Diagnostic accuracy of multimodal noninvasive follow-up for pediatric ulcerative colitis: A single-center prospective study

OBJECTIVES

Ulcerative colitis (UC) is a chronic inflammatory bowel disease (IBD) often requiring endoscopic evaluations, which can be uncomfortable and costly, especially for children. This study aimed to evaluate the diagnostic accuracy of a noninvasive approach combining fecal calprotectin (FCP), colonic ultrasonography (US), and colon capsule endoscopy (CCE) compared with standard ileocolonoscopy in pediatric UC.

METHODS

UC children were enrolled and underwent FCP and US on Day 0, followed by CCE on Day 1 and ileocolonoscopy on Day 2. All procedures were performed by operators who were blinded to the patient's clinical history and all test results. The accuracy for disease activity and extension of each technique and their combination was assessed and compared. Tolerability and safety were also evaluated.

RESULTS

Thirty-two patients were enrolled (15 males, mean age 13.2 ± 3.2 years). CCE showed a sensitivity of 95% and specificity of 100% in detecting colonic inflammation, with positive predictive value (PPV) and negative predictive value (NPV) of 100% and 92%, respectively. US demonstrated a sensitivity of 85% and specificity of 92%, with PPV and NPV of 94% and 79%. The combination of FCP, US, and CCE achieved 95% sensitivity and 100% specificity, with PPV of 100% and NPV of 92%. The noninvasive approach was better tolerated than colonoscopy (p < 0.05), and no serious adverse events were reported.

CONCLUSION

The noninvasive approach combining fecal calprotectin (FCP), ultrasonography, and colon capsule endoscopy demonstrated high diagnostic accuracy and better tolerability compared with standard ileocolonoscopy in pediatric ulcerative colitis follow-up. Further multicenter studies are needed to confirm these findings and evaluate the reproducibility of this noninvasive approach.

Associations between patient factors and successful colon capsule endoscopy - A prospective cohort study

AIM

To establish patient factors associated with a successful colon capsule endoscopy (CCE) test.

METHOD

This prospective cohort study used data collected from patients who underwent CCE as part of the ScotCap evaluation prior to April 2020. A CCE was defined as successful if the capsule visualized the whole colon and rectum (complete test) with sufficient bowel cleansing to permit assessment of the colonic mucosa (adequate bowel preparation). Factors from patients in symptomatic and surveillance groups were analysed for associations with a successful test, complete test, adequate bowel preparation and requirement for further procedure using univariate, multivariate logistic, least absolute shrinkage and selection operator regression.

RESULTS

Data from 263 symptomatic and 137 surveillance patients were analysed. There was an association between a symptomatic patient's age and a successful test (OR = 0.97, 95% CI: 0.95-0.99), adequate bowel preparation (OR = 0.97, 95% CI: 0.94-1.00) and further procedure requirement (OR = 1.04, 95% CI: 1.02-1.06). An association was found, for symptomatic patients, between a faecal immunochemical test result in the range 10-399 μg/g and a further procedure (OR = 2.32, 95% CI: 1.23-4.48). In patients undergoing surveillance for previous colorectal cancer (OR = 0.42, 95% CI: 0.18-0.97), had previous bowel resection surgery (OR = 0.43, 95% CI: 0.19-0.98) or took a beta blocker medication (OR = 0.32, 95% CI: 0.11-0.88), an association was found with further procedure requirement.

CONCLUSIONS

Among symptomatic patients, younger age was associated with obtaining a successful CCE test. Clinicians could consider patient selection based on these results to improve the rate of successful testing in clinical practice.

Clinical utility of colon capsule endoscopy: a moving target?

The purpose of this article is to provide an overview of white light colon capsule endoscopy's current clinical application, concentrating on its most recent developments. Second-generation colon capsule endoscopy (CCE2) is approved by the FDA for use as an adjunctive test in patients with incomplete colonoscopy and within Europe in patients at average risk, those with incomplete colonoscopies or those unwilling to undergo conventional colonoscopies. Since the publication of European Society of GI Endoscopy guidelines on the use of CCE, there has been a significant increase in comparative studies on the diagnostic yield of CCE. This paper discusses CCE2 in further detail. It explains newly developed colon capsule system and the current status on the use of CCE, it also provides a comprehensive summary of systematic reviews on the implementation of CCE in colorectal cancer screening from a methodological perspective. Patients with ulcerative colitis can benefit from CCE2 in terms of assessing mucosal inflammation. As part of this review, performance of CCE2 for assessing disease severity in ulcerative colitis is compared with colonoscopy. Finally, an assessment if CCE can become a cost-effective clinical service overall.

Study of capsule endoscopy delivery at scale through enhanced artificial intelligence-enabled analysis (the CESCAIL study)

AIM

Lower gastrointestinal (GI) diagnostics have been facing relentless capacity constraints for many years, even before the COVID-19 era. Restrictions from the COVID pandemic have resulted in a significant backlog in lower GI diagnostics. Given recent developments in deep neural networks (DNNs) and the application of artificial intelligence (AI) in endoscopy, automating capsule video analysis is now within reach. Comparable to the efficiency and accuracy of AI applications in small bowel capsule endoscopy, AI in colon capsule analysis will also improve the efficiency of video reading and address the relentless demand on lower GI services. The aim of the CESCAIL study is to determine the feasibility, accuracy and productivity of AI-enabled analysis tools (AiSPEED) for polyp detection compared with the 'gold standard': a conventional care pathway with clinician analysis.

