Small-bowel capsule endoscopy: A ten-point contemporary review

Retention of endoscopic capsules in diverticula: Literature review of a capsule endoscopy rarity

Background and study aims This review aimed to provide an updated and comprehensive review of capsule retention within diverticula, shedding light on the characteristics and management of this rare event in capsule endoscopy. Methods A systematic literature search was conducted across multiple databases. All observational studies that reported capsule retention in a diverticulum among complication and outcomes, as well as case reports and series, were included. Manual cross-checking of references was also performed. Two extractors performed abstract and full-text reviews, as well as data-extraction. Results We found 167 references from Pubmed, Embase, and Web Of Science. Sixty-five duplicates were removed and another 71 references were excluded. Crosschecking of references found additional two articles. In total, 32 articles were included, resulting in a total of 34 cases of retained capsules in diverticula. The median age was 69 and the majority of the patients were male (76.5%). The most common retention occurred in Meckel's diverticulum (32.4%) followed by Zenker's diverticulum (20.6%). Investigation of capsule retention was done with x-ray (50%) and computed tomography (CT) scan (44.1%). Seventeen cases (50%) were asymptomatic. Resolution of the retention happened with endoscopy (35.3%) and surgical management (32.4%), as well as self-resolution (20.6%). Conclusions Due to the small number of cases, diverticula are not a risk factor for incomplete capsule endoscopy examination. It affects mainly elderly, male, asymptomatic patients, and typically is diagnosed with x-rays and CT scans. The most common type is Meckel's diverticulum, and endoscopy is the primary management. Capsule endoscopy retentions are extremely rare, with only 34 cases reported since the technology's introduction.

A review of modeling and control of remote-controlled capsule endoscopes

INTRODUCTION

The significance of this review lies in addressing the limitations of passive locomotion in capsule endoscopes, hindering their widespread use in medical applications. The research focuses on evaluating existing miniature in vivo remote-controlled capsule endoscopes, examining their locomotion designs, and working theories to pave the way for overcoming challenges and enhancing their applicability in diagnostic and treatment settings.

AREAS COVERED

This paper explores control methods and dynamic system modeling in the context of self-propelled remote-controlled capsule endoscopes with a two-mass arrangement. The literature search, conducted at Queen Mary University of London Library from 2000 to 2022, utilized a systematic approach starting with the broad keyword 'Capsule Endoscope' and progressively narrowing down to specific aspects such as 'Capsule Endoscope Control' and 'Self-propelled Capsule Endoscope' using various criteria.

EXPERT OPINION

Efficiently driving and controlling remote-controlled capsule endoscopes have the potential to overcome the current limitations in medical technology, offering a viable solution for diagnosing and treating gastrointestinal diseases. Successful control of the remote-controlled capsule endoscope, as demonstrated in this review paper, will lead to a step change in medical engineering, establishing the remote-controlled capsule endoscope as a swift standard in the field.

A systematic review on diagnosis and treatment of gastrointestinal diseases by magnetically controlled capsule endoscopy and artificial intelligence

Background

Magnetically controlled capsule endoscopy (MCCE) is a non-invasive, painless, comfortable, and safe equipment to diagnose gastrointestinal diseases (GID), partially overcoming the shortcomings of conventional endoscopy and wireless capsule endoscopy (WCE). With advancements in technology, the main technical parameters of MCCE have continuously been improved, and MCCE has become more intelligent.

Objectives

The aim of this systematic review was to summarize the research progress of MCCE and artificial intelligence (AI) in the diagnosis and treatment of GID.

Data Sources and Methods

We conducted a systematic search of PubMed and EMBASE for published studies on GID detection of MCCE, physical factors related to MCCE imaging quality, the application of AI in aiding MCCE, and its additional functions. We synergistically reviewed the included studies, extracted relevant data, and made comparisons.

Results

MCCE was confirmed to have the same performance as conventional gastroscopy and WCE in detecting common GID, while it lacks research in detecting early gastric cancer (EGC). The body position and cleanliness of the gastrointestinal tract are the main factors affecting imaging quality. The applications of AI in screening intestinal diseases have been comprehensive, while in the detection of common gastric diseases such as ulcers, it has been developed. MCCE can perform some additional functions, such as observations of drug behavior in the stomach and drug damage to the gastric mucosa. Furthermore, it can be improved to perform a biopsy.

Conclusion

This comprehensive review showed that the MCCE technology has made great progress, but studies on GID detection and treatment by MCCE are in the primary stage. Further studies are required to confirm the performance of MCCE.

Computer-Aided Bleeding Detection Algorithms for Capsule Endoscopy: A Systematic Review

Capsule endoscopy (CE) is a widely used medical imaging tool for the diagnosis of gastrointestinal tract abnormalities like bleeding. However, CE captures a huge number of image frames, constituting a time-consuming and tedious task for medical experts to manually inspect. To address this issue, researchers have focused on computer-aided bleeding detection systems to automatically identify bleeding in real time. This paper presents a systematic review of the available state-of-the-art computer-aided bleeding detection algorithms for capsule endoscopy. The review was carried out by searching five different repositories (Scopus, PubMed, IEEE Xplore, ACM Digital Library, and ScienceDirect) for all original publications on computer-aided bleeding detection published between 2001 and 2023. The Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) methodology was used to perform the review, and 147 full texts of scientific papers were reviewed. The contributions of this paper are: (I) a taxonomy for computer-aided bleeding detection algorithms for capsule endoscopy is identified; (II) the available state-of-the-art computer-aided bleeding detection algorithms, including various color spaces (RGB, HSV, etc.), feature extraction techniques, and classifiers, are discussed; and (III) the most effective algorithms for practical use are identified. Finally, the paper is concluded by providing future direction for computer-aided bleeding detection research.

