83 for KID database, respectively. Their results reveal that significant reduction in the review time is feasible using the proposed technique. Quantitative results of summarisation show that the proposed method is more effective than three methods in the literature.

Background Capsule endoscopy (CE) is the preferred diagnostic test of choice in the investigation of obscure gastrointestinal bleeding (OGIB). Although, a conservative strategy is recommended in the short-term, for cases with a negative result from CE, the impact of CE on long-term re-bleeding still remains unclear. Hence, the aim of this study was to determine the long-term re-bleeding rate along with predictors after CE in patients with OGIB. Methods We retrospectively reviewed 216 patients with OGIB, whom had received a CE examination, so as to investigate the cause of obscure GI bleeding; between July 2008 and March 2018. The patient’s characteristics, medication use, CE finding, treatments strategy, re-bleeding episodes and follow-up information were collected from the institutional electronic medical chart and CE database. Re-bleeding free survival was evaluated using Kaplan-Meier curves with log rank test, whilst predictors associated with the re-bleeding episodes were analyzed via the use of Cox proportional hazard model. Results One hundred and thirty-three patients with OGIB, having received CE were enrolled in the analysis. The pool rate of re-bleeding was 26.3% (35/133) during a follow-up duration of 26 months after CE. Patients with positive CE study, without specific treatment, had higher rates of re-bleeding (47.6%) than those with positive study whom received specific treatment (25.7%), and negative study (20.8%) (p = 0.042). Although, the re-bleeding free survival was not significantly different among the groups (log rank test; P = 0.10). Re-bleeding events occurring within 6, 12, and 24 months after CE were 36, 64 and 92%, respectively. The high-frequency re-bleeding etiologies were the small bowel angiodysplasias and abnormal vascular lesions. Furthermore, independent predictors for re-bleeding after CE were patients with cirrhosis (hazard ratio, HR 4.06), incomplete CE visualization (HR 2.97), and a history of previous GI bleeding (HR 2.80). Conclusions The likelihood of re-bleeding after CE was higher in patients with positive CE study than those with negative study. Specific treatments, or therapeutic interventions for patients with detectable lesions reduced the probability of re-bleeding episodes in long-term follow-up. Close follow-up for recurrent bleeding is recommeded for at least 2 years after CE.

Background and study aims Small bowel capsule endoscopy [SBCE) has an established role in investigating suspected small bowel bleeding [SSBB). Identification of a biomarker to predict pathology would maximize utility of this valuable diagnostic modality. This study aimed to investigate if fecal immunochemical test [FIT) could predict likelihood of small bowel pathology on SBCE. Patients and methods Patients referred for SBCE to investigate anaemia or suspected small bowel bleeding were prospectively recruited. All patients had negative upper and lower endoscopy prior to referral. A FIT ≥ 45 ug Hb/g was considered positive. SBCE was positive if a potential source of SSBB was identified. The primary endpoint was correlation between FIT and positive SBCE. Secondary endpoints were correlation between anemia and SBCE and a combination of anemia plus FIT and SBCE. Results Fifty-one patients were included in the final study cohort. 29.4 % had a positive FIT, 33.3 % were anemic, and 25.5 % patients had significant SBCE findings. There was a statistically significant association between positive FIT and pathology on SBCE (OR 12, 95 % CI [2.8 – 51.9), P = 0.001). Sensitivity and specificity of positive FIT in predicting SBCE findings were 69 % and 84 %, respectively. A normal Hb had an NPV of 83 % (OR 0.30, P = 0.09). Combining Hb and FIT was statistically significant in predicting pathology on SBCE (OR 9.14, 67 % PPV, 82 % NPV, P = 0.025). Conclusion FIT ≥ 45 ug Hb/g is a useful tool in predicting small bowel pathology on SBCE. Use of this biomarker alone, or in combination with serum haemoglobin, has value as a screening tool and may help to better triage patients referred for SBCE.