METHOD

This multi-centre, diagnostic accuracy study aims to recruit 674 participants retrospectively and prospectively from centres conducting colon capsule endoscopy (CCE) as part of their standard care pathway. After the study participants have undergone CCE, the colon capsule videos will be uploaded onto two different pathways: AI-enabled video analysis and the gold standard conventional clinician analysis pathway. The reports generated from both pathways will be compared for accuracy (sensitivity and specificity). The reading time can only be compared in the prospective cohort. In addition to validating the AI tool, this study will also provide observational data concerning its use to assess the pathway execution in real-world performance.

RESULTS

The study is currently recruiting participants at multiple centres within the United Kingdom and is at the stage of collecting data.

CONCLUSION

This standard diagnostic accuracy study carries no additional risk to patients as it does not affect the standard care pathway, and hence patient care remains unaffected.

High diagnostic yield despite a lower completion rates for inpatient versus outpatient colon and pan-intestinal capsule endoscopy: a nested case-control study

BACKGROUND

Increased familiarity with capsule endoscopy (CE) has been associated with a growing demand for urgent inpatient procedures. Limited data exists comparing the effect of admission status on colon capsule (CCE) and pan-intestinal capsule (PIC) performance. We aimed to compare the quality of inpatient versus outpatient CCE and PIC studies.

METHODS

A retrospective nested case-control study. Patients were identified from a CE database. PillCam Colon 2 Capsules with standard bowel preparation and booster regimen were used in all studies. Basic demographics and key outcome measures were documented from procedure reports and hospital patient records, and compared between groups.

RESULTS

105 subjects were included, 35 cases and 70 controls. Cases were older, were more frequently referred with active bleeding and had more PICs. The diagnostic yield was high at 77% and was similar in both groups. Completion rates were significantly better for outpatients, 43% (n = 15) v's 71% (n = 50), OR 3, NN3. Neither gender nor age affected completion rates. Completion rates and preparation quality were similar for CCE and PIC inpatient procedures.

CONCLUSION

Inpatient CCE and PIC have a clinical role. There is an increased risk of incomplete transit in inpatients, and strategies to mitigate against this are needed.

Acceptability of alternative technologies compared with faecal immunochemical test and/or colonoscopy in colorectal cancer screening: A systematic review

OBJECTIVE

Colorectal cancer (CRC) is the third most common cancer and the second largest cause of cancer-related death worldwide. Current CRC screening in various countries involves stool-based faecal immunochemical testing (FIT) and/or colonoscopy, yet public uptake remains sub-optimal. This review assessed the literature regarding acceptability of alternative CRC screening modalities compared to standard care in average-risk adults.

METHOD

Systematic searches of MEDLINE, EMBASE, CINAHL, Cochrane and Web of Science were conducted up to February 3^rd, 2022. The alternative interventions examined were computed tomography colonography, flexible sigmoidoscopy, colon capsule endoscopy and blood-based biomarkers. Outcomes for acceptability were uptake, discomfort associated with bowel preparation, discomfort associated with screening procedure, screening preferences and willingness to repeat screening method. A narrative data synthesis was conducted.

RESULTS

Twenty-one studies met the inclusion criteria. Differences between intervention and comparison modalities in uptake did not reach statistical significance in most of the included studies. The findings do suggest FIT as being more acceptable as a screening modality than flexible sigmoidoscopy. There were no consistent significant differences in bowel preparation discomfort, screening procedure discomfort, screening preference and willingness to repeat screening between the standard care and alternative modalities.

CONCLUSION

Current evidence comparing standard colonoscopy and stool-based CRC screening with novel modalities does not demonstrate any clear difference in acceptability. Due to the small number of studies available and included in each screening comparison and lack of observed differences, further research is needed to explore factors influencing acceptability of alternative CRC modalities that might result in improvement in population uptake within different contexts.

Colon capsule retention in a patient with large bowel stenosis due to diverticulosis - a case report

Capsule retention is a rare complication to capsule endoscopy. It is often asymptomatic and resolves itself spontaneously. In some cases, endoscopy or surgery is necessary to remove the capsule. Cases of capsule retention in the colon are not reported very often and precautions in subsequent investigations must be considered. We present a case of a 74-year-old woman who underwent colon capsule endoscopy (CCE) due to a positive fecal immunochemical test. The CCE was incomplete, and the patient was referred to conventional colonoscopy, which was complicated by perforation of the large bowel during the procedure. This lead to a CT scan showing the capsule proximal to a stenotic colon segment which was subsequently surgically removed. In patients who report lack of capsule excretion and stenosis is not verified, colonoscopy can be carried out, but with caution.

Low Colon Capsule Endoscopy (CCE) False Negative Rate for Polyps Excluding Reader Error

BACKGROUND

CCE is a diagnostic tool lacking clinical data on false negative rates. We aimed to assess this rate and the reader/technical error breakdown.

METHODS

False negative CCEs were identified after comparing to a colonoscopy database. Missed pathology characteristics and study indications/quality were collated. Cases were re-read by experts and newly identified lesions/pathologies were verified by an expert panel and categorised as reader/technical errors.

RESULTS

Of 532 CCEs, 203 had an adequately reported comparative colonoscopy, 45 (22.2%) had missed polyps, and 26/45 (57.8%) reached the colonic section with missed pathology. Of the cases, 22 (84.6%) had adequate bowel preparation. Indications included 13 (50%) polyp surveillance, 12 (46%) GI symptoms, 1 (4%) polyp screening. CCE missed 18 (69.2%) diminutive polyps and 8 (30.8%) polyps ≥ 6 mm, 18/26 (69.2%) of these were adenomas. Excluding incomplete CCE correlates, colonoscopy total and significant polyp yield were 97/184 (52.7%) and 50/97 (51.5%), respectively. CCE total polyp and significant polyp false negative rate was 26.8% (26/97) and 16% (8/50), respectively. Following re-reading, reader and technical error was 20/26 (76.9%) and 6/26 (23.1%). Total and significant missed polyp rates were 20.6% (20/97) and 14% (7/50) for reader error, 6.2% (6/97) and 2% (1/50) for technical error.