Tubeless field anaesthesia for surgical removal of an aspirated endoscopy capsule

Capsule endoscopy is a safe, minimally invasive procedure used to investigate gastrointestinal bleeding of unknown origin that persists or recurs after a negative initial endoscopy. The most common adverse effects of capsule endoscopy include abdominal pain, nausea and vomiting. Capsule pulmonary aspiration, although a rare complication, has been reported in the literature. Most reported cases resolve without further medical intervention. In these cases, the capsule is either expelled by coughing, or it re-enters the oropharynx and is then swallowed. In a small number of cases, the capsule remains in the lung, unable to be expectorated. This requires prompt diagnosis and emergency bronchoscopic removal under general anaesthesia. Due to the smooth, rounded surfaces of the capsule, it may be difficult to grasp, and consequently extraction may be technically challenging. The existing literature contains limited documentation on anaesthetic and surgical approaches for managing an aspirated endoscopy capsule. In this case report, we present the management of an aspirated endoscopy capsule in a district general hospital, in which thoracic surgery was not available. Local resources were used to manage this potentially life-threatening complication without patient transfer. In our case, we provided a tubeless field to optimise surgical access. This facilitated the successful surgical extraction of the endoscopy capsule from the left main bronchus.

Video Capsule Endoscopy Plays an Important Role in the Management of Crohn's Disease

Crohn's disease (CD) is a chronic inflammatory disorder characterized by a transmural inflammation that may involve any part of the gastrointestinal tract. An evaluation of small bowel involvement, allowing recognition of disease extent and severity, is important for disease management. Current guidelines recommend the use of capsule endoscopy (CE) as a first-line diagnosis method for suspected small bowel CD. CE has an essential role in monitoring disease activity in established CD patients, as it can assess response to treatment and identify high-risk patients for disease exacerbation and post-operative relapse. Moreover, several studies have shown that CE is the best tool to assess mucosal healing as part of the treat-to-target strategy in CD patients. The PillCam Crohn's capsule is a novel pan-enteric capsule which enables visualization of the whole gastrointestinal tract. It is useful to monitor pan-enteric disease activity, mucosal healing and accordingly allows for the prediction of relapse and response using a single procedure. In addition, the integration of artificial intelligence algorithms has showed improved accuracy rates for automatic ulcer detection and the ability to shorten reading times. In this review, we summarize the main indications and virtue for using CE for the evaluation of CD, as well as its implementation in clinical practice.

Computer vision-based solutions to overcome the limitations of wireless capsule endoscopy

Endoscopic investigation plays a critical role in the diagnosis of gastrointestinal (GI) diseases. Since 2001, Wireless Capsule Endoscopy (WCE) has been available for small bowel exploration and is in continuous development. Over the last decade, WCE has achieved impressive improvements in areas such as miniaturisation, image quality and battery life. As a result, WCE is currently a very useful alternative to wired enteroscopy in the investigation of various small bowel abnormalities and has the potential to become the leading screening technique for the entire gastrointestinal tract. However, commercial solutions still have several limitations, namely incomplete examination and limited diagnostic capacity. These deficiencies are related to technical issues, such as image quality, motion estimation and power consumption management. Computational methods, based on image processing and analysis, can help to overcome these challenges and reduce both the time required by reviewers and human interpretation errors. Research groups have proposed a series of methods including algorithms for locating the capsule or lesion, assessing intestinal motility and improving image quality.In this work, we provide a critical review of computational vision-based methods for WCE image analysis aimed at overcoming the technological challenges of capsules. This article also reviews several representative public datasets used to evaluate the performance of WCE techniques and methods. Finally, some promising solutions of computational methods based on the analysis of multiple-camera endoscopic images are presented.

Recent developments in wireless capsule endoscopy imaging: Compression and summarization techniques

Wireless capsule endoscopy (WCE) can be viewed as an innovative technology introduced in the medical domain to directly visualize the digestive system using a battery-powered electronic capsule. It is considered a desirable substitute for conventional digestive tract diagnostic methods for a comfortable and painless inspection. Despite many benefits, WCE results in poor video quality due to low frame resolution and diagnostic accuracy. Many research groups have presented diversified, low-complexity compression techniques to economize battery power consumed in the radio-frequency transmission of the captured video, which allows for capturing the images at high resolution. Many vision-based computational methods have been developed to improve the diagnostic yield. These methods include approaches for automatically detecting abnormalities and reducing the amount of time needed for video analysis. Though various research works have been put forth in the WCE imaging field, there is still a wide gap between the existing techniques and the current needs. Hence, this article systematically reviews recent WCE video compression and summarization techniques. The review's objectives are as follows: First, to provide the details of the requirement, challenges and design percepts for the low complexity WCE video compressor. Second, to discuss the most recent compression methods, emphasizing simple distributed video coding methods. Next, to review the most recent summarization techniques and the significance of using deep neural networks. Further, this review aims to provide a quantitative analysis of the state-of-the-art methods along with their advantages and drawbacks. At last, to discuss existing problems and possible future directions for building a robust WCE imaging framework.

Octa-nonagenarians can perform video capsule endoscopy safely and with a higher diagnostic yield than 65-79-year-old patients

BACKGROUND

Video capsule endoscopy (VCE) is an effective, noninvasive modality for small bowel (SB) investigation. Its usage in the older adults is rising. However, data in octa-nonagenarians regarding diagnostic yield and motility are lacking. Our aim was to evaluate and compare safety and efficacy of VCE between age subgroups of older adult patients.

METHODS

This was a retrospective study of prospectively documented data. All consecutive VCEs of patients ≥65 years (01/2010-12/2017) were included. Patients unable to swallow the capsule or videos with significant recording technical malfunction were excluded. The cohort was divided into the younger group aged 65-79 years old and octa-nonagenarians aged ≥80 years old. Indications for referral, diagnostic yield and transit times were compared between groups.

RESULTS

A total of 535 VCEs were performed in 499 older adult patients (51.2% males); 82.8% were 65-79 years old and 17.2% were ≥80 years old. The ≥80-year-old group had higher rates of clinically significant findings (52.7% vs. 40.0%, p = 0.025), active bleeding (12.5% vs. 6.5%, p = 0.053) and angioectasia (36.0% vs. 23.4%, p = 0.014). Crohn's disease was newly diagnosed in approximately 8% of the entire cohort and 12% of the ≥80 years old. Anemia was the most common indication in both groups, followed by overt bleeding in the ≥80-year-old group (25% vs. 9.9% in 65-79-year-old group, p < 0.001) and Crohn's disease in the 65-79 years old (17.2% vs. 5.4% in ≥80 years old, p = 0.004). Groups were comparable in transit time and cecal documentation rates.