CONCLUSIONS

False negative CCE rate is not insubstantial and should be factored into clinical decision making.

Artificial intelligence and colon capsule endoscopy: Automatic detection of ulcers and erosions using a convolutional neural network

BACKGROUND AND AIM

Colon capsule endoscopy (CCE) has become a minimally invasive alternative for conventional colonoscopy. Nevertheless, each CCE exam produces between 50 000 and 100 000 frames, making its analysis time-consuming and prone to errors. Convolutional neural networks (CNNs) are a type of artificial intelligence (AI) architecture with high performance in image analysis. This study aims to develop a CNN model for the identification of colonic ulcers and erosions in CCE images.

METHODS

A CNN model was designed using a database of CCE images. A total of 124 CCE exams performed between 2010 and 2020 in two centers were reviewed. For CNN development, a total of 37 319 images were extracted, 33 749 showing normal colonic mucosa and 3570 showing colonic ulcers and erosions. Datasets for CNN training, validation, and testing were created. The performance of the algorithm was evaluated regarding its sensitivity, specificity, positive and negative predictive values, accuracy, and area under the curve.

RESULTS

The network had a sensitivity of 96.9% and a specificity of 99.9% specific for the detection of colonic ulcers and erosions. The algorithm had an overall accuracy of 99.6%. The area under the curve was 1.00. The CNN had an image processing capacity of 90 frames per second.

CONCLUSIONS

The developed algorithm is the first CNN-based model to accurately detect ulcers and erosions in CCE images, also providing a good image processing performance. The development of these AI systems may contribute to improve both the diagnostic and time efficiency of CCE exams, facilitating CCE adoption to routine clinical practice.

Castor Oil in Bowel Preparation Regimens for Colon Capsule Endoscopy: A Systematic Review with Meta-Analysis

Completing colon capsule endoscopy (CCE) investigations rely on successful transit and acceptable bowel preparation quality. We investigated the effect of adding castor oil to the CCE bowel preparation regimen on the completion rate using a meta-analysis of existing literature. We conducted a systematic literature search in PubMed, Web of Science, and Embase. Included studies underwent quality assessment, and data for meta-analysis were extracted. Pooled estimates for excretion rate and acceptable bowel preparation rate were calculated. We identified 72 studies matching our search criteria, and six were included in the meta-analysis. Three of the studies had control groups, although two used historical cohorts. The pooled excretion rate (92%) was significantly higher in patients who received castor oil than in those who did not (73%). No significant difference in acceptable colonic cleanliness was observed. Castor oil has been used in a few studies as a booster for CCE. This meta-analysis shows the potential for this medication to improve excretion rates, and castor oil could be actively considered in conjunction with other emerging laxative regimens in CCE. Still, prospective randomized trials with appropriate control groups should be conducted before any conclusions can be drawn. Prospero ID: CRD42022338939.

The Present and Future of Colorectal Cancer Screening

There have been multiple recent updates for recommendations pertaining to colorectal cancer (CRC) screening. Among the most notable is the recommendation from several guideline-issuing bodies to initiate CRC screening examinations at 45 years of age for individuals at average risk for CRC. Current CRC screening methods include stool-based tests and colon visualization examinations. Currently recommended stool-based tests include fecal immunochemical testing, high-sensitivity guaiac-based fecal occult blood testing, and multitarget stool DNA testing. Visualization examinations include colonoscopy, computed tomography colonography, colon capsule endoscopy, and flexible sigmoidoscopy. Although these screening tests have shown encouraging results for CRC detection, there are important differences between these testing modalities for precursor lesion detection and management. In addition, emerging CRC screening methods are being developed and evaluated. However, additional large, multicenter clinical trials in diverse populations are needed to validate the diagnostic accuracy and generalizability of these new tests. This article reviews the recently updated CRC screening recommendations and current and emerging testing options.

Artificial intelligence to improve polyp detection and screening time in colon capsule endoscopy

Colon Capsule Endoscopy (CCE) is a minimally invasive procedure which is increasingly being used as an alternative to conventional colonoscopy. Videos recorded by the capsule cameras are long and require one or more experts' time to review and identify polyps or other potential intestinal problems that can lead to major health issues. We developed and tested a multi-platform web application, AI-Tool, which embeds a Convolution Neural Network (CNN) to help CCE reviewers. With the help of artificial intelligence, AI-Tool is able to detect images with high probability of containing a polyp and prioritize them during the reviewing process. With the collaboration of 3 experts that reviewed 18 videos, we compared the classical linear review method using RAPID Reader Software v9.0 and the new software we present. Applying the new strategy, reviewing time was reduced by a factor of 6 and polyp detection sensitivity was increased from 81.08 to 87.80%.

Performance of a Deep Learning System for Automatic Diagnosis of Protruding Lesions in Colon Capsule Endoscopy

Background: Colon capsule endoscopy (CCE) is an alternative for patients unwilling or with contraindications for conventional colonoscopy. Colorectal cancer screening may benefit greatly from widespread acceptance of a non-invasive tool such as CCE. However, reviewing CCE exams is a time-consuming process, with risk of overlooking important lesions. We aimed to develop an artificial intelligence (AI) algorithm using a convolutional neural network (CNN) architecture for automatic detection of colonic protruding lesions in CCE images. An anonymized database of CCE images collected from a total of 124 patients was used. This database included images of patients with colonic protruding lesions or patients with normal colonic mucosa or with other pathologic findings. A total of 5715 images were extracted for CNN development. Two image datasets were created and used for training and validation of the CNN. The AUROC for detection of protruding lesions was 0.99. The sensitivity, specificity, PPV and NPV were 90.0%, 99.1%, 98.6% and 93.2%, respectively. The overall accuracy of the network was 95.3%. The developed deep learning algorithm accurately detected protruding lesions in CCE images. The introduction of AI technology to CCE may increase its diagnostic accuracy and acceptance for screening of colorectal neoplasia.

Advances in tests for colorectal cancer screening and diagnosis

INTRODUCTION

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths globally. Nonetheless, with early detection of CRC or its precancerous lesions, mortality, and CRC incidence can be reduced. Although colonoscopy is currently the gold standard for CRC screening and diagnosis, its invasive nature, and troublesome bowel preparation deter patient participation. Therefore, there is a need to expand the use of noninvasive or minimally invasive methods to increase patient compliance.

AREAS COVERED

This review summarizes advances in different methods for CRC screening, including stool bacterial and metagenomic markers, fecal proteins, genetic and epigenetic markers in blood and stools, and imaging modalities. The cost-effectiveness of these methods is also discussed. FIT is more cost-effective compared to virtual colonoscopy, mSEPT9 test, and Multitarget Stool DNA test, while the cost-effectiveness of other noninvasive methods requires further evaluation.

EXPERT OPINION

Recent evidence has well demonstrated the usefulness of gut microbiome and certain fecal bacterial markers in the noninvasive diagnosis of CRC and its precancerous lesions. Many of the fecal biomarkers, from host cells or the gut environment, show better diagnostic sensitivity than FIT. New screening tests based on these fecal biomarkers can be expected to replace FIT with higher cost-effectiveness in the near future.

ScotCap - A large observational cohort study

AIM

The aim of this work was to evaluate the performance of colon capsule endoscopy (CCE) in a lower gastrointestinal diagnostic care pathway.

METHOD

This large multicentre prospective clinical evaluation recruited symptomatic patients (patients requiring investigation of symptoms suggestive of colorectal pathology) and surveillance patients (patients due to undergo surveillance colonoscopy). Patients aged 18 years or over were invited to participate and undergo CCE by a secondary-care clinician if they met the referral criteria for a colonoscopy. The primary outcome was the test completion rate (visualization of the whole colon and rectum). We also measured the need for further tests after CCE.

RESULTS

A total of 733 patients were invited to take part in this evaluation, with 509 patients undergoing CCE. Of these, 316 were symptomatic patients and 193 were surveillance patients. Two hundred and twenty-eight of the 316 symptomatic patients (72%) and 137 of the 193 surveillance patients (71%) had a complete test. It was found that 118/316 (37%) of symptomatic patients required no further test following CCE, while 103/316 (33%) and 81/316 (26%) required a colonoscopy and flexible sigmoidoscopy, respectively. Fifty-three of the 193 surveillance patients (28%) required no further test following CCE, while 104/193 (54%) and 30/193 (16%) required a colonoscopy and flexible sigmoidoscopy, respectively. No patient in this evaluation was diagnosed with colorectal cancer. Two patients experienced serious adverse events - one capsule retention with obstruction and one hospital admission with dehydration due to the bowel preparation.

CONCLUSION

CCE is a safe, well-tolerated diagnostic test which can reduce the proportion of patients requiring colonoscopy, but the test completion rate needs to be improved to match that of lower gastrointestinal endoscopy.

Tripolar Electrode Electrochemical Impedance Spectroscopy for Endoscopic Devices toward Early Colorectal Tumor Detection

Embedded sensors for endoscopy devices have been studied toward a convenient and decision-supportive methodology in colorectal cancer (CRC) diagnosis, but no device could provide direct CRC screening with in situ measurements. In this study, we proposed a millimeter-scale electrical impedance spectroscopy (EIS) device that can be integrated into a biopsy tool in endoscopy for colorectal tumor detection. A minimally invasive tripolar electrode was designed to sense the tissue impedance, and a multilayer neural network was implemented for the classification algorithm. The sensor performance was investigated in terms of sensitivity, reliability, and repeatability using dummy tissues made of agarose hydrogels at various saline concentrations. In addition, an in vivo study was conducted in mice with an implanted CT-26 colon tumor line. The results demonstrated that the prototyped EIS device and algorithm can detect the tumor tissue in suspicious lesions with high sensitivity and specificity of 87.2 and 92.5%, respectively, and a low error of 7.1%. The findings of this study are promising for in situ CRC screening and may advance the diagnostic efficacy of CRC detection during endoscopic procedures.

Capsule Endoscopy in Inflammatory Bowel Disease: When? To Whom?

Capsule endoscopy (CE) has proven to be a valuable diagnostic modality for small bowel diseases over the past 20 years, particularly Crohn's disease (CD), which can affect the entire gastrointestinal tract from the mouth to the anus. CE is not only used for the diagnosis of patients with suspected small bowel CD, but can also be used to assess disease activity, treat-to-target, and postoperative recurrence in patients with established small bowel CD. As CE can detect even mildly non-specific small bowel lesions, a high diagnostic yield is not necessarily indicative of high diagnostic accuracy. Moreover, the cost effectiveness of CE as a third diagnostic test employed usually after ileocolonoscopy and MR or CT enterography is an important consideration. Recently, new developments in colon capsule endoscopy (CCE) have increased the utility of CE in patients with ulcerative colitis (UC) and pan-enteric CD. Although deflation of the colon during the examination and the inability to evaluate dysplasia-associated lesion or mass results in an inherent risk of overestimation or underestimation, the convenience of CCE examination and the risk of flare-up after colonoscopy suggest that CCE could be used more actively in patients with UC.