CONCLUSIONS

In octa-nonagenarians, VCE is as safe as in younger older-adults with a higher diagnostic yield of significant and treatable conditions.

Machine learning techniques to detect bleeding frame and area in wireless capsule endoscopy video

Wireless Capsule Endoscopy (WCE) allows direct visual inspecting of the full digestive system of the patient without invasion and pain, at the price of a long examination by physicians of a large number of photographs. This research presents a new approach to color extraction to differentiate bleeding frames from normal ones and locate more bleeding areas. We have a dual-system suggestion. We use entire color information on the WCE pictures and the pixel-represented clustering approach to get the clustered centers that characterize WCE pictures as words. Then we evaluate the status of a WCE framework using the nearby SVM and K methods (KNN). The classification performance is 95.75% accurate for the AUC 0.9771% and validates the exciting performance for bleeding classification provided by the suggested approach. Second, we present a two-step approach for extracting saliency maps to emphasize bleeding locations with a distinct color channel mixer to build a first-stage salience map. The second stage salience map was taken with optical contrast.We locate bleeding spots following a suitable fusion approach and threshold. Quantitative and qualitative studies demonstrate that our approaches can correctly distinguish bleeding sites from neighborhoods.

Which model of small bowel capsule endoscopy has a better diagnostic yield? A systematic review and meta-analysis

Background and study aims: Small-bowel capsule endoscopy (SBCE) is a safe and efficient method for diagnosis of small-bowel diseases. Since its development, different models have appeared. The aim of this study was to analyze which of the different models of SBCE has the best diagnostic yield. Patients and methods: Extensive medical literature research was reviewed, using MESH terms, searching studies comparing different SBCE types. We analyzed the diagnostic yield of all the comparisons and when there were 2 or more studies that compared the same model of SBCEs, a meta-analysis was performed. Results: Ten eligible studies including 1065 SBCEs procedures were identified. The main indication was occult gastrointestinal bleeding in 9/10 studies. Two of them included anemia, chronic diarrhea and/or chronic abdominal pain. The indication in one article was celiac disease. In 9 studies, different types of SBCEs (MiroCam, Endocapsule, OMOM and CapsoCam) were compared with PillCam (SB, SB2 and SB3). Three studies compared MiroCam vs PillCam and CapsoCam vs PillCam, while two studies contrast Endocapsule vs PillCam. None of the SBCEs show superiority over PillCam [OR 0.78 (95%CI;0.60-1.01)]. One study compared SBCEs other than Pillcam (MiroCam vs Endocapsule). Nine studies did not find statistical differences between SBCEs, one showed better diagnostic yield of Mirocam compared with PillCam SB3 (p=0.02). The difference between these SBCE was not replayed in the metaanalysis [OR 0.77 (95%CI;0.49-1.21)]. Conclusions: Despite the appearance of new SBCE models, there are no differences in diagnostic yield; therefore, SBCE endoscopist’s performance should be based on experience and availability.

Video Capsule Endoscopy in Gastroenterology

Video capsule endoscopy (VCE) is a wireless technology used by gastroenterologists for various indications in their clinical practice. There has been significant improvement in this technology since its start about two decades ago. Specific video capsules have been made to evaluate the small bowel, colon, and esophagus. Now pan-enteric video capsule is available to assess both the small bowel and colon. VCE is a non-invasive procedure that has been tremendously evaluated for various gastrointestinal disorders, particularly small intestinal bleeding. There are specific contraindications and complications of VCE. This procedure has the technical part and video reading part. Newer software programs will come to reduce the reading time. Artificial intelligence is also coming for quick and accurate diagnosis of any positive findings during VCE. VCE is an important diagnostic test in the field of gastroenterology. Although it is an addition to optical endoscopic procedures to visualize the gastrointestinal mucosa, it has advantages and disadvantages.

Precise Bleeding and Red lesions localization from Capsule Endoscopy using Compact U-Net

Wireless capsule endoscopy is a non-invasive and painless procedure to detect anomalies from the gastrointestinal tract. Single examination results in up to 8 hrs of video and requires between 45 - 180 mins for diagnosis depending on the complexity. Image and video computational methods are needed to increase both efficiency and accuracy of the diagnosis. In this paper, a compact U-Net with lesser encoder-decoder pairs is presented, to detect and precisely segment bleeding and red lesions from endoscopy data. The proposed compact U-Net is compared with the original U-Net and also with other methods reported in the literature. The results show the proposed compact network performs on par with the original network but with faster training and lesser memory consumption. Also, the proposed model provided a dice score of 91% outperforming other methods reported on a blind tested WCE dataset with no images from this set used for training.

Automated Bowel Polyp Detection Based on Actively Controlled Capsule Endoscopy: Feasibility Study

This paper presents an active locomotion capsule endoscope system with 5D position sensing and real-time automated polyp detection for small-bowel and colon applications. An electromagnetic actuation system (EMA) consisting of stationary electromagnets is utilized to remotely control a magnetic capsule endoscope with multi-degree-of-freedom locomotion. For position sensing, an electronic system using a magnetic sensor array is built to track the position and orientation of the magnetic capsule during movement. The system is integrated with a deep learning model, named YOLOv3, which can automatically identify colorectal polyps in real-time with an average precision of 85%. The feasibility of the proposed method concerning active locomotion and localization is validated and demonstrated through in vitro experiments in a phantom duodenum. This study provides a high-potential solution for automatic diagnostics of the bowel and colon using an active locomotion capsule endoscope, which can be applied for a clinical site in the future.

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.

Ingestible devices for studying the gastrointestinal physiology and their application in oral biopharmaceutics

Ingestible sensor systems are unique tools for obtaining physiological data from an undisturbed gastrointestinal tract. Since their dimensions correspond to monolithic oral dosage forms, such as enteric coated tablets or hydrogel matrix tablets, they also allow insights into the physiological conditions experienced by non-disintegrating dosage forms on their way through the gastrointestinal tract. In this work, the different ingestible sensor systems which can be used for this purpose are described and their potential applications as well as difficulties and pitfalls with respect to their use are presented. It is also highlighted how the data on transit times, pH, temperature and pressure as well as the data from different animal models commonly used in drug product development such as dogs and pigs have contributed to a deeper mechanistic understanding of oral drug delivery.