Diagnostic Accuracy for Per-Patient Polyp Detection of Second-Generation Capsule Endoscopy Compared to Colonoscopy: A Meta-Analysis of Multicenter Studies

Colon capsule endoscopy (CCE) or capsule colonoscopy can be used as colorectal cancer (CRC) screening option. We intended to analyze the concerning literature that compared second-generation CCE to standard colonoscopy for multicenter studies only. A literature search was performed in PubMed, Embase, and Web of Science. Study characteristics related to our research including sensitivity and specificity for per-patient polyps detection (size: ≥ 10 mm and ≥ 6 mm). Meta-analysis was performed using an open meta-analyst. Our research included five studies, involving a total of 1518 patients, with a total of 1305 analyzed patients. The adequate bowel preparation rate ranged from 70% to 90%. The rates of complete CCE transit fluctuated from 80% to 100%. Our meta-analysis illustrated that mean (95% confidence interval) per-patient sensitivity, specificity, and diagnostic odds ratio were: 0.86 (0.82-0.91) (p < 0.001), 0.88 (0.72-0.96) (p < 0.001), and 50.7 (18.5-138.9) (p < 0.001), respectively, for polyps ≥ 6 mm; and 0.86 (0.8-0.91) (p < 0.001), 0.96 (0.92-0.98) (p < 0.001), and 173.5 (98.4-305.8) (p < 0.001), respectively, for polyps ≥ 10 mm. We concluded that CCE had high sensitivity and specificity for per-patient polyps vs. standard colonoscopy. Nevertheless, the comparatively higher rate of unfinished CCEs limits the utilization of CCE for CRC screening.

Feasibility of patency capsule and colon capsule endoscopy in patients with suspected gastrointestinal stenosis: a prospective study

Patency capsule (PC) can evaluate the patency of gastrointestinal (GI) tract. We hypothesized preceding patient selection using PC would improve the successful rate of colon capsule endoscopy (CCE). Therefore, a prospective single-arm study using PC followed by CCE was conducted with a control group of CCE alone. Patients with suspected or known GI stenosis scheduled for CCE were enrolled. CCE was performed only when the PC was excreted out of the body within 33 hours of ingestion. Primary endpoint was the rate of observation of the entire GI tract within the duration of examination. The secondary endpoints were complications and CCE findings. Twenty-three patients (17 men) were enrolled. The mean age was 50.5±19.8 years. Suspected stenotic sites were 8, 5, and 10 in the small, large, and small and large bowel, respectively. Sixteen, 12, and 10 patients had abdominal pain, active inflammatory bowel disease, and history of surgery for suspected stenosis, respectively. Patency of GI tract was confirmed in 96% (22/23) of the patients by administered PC. Of the 22 patients who underwent CCE, the entire GI tract was observed in 86% (19/22). No complications were observed. The median transit times in the small bowel and colon were 99 (21–682) and 160 (5–328) minutes, respectively. CCE findings revealed ulcers, erosions, and diverticula in 5, 9, and 4 patients, respectively. In conclusion, CCE with PC might be a safer and useful modality to observe the large colon for patients with suspected GI stenosis.

Patient-Reported Outcomes and Preferences for Colon Capsule Endoscopy and Colonoscopy: A Systematic Review with Meta-Analysis

Colon capsule endoscopy as an alternative to colonoscopy for the diagnosis of colonic disease may serve as a less invasive and more tolerable investigation for patients. Our aim was to examine patient-reported outcomes for colon capsule endoscopy compared to conventional optical colonoscopy including preference of investigation modality, tolerability and adverse events. A systematic literature search was conducted in Web of Science, PubMed and Embase. Search results were thoroughly screened for in- and exclusion criteria. Included studies underwent assessment of transparency and completeness, after which, data for meta-analysis were extracted. Pooled estimates of patient preference were calculated and heterogeneity was examined including univariate meta-regressions. Patient-reported tolerability and adverse events were reviewed. Out of fourteen included studies, twelve had investigated patient-reported outcomes in patients who had undergone both investigations, whereas in two the patients were randomized between investigations. Pooled patient preferences were estimated to be 52% (CI 95%: 41-63%) for colon capsule endoscopy and 45% (CI 95%: 33-57%) for conventional colonoscopy: not indicating a significant difference. Procedural adverse events were rarely reported by patients for either investigation. The tolerability was high for both colon capsule endoscopy and conventional colonoscopy. Patient preferences for conventional colonoscopy and colon capsule endoscopy were not significantly different. Procedural adverse events were rare and the tolerability for colon capsule endoscopy was consistently reported higher or equal to that of conventional colonoscopy.

The Differential Diagnosis of Colorectal Polyps Using Colon Capsule Endoscopy

Objective Although colorectal polyps (CPs) can be observed with colon capsule endoscopy (CCE), it is difficult to determine the type of polyp using CCE. The objective of this study was to differentiate adenomatous polyps (APs) from hyperplastic polyps (HPs) with CCE. Methods In this single-center retrospective study, an analysis was conducted on the same CPs with both CCE and colonoscopy (CS) and histopathologically diagnosed as AP or HP. The color difference (ΔE) between the polyp surface and the surrounding mucosa was calculated using the CIE1976 L*a*b* color space method on white light (WL), flexible spectral imaging color enhancement (FICE), and blue mode (BM) CP images. We investigated the ability of the ratio of the color differences (ΔE') to differentiate between APs and HPs. Results The size of all 51 polyps (34 APs, 17 HPs) was 7.5±4.6 mm with CCE and 7.3±4.2 mm with CS, and this difference was not significant (p=0.28). The FICEΔE' of APs was 3.3±1.8, which was significantly higher than the FICEΔE' of HPs (1.3±0.6; p<0.001). A receiver operating characteristic analysis showed that FICEΔE' was useful for differentiating between APs and HPs, with an area under the curve of 0.928 (95% confidence interval, 0.843-1). The sensitivity was 91.2%, and the specificity was 88.2% with a cut-off value of 1.758. Conclusion Using FICE on CCE images of CPs and applying the CIELAB color space method, we were able to differentiate between APs and HPs with high accuracy. This method has the potential to reduce unnecessary CS procedures.