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.

[Optimal Bowel Preparation for Capsule Endoscopy and Device-assisted Enteroscopy]

For improved examination of video capsule endoscopy (VCE) and device-assisted enteroscopy (DAE), bowel preparation is an essential issue. Multiple factors like air bubbles, food material in the small bowel, and gastric and small bowel transit time affect the small bowel visualization quality (SBVQ), diagnostic yield (DY) and cecal completion rate (CR). Bowel preparation with polyethylene glycol (PEG) solution enhances SBVQ and DY, but it has no effect on CR. Bowel preparation with PEG solution 2 L is similar to PEG 4 L in SBVQ, DY, and CR. Bowel preparation with fasting or PEG solution combined with anti-foaming agents like simethicone enhance SBVQ, but it has no effect on CR. Bowel preparation with prokinetics is not commonly recommended. Optimal timing for purgative bowel preparation has yet to be established. However, the studies regarding bowel preparation for DAE are not sufficient. European Society of Gastrointestinal Endoscopy (ESGE) recommends 8-12 hours fasting from solid food and 4-6 hours fasting from liquids prior to the antegrade DAE. For retrograde DAE, colonoscopy preparation regimen is recommended. This article reviews the literature and ESGE, 2013 Korean published guidelines regarding bowel preparation for VCE and DAE, following suggestion for optimal bowel preparation for VCE and balloon enteroscopy.

A Descriptive Analysis of Capsule Endoscopy Events in the FDA Manufacturer and User Facility Device Experience (MAUDE) Database

Introduction

The malfunction of capsule endoscopy (CE) devices is a significant reason for the failure of CE procedures, which could hinder and prevent diagnosis. Unfortunately, malfunction-related adverse events (AEs) caused by CE devices are rarely reported in publications. Although most malfunction-related AEs could not lead to physical harm, they could reduce the efficiency of medical care and increase medical costs. The manufacturer and user facility device experience (MAUDE) database, a publicly accessible resource for patient safety, contains not only the common complications of CE but also valuable malfunction-related AEs, which have been underutilized. Therefore, the study aims to discover and analyze the possible AEs associated with CE and demonstrate the utility of the MAUDE reports to promote patient safety.

Materials and Methods

We acquired MAUDE reports of CE systems from January 01, 2008, to July 31, 2020, through a systematic search strategy. We utilized the manufacturers, brand names, and product codes as search terms from which medical device reports including structured data and narrative texts were extracted, followed by a manual review of the narrative texts, reporter occupation, device involved, event type and the phase of the event; finally, patient outcomes were recorded and analyzed as per CE categories and characteristics.

Results

A total of 377 CEs medical device reports were retrieved, and 342 reports were included after reviewing. There were 327 mandatory reports (96%) and 15 voluntary reports (4%). These reports referred to capsule endoscope (n = 213), sensing system (n = 66), patency capsule (n = 38), and capsule delivery device (n = 26). A total of 349 CE-related AEs were identified, including complications (n = 228), malfunction-related AEs (n = 109), and other events (n = 12). The composition of AEs was not the same for the CE devices. Complications were major AEs of capsule endoscope and patency capsule, but malfunction-related AEs were the most common in AEs of sensing systems and capsule delivery devices.

Conclusion

MAUDE serves as an invaluable data source for investigating malfunction-related AEs. In addition to common complications, malfunction of CE devices could threaten patient safety in CE procedures. Improving awareness of the malfunction of CE devices and raising adequate training for staff working in gastrointestinal (GI) endoscopic units could be critical and beneficial in preventing malfunction-related AEs.

Training, Reading, and Reporting for Small Bowel Video Capsule Endoscopy

Video capsule endoscopy (VCE) is an established modality for examining the small bowel. Formal training in interpretation and reporting of VCE examinations, along with assessment of performance metrics, is advocated for all gastroenterology fellowship programs. This review provides an overview of VCE minimum training requirements and competency assessment, cognitive and technical aspects of interpretation, and standardized reporting of findings. In order to optimize and advance the clinical utility of VCE, efforts must continue to promote and encourage consensus and standardization of training, definition and assessment of competence, enhancements of VCE reading tools, and use of appropriate nomenclature in VCE reports.

Video capsule endoscopy: pushing the boundaries with software technology

Video capsule endoscopy (VCE) has transformed imaging of the small bowel as it is a non-invasive and well tolerated modality with excellent diagnostic capabilities. The way we read VCE has not changed much since its introduction nearly two decades ago. Reading is still very time intensive and prone to reader error. This review outlines the evidence regarding software enhancements which aim to address these challenges. These include the suspected blood indicator (SBI), automated fast viewing modes including QuickView, lesion characterization tools such Fuji Intelligent Color Enhancement, and three-dimensional (3D) representation tools. We also outline the exciting new evidence of artificial intelligence (AI) and deep learning (DL), which promises to revolutionize capsule reading. DL algorithms have been developed for identifying organs of origin, intestinal motility events, active bleeding, coeliac disease, polyp detection, hookworms and angioectasias, all with impressively high sensitivity and accuracy. More recently, an algorithm has been created to detect multiple abnormalities with a sensitivity of 99.9% and reading time of only 5.9 minutes. These algorithms will need to be validated robustly. However, it will not be long before we see this in clinical practice, aiding the clinician in rapid and accurate diagnosis.

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.

Small-bowel mucosal changes in Egyptian cirrhotic patients with portal hypertension using capsule endoscopy versus single-balloon enteroscopy

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.