Scoring Systems for Clinical Colon Capsule Endoscopy-All You Need to Know

In the constantly developing era of minimal diagnostic invasiveness, the role of colon capsule endoscopy in colonic examination is being increasingly recognised, especially in the context of curtailed endoscopy services due to the COVID-19 pandemic. It is a safe diagnostic tool with low adverse event rates. As with other endoscopic modalities, various colon capsule endoscopy scores allow the standardisation of reporting and reproducibility. As bowel cleanliness affects CCE’s diagnostic yield, a few operator-dependent scores (Leighton–Rex and CC-CLEAR scores) and a computer-dependent score (CAC score) have been developed to grade bowel cleanliness objectively. CCE can be used to monitor IBD mucosal disease activity through the UCEIS and the panenteric CECDAIic score for UC and CD, respectively. CCE may also have a role in CRC screening, given similar sensitivity and specificity rates to conventional colonoscopy to detect colonic polyps ≥ 10 mm and CRC. Given CCE’s diagnostic yield and reproducible clinical scores with high inter-observer agreements, CCE is fast becoming a suitable alternative to conventional colonoscopy in specific patient populations.

Capsule endoscopy - Recent developments and future directions

INTRODUCTION

Capsule endoscopy (CE) is an established modality in the diagnostic algorithm of small bowel (SB) pathology. Its use has expanded for investigation of upper and lower gastrointestinal diseases with similar prototypes.

AREAS COVERED

This review covers the role and recent advances of CE, as a non-invasive investigative tool.

EXPERT OPINION

The use of upper gastrointestinal CE is useful in patients who require surveillance for varices particularly in the current era of the COVID-19 pandemic. It has also shown high accuracy in the detection of upper gastrointestinal hemorrhage in patients presenting with a suspicion of hemorrhage. Findings on CE help to guide further management by device-assisted enteroscopy. The data on colon CE suggest comparable diagnostic accuracy to colonoscopy for polyp detection; however, more evidence is required in the high-risk group. Crohn's CE has become an integral part of the management of patients with Crohn's disease offering a comparative assessment tool post escalation of therapy. Artificial intelligence within CE has demonstrated similar if not better diagnostic yield compared to the human with a significantly shorter reading time. Artificial intelligence is likely to be in-built within CE reading platforms over the next few years minimizing reporting time and human error.

Colon Capsule Endoscopy in Detecting Colonic Diverticula in a Japanese Population

Objective

The assessment of colonic diverticula with colon capsule endoscopy (CCE) in a Japanese population provided unclear results. In this study, we retrospectively reviewed a cohort of Japanese patients who had undergone CCE to assess its safety and usefulness in the diagnosis of colonic diverticula.

Methods

In this study, 175 consecutive Japanese patients who had their entire colon observed via CCE from November 2013 to July 2018 were included. Patients were retrospectively stratified according to age, gender, colonic segment, and symptoms involvement. A multivariable regression analysis was performed to investigate the presence of any correlation among variables. The safety of CCE was assessed in terms of the incidence of adverse events (AEs).

Results

Colonic diverticula were observed in 42.3% of all cases; of those; 36.5% were right-sided, 31.1% were left-sided, and 32.4% were bilateral. Moreover, one to two colonic diverticula were observed in 35.1%, while three or more diverticula were seen in 64.9%. Multivariable analysis showed that age (≥70 years) was positively associated with colonic diverticula, while male gender and the presence of colonic polyps were negatively associated with colonic diverticula. No correlation was found between colonic diverticula and symptoms. There was no significant difference between groups with and without colonic diverticula in the incidence of AEs. AEs were mild in severity, with no severe AE-related bowel preparation and capsule ingestion reported.

Conclusion

CCE was well-tolerated by the participants, and the incidence of colonic diverticula was 42.3%, with one to two and three or more diverticula being found in 35.1% and 64.9%, respectively. There was little difference in the frequency of colonic diverticula formation on the right side, left side, and on both sides. Age was a positive association factor, while male gender and the presence of colorectal polyps were negative association factors. No correlation was found between diverticula and symptoms.

CT Colonography Following Incomplete Colonoscopy: A Systematic Review with Meta-Analysis

Following incomplete colonoscopy (IC) patients often undergo computed tomography colonography (CTC), but colon capsule endoscopy (CCE) may be an alternative. We compared the completion rate, sensitivity and diagnostic yield for polyp detection from CCE and CTC following IC. A systematic literature search resulted in twenty-six studies. Extracted data included inter alia, complete/incomplete investigations and polyp findings. Pooled estimates of completion rates of CCE and CTC and complete colonic view rates (CCE reaching the most proximal point of IC) of CCE were calculated. Per patient diagnostic yields of CCE and CTC were calculated stratified by polyp sizes. CCE completion rate and complete colonic view rate were 76% (CI 95% 68-84%) and 90% (CI 95% 83-95%). CTC completion rate was 98% (CI 95% 96-100%). Diagnostic yields of CTC and CCE were 10% (CI 95% 7-15%) and 37% (CI 95% 30-43%) for any size, 13% (CI 95% 9-18%) and 21% (CI 95% 12-32%) for >5-mm and 4% (CI 95% 2-7%) and 9% (CI 95% 3-17%) for >9-mm polyps. No study performed a reference standard follow-up after CCE/CTC in individuals without findings, rendering sensitivity calculations unfeasible. The increased diagnostic yield of CCE could outweigh its slightly lower complete colonic view rate compared to the superior CTC completion rate. Hence, CCE following IC appears feasible for an introduction to clinical practice. Therefore, randomized studies investigating CCE and/or CTC following incomplete colonoscopy with a golden standard reference for the entire population enabling estimates for sensitivity and specificity are needed.