Artificial intelligence that determines the clinical significance of capsule endoscopy images can increase the efficiency of reading

Artificial intelligence (AI), which has demonstrated outstanding achievements in image recognition, can be useful for the tedious capsule endoscopy (CE) reading. We aimed to develop a practical AI-based method that can identify various types of lesions and tried to evaluate the effectiveness of the method under clinical settings. A total of 203,244 CE images were collected from multiple centers selected considering the regional distribution. The AI based on the Inception-Resnet-V2 model was trained with images that were classified into two categories according to their clinical significance. The performance of AI was evaluated with a comparative test involving two groups of reviewers with different experiences. The AI summarized 67,008 (31.89%) images with a probability of more than 0.8 for containing lesions in 210,100 frames of 20 selected CE videos. Using the AI-assisted reading model, reviewers in both the groups exhibited increased lesion detection rates compared to those achieved using the conventional reading model (experts; 34.3%–73.0%; p = 0.029, trainees; 24.7%–53.1%; p = 0.029). The improved result for trainees was comparable to that for the experts (p = 0.057). Further, the AI-assisted reading model significantly shortened the reading time for trainees (1621.0–746.8 min; p = 0.029). Thus, we have developed an AI-assisted reading model that can detect various lesions and can successfully summarize CE images according to clinical significance. The assistance rendered by AI can increase the lesion detection rates of reviewers. Especially, trainees could improve their efficiency of reading as a result of reduced reading time using the AI-assisted model.

Crohn's disease

Crohn's disease is an inflammatory bowel disease that is characterized by chronic inflammation of any part of the gastrointestinal tract, has a progressive and destructive course and is increasing in incidence worldwide. Several factors have been implicated in the cause of Crohn's disease, including a dysregulated immune system, an altered microbiota, genetic susceptibility and environmental factors, but the cause of the disease remains unknown. The onset of the disease at a young age in most cases necessitates prompt but long-term treatment to prevent disease flares and disease progression with intestinal complications. Thus, earlier, more aggressive treatment with biologic therapies or novel small molecules could profoundly change the natural history of the disease and decrease complications and the need for hospitalization and surgery. Although less invasive biomarkers are in development, diagnosis still relies on endoscopy and histological assessment of biopsy specimens. Crohn's disease is a complex disease, and treatment should be personalized to address the underlying pathogenetic mechanism. In the future, disease management might rely on severity scores that incorporate prognostic factors, bowel damage assessment and non-invasive close monitoring of disease activity to reduce the severity of complications.

Comparison of Lewis Score and Capsule Endoscopy Crohn's Disease Activity Index in Patients with Crohn's Disease

BACKGROUND/AIMS

Small bowel capsule endoscopy (SBCE) is used to visualize mucosal inflammatory changes in the small intestine of patients with Crohn's disease (CD). The Lewis score (LS) and Capsule Endoscopy Crohn's Disease Activity Index (CECDAI) are used to evaluate the visualized images. We determined the score disagreement between LS and CECDAI in patients with CD.

METHODS

We evaluated 184 SBCE procedures in 102 CD patients with small bowel lesions. Patients were classified according to the Montreal classification. LS and CECDAI were calculated, and cases with disagreement between the two scores were identified. We investigated the characteristics of disagreement, and analyzed the relationships with the Crohn's Disease Activity Index (CDAI) and C-reactive protein.

RESULTS

LS (504 ± 1160) correlated strongly with CECDAI (6 ± 5.4) (Spearman's rank correlation coefficient ρ = 0.81, p < 0.0001). LS values of 135 and 790 were equivalent to CECDAI values of 4.9 and 6.9, respectively. The inflammatory changes by LS were significantly observed in several tertiles in the CECDAI discrepancy group (LS < 135, CECDAI ≥ 4.9) compared with the normal agreement group (LS < 135, CECDAI < 4.9) (p < 0.0001). In both groups, CDAI was also significantly different between Montreal L1 and L3 groups (p = 0.0232, p = 0.0196, respectively). LS inflammation score was 0 in six cases in the LS discrepancy group (LS ≥ 135, CECDAI ≤ 4.9, n = 10); the high LS scores were in patients with high stricture scores.

CONCLUSIONS

Discrepancies between the LS and CECDAI scores were observed in some patients. Cases with high CECDAI alone exhibited extensive inflammation and high disease activity (clinical symptoms and biomarker levels). CECDAI seems to better reflect active intestinal inflammation than LS.

The Efficacy of 4 Liters of Clear Liquids for Small Bowel Preparation Prior to Video Capsule Endoscopy

BACKGROUND/AIMS

Optimal small bowel (SB) preparation for video capsule endoscopy (VCE) is controversial. Our study aimed to support the use of a specified volume of 4 liters of clear liquids for bowel preparation for VCE.

METHODS

A retrospective review of 284 patients who underwent SB preparation with 2 liters of polyethylene glycol (PEG) and 284 patients who had 4 liters of clear liquid preparation. We analyzed image quality, endoscopic findings, completion rate, and transit times.

RESULTS

The 4-liter clear liquid group had significantly higher mean image quality scores when compared to the PEG group (2.908±0.77 to 2.669±0.64, p<0.0001), as well as more studies with adequate preparation (72% to 64%, p=0.0214). Although the PEG group had more endoscopic findings on VCE (40% to 23%, p<0.0001), there was a significant difference in the indications for the procedure between the groups. There was no difference in the capsule completion rate or SB transit time.

CONCLUSION

Our data demonstrate significantly higher mean image quality scores when using a specified volume of 4 liters of clear liquid compared to 2 liters of PEG. This study supports the growing evidence of the effectiveness of a 4-liter clear liquid SB preparation as opposed to PEG for VCE.

Capsule endoscopy: Is the software TOP 100 a reliable tool in suspected small bowel bleeding?

BACKGROUND

Small bowel capsule endoscopy (SBCE) is the reference standard tool for diagnosing small bowel bleeding (SBB). The "TOP 100", which performs an automatic selection of the 100 images that mostly likely contain abnormalities, emerged as a new functionality of the RAPID Reader® software in 2017.

AIM

To compare the concordance of findings between the standard reading (SR) and the use of TOP 100 in suspected SBB.

METHODS

Retrospective study, including consecutive patients submitted to SBCE for suspected SBB. Two experienced readers performed SR and reported the most important findings. Another experienced reader, who was blinded to the SR results, reviewed all the SBCE videos using TOP 100 and reported the most important findings. The relevant findings were defined as the presence of high bleeding potential lesions (P2).