Multicenter feasibility study of bowel preparation with castor oil for colon capsule endoscopy

BACKGROUND AND AIM

Extensive use of laxatives and incomplete excretion rates are problematic for colon capsule endoscopy (CCE). The aim of the present study was to determine the effectiveness of castor oil as a booster.

METHODS

At four Japanese hospitals, 319 examinees undergoing CCE were enrolled retrospectively. Before and after the introduction of castor oil, other preparation reagents were unchanged.

RESULTS

Of 319 examinees who underwent CCE, 152 and 167 examinees took regimens with castor oil (between November 2013 and June 2016) and without castor oil (between October 2015 and September 2017), respectively. Capsule excretion rates within its battery life in the groups with and without castor oil were 97% and 81%, respectively (P < 0.0001). Multivariate analysis showed that ages younger than 65 years (adjusted odds ratio [OR], 3.00; P = 0.0048), male gender (adjusted OR, 3.20; P = 0.0051), and use of castor oil (adjusted OR, 6.29; P = 0.0003) were predictors of capsule excretion within its battery life. Small bowel transit time was shorter and total volume of lavage and fluid intake was lower with castor oil than without (P = 0.0154 and 0.0013, respectively). Overall adequate cleansing level ratios with and without castor oil were 74% and 83%, respectively (P = 0.0713). Per-examinee sensitivity for polyps ≥6 mm with and without castor oil was 83% and 85%, respectively, with specificities of 80% and 78%, respectively.

CONCLUSION

Bowel preparation with castor oil was effective for improving capsule excretion rate and reducing liquid loading.

Comparison of Capsule Endoscopy and Magnetic Resonance Enterography for the Assessment of Small Bowel Lesions in Crohn's Disease

BACKGROUND AND AIMS

Diagnostic yield of Small Bowel Capsule Endoscopy (SBCE) for the assessment of small bowel (SB) lesions is higher than radiologic imaging techniques. However, magnetic resonance enterography (MRE) data are scarce and inconclusive. Colon Capsule Endoscopy (CCE) is a new capsule modality. The primary aim of our study was to compare MRE and capsule endoscopy (CE) for the assessment of Crohn's disease (CD). The secondary objectives were to compare the diagnostic accuracy of both CE modalities and changes in Montreal classification after each examination.

METHODS

We included 47 patients with established (n = 32) or suspected CD (n = 15). MRE was performed first to rule out strictures. In patients with a suspected stricture by MRE, an Agile Patency Capsule was performed. SB disease activity was measured by MaRIA score (MRE) and Lewis Index (CE).

RESULTS

SB lesions were found in 36 of47 patients with CE and in 21 of47 patients with MRE (76.6% vs 44.7%, P = 0.001). Jejunal inflammation was detected by CE in 31.9% of patients and by MRE in 6.4% of patients (15/47 vs 3/47; P = 0.03); lesions in ileum were detected in 57.4% of patients by CE, and in 21.3% of patients by MRE (27/ 47 vs 10/ 47; P = 0.04). Finally, in terminal ileum, CE showed lesions in 68.1% (32/47) of patients, whereas MRE detected lesions in 38.3% (18/ 47 patients), (P = 0.001). The original Montreal classification was changed in 53.1% of patients (25/ 47) based on CE findings and in 12.7% of patients (6/47) based on MRE findings (P < 0.05).

CONCLUSIONS

In our cohort CE was significantly superior to MRE for detecting SB lesions, mainly superficial and proximal lesions. CE is useful for a appropriate patients' classification according to Montreal classification.

Feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy

Bowel preparation regimens for colon capsule endoscopy are not yet standardized since they are not well optimized. The aim of the present study was to evaluate the feasibility of a novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy. A total of 31 patients were prospectively enrolled. In the novel regimen, on the day prior to examination, a low-fiber diet was permitted, 5 mg mosapride citrate was administered twice (1 h prior to lunch and supper) and 1 l polyethylene glycol was administered in the evening. On the day of the examination, an additional 1 l polyethylene glycol, 5 mg mosapride citrate and 200 mg simethicone were administered before capsule ingestion. Polyethylene glycol booster (0.5 l) was administered twice, at 1 and 4 h following capsule ingestion. Colon cleansing levels, ileocecal valve transit time and completion rate were evaluated. A total of 29 patients were included in the final analysis, 90% of whom achieved adequate preparation of the overall colon. Ileocecal valve transit time was 2.35±0.82 h and completion rate was 79.3%. The results revealed that the novel low-volume and sodium phosphate-free bowel preparation regimen for colon capsule endoscopy was feasible, with adequate colon cleansing and completion rates, and has the potential to be used as an alternative regimen.