RESULTS

97 patients were included. The TOP 100 detected 81/97(83.5%) of the P2 lesions, in particular 64/67(95.5%) of the angioectasias and 17/30(56.7%) of the ulcers. The TOP 100 identified all sites of active bleeding (n = 9).

CONCLUSION

The TOP 100 identified all sites of active bleeding, as well as the vast majority of significant lesions (83.5%); in particular, it detected over 95% of the angioectasias. Although SR remains the reference standard in the SBCE review, these findings demonstrate that TOP 100 allows for a quick preview reading constituting an important asset in the identification of lesions that may require priority full review and intervention planning.

Small Bowel Gastrointestinal Bleeding Diagnosis and Management-A Narrative Review

Background: Small bowel bleeding accounts for 5-10% of all gastrointestinal bleeding. Despite advances in imaging, endoscopy and minimally invasive therapeutic techniques, its diagnosis and treatment remains a challenge and a standardized algorithm for approaching suspected small bowel bleeding remains elusive. Furthermore, the choice of investigation is subject to timing of presentation and accessibility to investigations. The aim of this study was to construct a narrative review of recent literature surrounding the diagnosis and management of small bowel bleeding. Methods: A literature review was conducted examining the database pubmed with the following key words and Boolean operators: occult GI bleed OR mesenteric bleed OR gastrointestinal hemorrhage OR GI hemorrhage AND management. Articles were selected and reviewed based on relevance to the research topic. Where necessary, the full text was sought to further assess relevance. Results: In overt GI bleeding, CT angiography and red cell scintigraphy are both feasible and reliable diagnostic imaging modalities if standard endoscopy is negative. Red cell scintigraphy may be advantageous through detection of lower bleeding rates but it is subject to availability. Overt bleeding and a positive CT angiogram or red cell scan improves the diagnostic yield of formal angiography ± embolization. Video capsule endoscopy or double balloon endoscopy can be considered in occult GI bleeding following normal upper and lower endoscopy. Conclusions: Small bowel bleeding remains a rare but significant diagnostic and therapeutic challenge. Technological advances in diagnostics have aided evaluation but have not broadened the range of therapeutic interventions.

Mapping the distribution of small bowel angioectasias

Background: Angioectasias are a prominent cause of small bowel (SB) bleeding frequently identified during capsule endoscopy (CE). Subsequent management depends upon grade/severity and location. There is increasing evidence that the location of SB angioectasias is not random. We aimed to map the distribution of SB angioectasias, and assess whether this impacted clinical outcomes. Materials and methods: Retrospective study examining CEs performed over a 10-year period at a tertiary referral centre. Information regarding number, location, and Saurin classification (P0-2) of SB angioectasias was collected. Clinically significant angioectasias (P1/P2) and active SB bleeding were analysed further. Outcomes of patients with P2 angioectasias or active SB bleeding were recorded. Results: 164 SBCE examinations reported angioectasias. 554 P1-2 angioectasias and active bleeds were seen, 435 (78.52%) within the first tertile of SB transit time (SBTT). 277 (50%) angioectasias were identified within the first 10% of SBTT. 40/75 (53.3%) patients with >1 P2 angioectasia and/or active bleed were referred for intervention. Of initial interventions, 24 patients underwent upper GI endoscopy; 13 underwent double balloon enteroscopy (DBE). 9/37(24.3%) had no identifiable angioectasias on endoscopy. Of those receiving ablative therapy, 20/28 (71.4%) re-presented with iron-deficiency anaemia or bleeding. In this group, average angioectasia position was 15.6% of SBTT, compared with 7.9% in those who did not re-represent (p = 0.344). Patients who re-presented had an average 1.6 additional P1 angioectasias, compared with 7.6 amongst those who did not return (p = 0.017). Conclusions: Clinically significant angioectasias are overwhelmingly located within the proximal SB. The majority are within reach of conventional endoscopy. However, AEs are often multiple and many patients re-present following intervention.

Follow-up on: optimizing lesion detection in small bowel capsule endoscopy and beyond: from present problems to future solutions

This review presents noteworthy advances in clinical and experimental Capsule Endoscopy (CE), focusing on the progress that has been reported over the last 5 years since our previous review on the subject. Areas covered: This study presents the commercially available CE platforms, as well as the advances made in optimizing the diagnostic capabilities of CE. The latter includes recent concept and prototype capsule endoscopes, medical approaches to improve diagnostic yield, and progress in software for enhancing visualization, abnormality detection, and lesion localization. Expert commentary: Currently, moving through the second decade of CE evolution, there are still several open issues and remarkable challenges to overcome.

Association between hypokalemia and small bowel capsule endoscopy completion rates in patients in South China: A prospective single-center study

BACKGROUND/AIMS

Approximately 20-30% of small bowel capsule endoscopies (SBCEs) do not reach the cecum at the completion of the examination. We aimed to determine whether hypokalemia influences the completion rate and small bowel transit time (SBTT) of SBCE.

PATIENTS AND METHODS

From January to December 2017, 112 patients (18-75 years old) who underwent SBCE were assessed consecutively for enrolment in our study. On the day of the procedure, a blood test was performed prior to capsule ingestion. The completion rate, gastric transit time (GTT), SBTT, and diagnostic yield were recorded for each SBCE.

RESULTS

The SBCE completion rate was lower in the hypokalemia group than that in the normal potassium group (55.6% (15/27) vs. 76.5% (65/85), P = 0.036). The median GTT was 55.5 ± 47.1 min in the hypokalemia group and 46.7 ± 44.5 min in the normal potassium group (P > 0.05). The median SBTT was 412.8 ± 123.3 min in the hypokalemia group and 367.3 ± 172.5 min in the normal potassium group (P > 0.05). The diagnostic yields of the hypokalemia and normal potassium groups were 74.1% and 78.8%, respectively (P = 1.00).

CONCLUSION

Hypokalemia may decrease the SBCE completion rate. Physicians should consider the possibility of hypokalemia after bowel preparation because this condition is not rare. Potassium deficiencies should be rectified prior to performing SBCE procedures to increase the SBCE completion rate.