Advanced technology for the improvement of adenoma and polyp detection during colonoscopy

Early detection and removal of adenomatous polyps reduces colorectal cancer death. However, many studies have reported that up to 20% of adenomas can be missed during colonoscopy. To improve visualization and reduce the blind spot of the colonic mucosa for an increase in the adenoma detection rate, many endoscopic techniques and technologies have been developed. The benefit of the high-definition endoscope for improving adenoma and polyp detection is marginal. Wide-angle colonoscope has failed to improve adenoma detection compared to standard colonoscopy. Although the cap-assisted colonoscope can reduce cecal intubation times, it does not seem to improve adenoma and polyp detection. The diagnostic accuracy of the colon capsule endoscope is low compared to the conventional colonoscope. Third Eye(®) retroscope(®) , which provides additional retrograde viewing, has revealed significant improvement in adenoma and polyp detection compared to standard colonoscopy. However, this device increases procedural times. Recently developed full-spectrum endoscopy colonoscope and extra-wide-angle-view colonoscope have demonstrated a significantly lower miss rate of polyps. However, clinical trials are mandatory to determine the efficacy of these novel technologies for cancer screening. In addition, education and training for these novel techniques and technologies should seriously be considered to improve adenoma and polyp detection.

Modified bowel preparation regimen for use in second-generation colon capsule endoscopy in patients with ulcerative colitis

BACKGROUND AND AIM

We have reported that second-generation colon capsule endoscopy (CCE-2) might be feasible for assessing the severity of mucosal inflammation in ulcerative colitis (UC). However, because of the low rate (69%) of complete evaluation of the colon and owing to inadequate cleansing. We believe that the method of bowel preparation could be improved by reducing volume. In the present study, we attempted to improve the colon-cleansing regimen in order to optimize the usefulness of CCE-2 in the management of UC patients.

METHODS

Twenty patients with histologically confirmed UC were enrolled. Patients took a maximum 2.2 L lavage solution (polyethylene glycol solution and magnesium citrate) in two or three divided doses. To assess the effectiveness of the modified bowel preparation regimen, we evaluated the rate of total colonobservation, the effectiveness of bowel cleansing, andinterobserver agreement in assessing UC disease activity. We used a four-point grading scale (poor, fair, good, and excellent) for evaluating the quality of bowel cleansing. Matts' endoscopic score was used to evaluate disease activity.

RESULTS

The rate of total colon observation was 85%, and 15 patients (75%) excreted the CCE-2 within 8 h. The proportion of excellent plus good cleansing was approximately 60%. There was a substantial interobserver agreement (κ = 0.777) in assessment of overall cleansing, which was still substantial at the fair cleansing level (κ = 0.700).

CONCLUSION

Using CCE-2, the modified bowel preparation regimen, with reduced volume has the potential to succeed in the evaluation of mucosal severity in UC.

Colon capsule endoscopy is feasible to perform after incomplete colonoscopy and guides further workup in clinical practice

BACKGROUND

Colon capsule endoscopy (CCE) could be an option to examine the colon after incomplete colonoscopy.

OBJECTIVE

To investigate the extent that CCE complements incomplete colonoscopy and guides further workup.

DESIGN

Prospective, follow-up study.

SETTING

Three tertiary-care centers.

PATIENTS

Consecutive outpatients after colonoscopy failure; 1-year study period.

INTERVENTION

Patients underwent CCE either immediately after colonoscopy or were rescheduled. Further investigations were guided by the results of CCE. Patients were followed as long as 2 years.

RESULTS

We studied 75 outpatients; 39 had a screening colonoscopy. One third of the patients underwent CCE immediately after colonoscopy. Overall, CCE reached or went beyond the colon segment at which colonoscopy stopped in 68 patients (91%). CCE technically complemented difficult colonoscopy independently of whether same-day CCE was performed (24 [96%]) or was not performed (44 [88%]). CCE detected additional significant findings in 36% of the same-day CCE cases and in 48% of the rescheduled ones. Two patients in the same-day group and 13 in the rescheduled CCE group underwent further colon examination that revealed additional significant findings in 3 of them. Ten percent of the patients reported mild adverse events (AE). If needed, 63 participants (84%) were willing to repeat CCE. Follow-up has not identified symptomatic missed colon cancers.

LIMITATIONS

Selected patient population, first-generation colon capsule, old preparation scheme.

CONCLUSION

CCE performed immediately or at a scheduled date after colonoscopy failure is feasible and safe. CCE after incomplete colonoscopy appears to yield significant findings, guide further workup, and has high patient acceptance.

A series of images of digestive cancers using Pill Cam COLON2 video capsule endoscopy

Colon capsule endoscopy is regarded as an option to complement or even replace diagnostic colonoscopy in selected cases. Since capsule lacks the capability of taking biopsies, a diagnosis of colon cancer usually requires a further confirmation by colonoscopy. A series of seven patients who had highly suspicious lesions at capsule endoscopy (five-colon tumors, one gastric tumor and one small bowel tumor) and in whom the clinical decision and treatment was solely based on capsule findings, are presented. The diagnosis of cancer was confirmed in all cases by surgery and histology.

CONCLUSION

In selected patients with a high index of clinical suspicion of cancer, PillCam colon 2 capsule endoscopy might be a sufficient tool for diagnosis.

Accuracy and safety of second-generation PillCam COLON capsule for colorectal polyp detection

PillCam COLON capsule endoscopy (CCE) (Given Imaging Ltd, Yoqneam, Israel) is one of the most recent diagnostic, endoscopic technologies designed to explore the colon. CCE is a noninvasive, patient-friendly technique that is able to explore the colon without requiring sedation and air insufflation. The first generation of CCE was released onto the market in 2006 and although it generated great enthusiasm, it showed suboptimal accuracy. Recently, a second-generation system (PillCam COLON 2) (CCE-2) has been developed to increase sensitivity for colorectal polyp detection. In this review, accuracy and safety data for CCE-2 are analyzed.