A comprehensive review on the utility of capsule endoscopy in coeliac disease: From computational analysis to the bedside

Small bowel capsule endoscopy (SBCE) can identify macroscopic changes of coeliac disease and assess the extent of disease in the small bowel beyond the duodenum. SBCE has a good sensitivity for the detection of coeliac disease in comparison to histology owing to several ideal features such as a high magnification. It also plays a useful role in detecting complications in patients with refractory coeliac disease. Several studies have been carried out on transforming images obtained from small bowel capsule endoscopy to enable the automated detection of features related to coeliac disease. This review discusses the current roles played by small bowel capsule endoscopy in coeliac disease. It identifies future potential roles of this technique and describes in great detail the role of computational analysis in the detection of coeliac disease and how it can be adapted to current available technology.

Clinical Use of Patency Capsule: A Comprehensive Review of the Literature

The patency capsule is a radiopaque, dissolvable diagnostic tool, similar in shape and size to small bowel capsule endoscopes. It was developed to offer a simple, safe, efficient, and accurate evaluation of small bowel functional patency. Although unable to provide direct visual information regarding the presence and location of strictures, masses, or luminal narrowing of the small bowel, a successful patency test minimizes the risk of retention and allows the safe administration of a capsule endoscope. However, its use entails a low risk of potentially harmful adverse events, which in their majority are indolent and resolve spontaneously. Abdominal pain and symptomatic retention are accountable for the majority of reported adverse events, whereas a limited number of reports describe life-threatening complications, namely intestinal obstruction, perforation, and intestinal ischemia. Computed tomography is the modality of choice for the identification of the exact position of an impacted patency capsule, whilst the use of plain abdominal radiographs should be avoided for the evaluation of the patency capsule position, as they provide false information. Hereby, we present a comprehensive review of the available literature regarding the characteristics, indications, clinical use, effectiveness, and adverse events of the patency capsule.10.1093/ibd/izy152_video1izy152.video15777752348001.

Optimising the performance and interpretation of small bowel capsule endoscopy

Small bowel capsule endoscopy has become a commonly used tool in the investigation of gastrointestinal symptoms and is now widely available in clinical practice. In contrast to conventional endoscopy, there is a lack of clear consensus on when competency is achieved or the way in which capsule endoscopy should be performed in order to maintain quality and clinical accuracy. Here we explore the evidence on the key factors that influence the quality of small bowel capsule endoscopy services.

Development of a computed cleansing score to assess quality of bowel preparation in colon capsule endoscopy

BACKGROUND AND STUDY AIMS

Colon capsule endoscopy (CCE) does not possess an objective and reliable scoring system to assess the quality of visualization of the colon mucosa. The aim of this study was to establish a colonic computed assessment of cleansing (CAC) score able to discriminate "adequately cleansed" from "inadequately cleansed" CCE still frames.

PATIENTS AND METHODS

Twelve normal and complete CCEs, using the Pillcam Colon 2 system (Medtronic, Minnesota, United States), were prospectively selected amongst a database. A CAC score, defined as the ratio of color intensities red over green (R/G ratio), and red over brown (R/(R + G) ratio) was calculated for each extracted colonic frame. After sorting and random selection, two sets of still frames representative of the range of these ratios were obtained. These images were analyzed twice in random order by two experienced CCE readers who were blinded to the CAC scores. A receiver operating characteristic (ROC) curve was forged for both types of ratios and a threshold established, yielding the highest diagnostic performance in terms of adequate cleansing assessment.

RESULTS

Four-hundred-and-eight frames were extracted. Regarding the R/G ratio, a threshold value of 1.55 was calculated, with a sensitivity of 86.5 % and a specificity of 77.7 %. Regarding the R/(R + G) ratio, a threshold value of 0.58 was calculated with a sensitivity of 95.5 % and a specificity of 62.9 %.

CONCLUSION

 The two proposed CAC scores based on the ratio of color intensities come with high sensitivities for discriminating between "adequately cleansed" and "inadequately cleansed" CCE still frames, but they lack specificity. Further refinement, with implementation of additional image parameters, is warranted.

What defines quality in small bowel capsule endoscopy

Small bowel capsule endoscopy is considered a first-line diagnostic tool for the investigation of small bowel diseases. Gastroenterological and endoscopic societies have proposed and established measures known as quality indicators, quality measures or performance measures for the majority of endoscopic procedures, in order to ensure competence, healthcare quality and define areas requiring improvement. However, there is a paucity of publications describing small bowel capsule endoscopy quality indicators. Hereby, we attempt to identify and describe a number of pre-procedure, intra-procedure and post-procedure quality indicators, regarding process measures in small bowel capsule endoscopy, after a comprehensive review of the literature.

Small bowel imaging in Crohn's disease patients

Crohn’s disease (CD) is a lifelong, chronic inflammatory bowel disorder. The small bowel (SB) is involved to varying extents, and the clinical course may vary from an inflammatory type to a more complicated one with stricture, fistula, and abscess formation. Esophagogastroduodenoscopy and ileocolonoscopy with biopsies are the conventional endoscopic techniques that usually establish the diagnosis. On the other hand, CD may affect SB segments that cannot be reached through these procedures. Video capsule endoscopy and enteroscopy are additional endoscopic techniques that may allow further SB evaluation in such circumstances. Computed tomographic enterography, magnetic resonance enterography, and ultrasonography are radiologic techniques that serve as a crucial adjunct to endoscopic assessment. They enable the assessment of parts of the bowel that may be difficult to reach with conventional endoscopy; this allows for the detection of active inflammation, penetrating or stricturing disease, and the appreciation of extraintestinal complications. Both endoscopic and radiologic modalities play a role in establishing the diagnosis of CD, as well as determining the disease extent, activity and response to therapy. This review is intended to evaluate these modalities in terms of specificity, sensitivity, potential side-effects, and limiting factors. This should serve as a guide to the clinician for establishing the most appropriate and reliable test within a particular clinical context.

Capsule endoscopy with PillCamSB2 versus PillCamSB3: has the improvement in technology resulted in a step forward?

AIM

To compare the findings and completion rate of PillCam® SB2 and SB3.

METHODS

This was a retrospective single-center study that included 357 consecutive small bowel capsule endoscopies (SBCE), 173 SB2 and 184 SB3. The data collected included age, gender, capsule type (PillCam® SB2 or SB3), quality of bowel preparation, completion of the examination, gastric and small bowel transit time, small bowel findings, findings in segments other than the small bowel and the detection of specific anatomical markers, such as the Z line and papilla.

RESULTS

The mean age of the patients was 48 years and 66.9% were female. The two main indications were suspicion/staging of inflammatory bowel disease (IBD) and obscure gastrointestinal bleeding (OGIB) (43.7% and 40.3%, respectively). Endoscopic findings were reported in 76.2% of examinations and 53.5% were relevant findings. No significant differences were found between SB2 and SB3 with regard to completion rate (93.6% vs 96.2%, p = 0.27), overall endoscopic findings (73.4% vs 78.8%, p = 0.23), relevant findings (54.3% vs 52.7%, p = 0.76), first tertile findings (43.9% vs 48.9%, p = 0.35), extra-SB findings (23.7% vs 17.3%, p = 0.14), Z line and papilla detection rate (35.9% vs 35.7%, p = 0.97 and 27.1% vs 32.6%, p = 0.32, respectively). With regard to the patient subgroups with suspicion/staging of IBD, significant differences were found in relation to the detection of villous edema and the 3rd tertile findings, thus favoring SB3 (26.3% vs 43.8%, p = 0.02 and 47.4% vs 66.3%, p = 0.02, respectively). Mucosal atrophy was significantly more frequently diagnosed with the PillCam® SB3 in patients with anemia/OGIB (0% vs 8%, p = 0.03).

CONCLUSIONS

Overall, PillCam® SB3 did not improve the diagnostic yield compared to SB2, although it improved the detection of villous atrophy and segmental edema.

Clinical outcome of patients with obscure gastrointestinal bleeding during antithrombotic drug therapy

BACKGROUND

The clinical outcome of patients with obscure gastrointestinal bleeding (OGIB) during antithrombotic drug therapy has not been fully investigated.

METHODS

Patients who underwent video capsule endoscopy (VCE) for the investigation of OGIB at Okayama University Hospital from January 2009 to March 2016 were enrolled. We evaluated the VCE findings, the patterns of OGIB, and the rate of rebleeding within 1 year in antithrombotic drug users and antithrombotic drug nonusers.

RESULTS

A total of 181 patients were enrolled. Among the antithrombotic drug users, the rate of VCE positivity in the patients with overt OGIB was significantly higher in comparison with patients with occult OGIB (45% versus 16%, p = 0.014), whereas there was no significant difference among the antithrombotic drug nonusers (27% versus 26%, p = 1.0). Among the antithrombotic drug users, the rate of rebleeding among the VCE-positive patients was significantly higher in comparison with the VCE-negative patients (50% versus 5.9%, p = 0.011). Moreover, among antithrombotic drug users who did not receive therapeutic intervention, the rate of rebleeding among the VCE-positive patients was significantly higher in comparison with the VCE-negative patients (75% versus 6.3%, p = 0.001). However, among the antithrombotic drug nonusers who did not receive therapeutic intervention, the rebleeding rate of the VCE-positive patients was not significantly different from that of the VCE-negative patients (20% versus 9.4%, p = 0.43).

CONCLUSION

Therapeutic intervention should be considered for patients with overt OGIB who are VCE positive and who use antithrombotic drugs due to the high risk of rebleeding.

Systematic review and meta-analysis: is bowel preparation still necessary in small bowel capsule endoscopy?

INTRODUCTION

Optimal bowel preparation for small bowel capsule endoscopy(SBCE) is controversial. This meta-analysis aimed to investigate the effects of laxatives in SBCE.

METHODS

A comprehensive literature search was conducted for studies investigating the use of laxatives in SBCE. The primary outcome was diagnostic yield(DY) for SB findings; secondary outcomes SB visualization quality(SBVQ) and completion rate(CR). Pooled odds ratios(ORs) with 95% confidence intervals(CIs) and number needed to treat(NNT) were calculated.

RESULTS

Forty studies (4380 patients with laxatives, 2185 without) were included. Laxative use did not improve DY of SB findings overall (OR 1.11 (95%CI 0.85-1.44)) or for significant SB findings (OR 1.10 (95%CI 0.76-1.60)). However, SBVQ improved with the use of laxatives (OR 1.60 (95%CI 1.08-2.06)), NNT 14. The OR for completed SBCE was 1.30 (95%CI 0.95-1.78). Patients given polyethylene glycol(PEG) had lower DY than sodium phosphate(NaP). SBVQ improved more with NaP (NNT 7) than PEG (NNT 53).

CONCLUSIONS

Laxatives do not significantly improve DY or CR in SBCE, but do improve SBQV. The use of laxatives may be beneficial in patients likely to have subtle findings. There are significant differences in methodology/definitions between studies, hence the need for standardized visualization scoring and recording of SBCE findings.

Acoustic Sensing and Ultrasonic Drug Delivery in Multimodal Theranostic Capsule Endoscopy

Video capsule endoscopy (VCE) is now a clinically accepted diagnostic modality in which miniaturized technology, an on-board power supply and wireless telemetry stand as technological foundations for other capsule endoscopy (CE) devices. However, VCE does not provide therapeutic functionality, and research towards therapeutic CE (TCE) has been limited. In this paper, a route towards viable TCE is proposed, based on multiple CE devices including important acoustic sensing and drug delivery components. In this approach, an initial multimodal diagnostic device with high-frequency quantitative microultrasound that complements video imaging allows surface and subsurface visualization and computer-assisted diagnosis. Using focused ultrasound (US) to mark sites of pathology with exogenous fluorescent agents permits follow-up with another device to provide therapy. This is based on an US-mediated targeted drug delivery system with fluorescence imaging guidance. An additional device may then be utilized for treatment verification and monitoring, exploiting the minimally invasive nature of CE. While such a theranostic patient pathway for gastrointestinal treatment is presently incomplete, the description in this paper of previous research and work under way to realize further components for the proposed pathway suggests it is feasible and provides a framework around which to structure further work.