Diagnostic yield of colon capsule endoscopy for Crohn's disease lesions in the whole gastrointestinal tract

Deep learning and minimally invasive inflammatory activity assessment: a proof-of-concept study for development and score correlation of a panendoscopy convolutional network

Background

Capsule endoscopy (CE) is a valuable tool for assessing inflammation in patients with Crohn's disease (CD). The current standard for evaluating inflammation are validated scores (and clinical laboratory values) like Lewis score (LS), Capsule Endoscopy Crohn's Disease Activity Index (CECDAI), and ELIAKIM. Recent advances in artificial intelligence (AI) have made it possible to automatically select the most relevant frames in CE.

Objectives

In this proof-of-concept study, our objective was to develop an automated scoring system using CE images to objectively grade inflammation.

Design

Pan-enteric CE videos (PillCam Crohn's) performed in CD patients between 09/2020 and 01/2023 were retrospectively reviewed and LS, CECDAI, and ELIAKIM scores were calculated.

Methods

We developed a convolutional neural network-based automated score consisting of the percentage of positive frames selected by the algorithm (for small bowel and colon separately). We correlated clinical data and the validated scores with the artificial intelligence-generated score (AIS).

Results

A total of 61 patients were included. The median LS was 225 (0-6006), CECDAI was 6 (0-33), ELIAKIM was 4 (0-38), and SB_AIS was 0.5659 (0-29.45). We found a strong correlation between SB_AIS and LS, CECDAI, and ELIAKIM scores (Spearman's r = 0.751, r = 0.707, r = 0.655, p = 0.001). We found a strong correlation between LS and ELIAKIM (r = 0.768, p = 0.001) and a very strong correlation between CECDAI and LS (r = 0.854, p = 0.001) and CECDAI and ELIAKIM scores (r = 0.827, p = 0.001).

Conclusion

Our study showed that the AI-generated score had a strong correlation with validated scores indicating that it could serve as an objective and efficient method for evaluating inflammation in CD patients. As a preliminary study, our findings provide a promising basis for future refining of a CE score that may accurately correlate with prognostic factors and aid in the management and treatment of CD patients.

The Diagnostic Utility of Biochemical Markers and Intestinal Ultrasound Compared with Endoscopy in Patients with Crohn's Disease and Ulcerative Colitis: A Systemic Review and Meta-Analysis

Background: Inflammatory bowel disease (IBD) consists of Crohn's disease (CD) and Ulcerative colitis (UC). The main goal of treatment is to obtain mucosal healing via endoscopy. More recently, intestinal ultrasounds, along with biochemical markers, have been increasingly popular as point-of-care testing to monitor treatment response. This systemic review and meta-analysis aimed to assess the diagnostic test performance of ultrasonography and biochemical markers (C-reactive protein and fecal calprotectin) compared with endoscopy for detecting inflammation in IBD. Methods: A comprehensive literature search was conducted using PubMed Medline, EMBASE, ScienceDirect, and CINAHL from 1 January 2018 to 1 January 2024. The included studies were prospective and retrospective observational studies, clinical trials, and cross-sectional studies investigating the diagnostic sensitivity and specificity of ultrasonography, biochemical markers, and endoscopy. Studies were selected based on the Preferred Reporting Items for Systematic Review and Meta-analysis Statement (PRISMA). Results: Of the 1035 studies retrieved, 16 met the inclusion criteria, and most of the included studies were prospective observational studies. Diagnostic test accuracy was conducted, and the pooled sensitivity and specificity of all the studies revealed that ultrasonography has the highest pooled sensitivity, at 85% (95% CI, 78 to 91%), and specificity, at 92% (95% CI, 86 to 96%), as compared with biochemical markers and endoscopy. More specifically, biochemical markers had a pooled sensitivity and specificity of 85% (95% CI, 81 to 87%) and 61% (95% CI, 58 to 64%), respectively, and endoscopy had 60% (95% CI, 52 to 68%) and 82% (95% CI, 76 to 87%), respectively. However, the results also show substantial heterogeneity in the studies because of various populations, protocols, and outcomes in the studies included. This was especially noted in the assessment of biochemical markers, in which a metaregression was performed showing a nonsignificant p-value of 0.8856 for the coefficient. Conclusions: IUS was found to have the highest pooled sensitivity and specificity of all the included studies for diagnosing inflammation in patients with CD and UC, and this, coupled with biochemical markers, can improve diagnostic utility.

Pan-Enteric Capsule Endoscopy: Current Applications and Future Perspectives

Background

The role of capsule endoscopy in the evaluation of the small bowel is well established, and current guidelines position it as a first-line test in a variety of clinical scenarios. The advent of double-headed capsules further enabled the endoscopic assessment of colonic mucosa and the opportunity for a one-step noninvasive examination of the entire bowel (pan-enteric capsule endoscopy [PCE]).

Summary

We reviewed the technical procedure and preparation of patients for PCE, as well as its current clinical applications and future perspectives. In non-stricturing and non-penetrating Crohn's disease affecting the small bowel and colon, PCE monitors disease activity by assessing mucosal healing, a major treatment outcome, with a higher diagnostic yield than cross-sectional imaging or conventional colonoscopy. Also in ulcerative colitis, double-headed capsules have been used to monitor disease activity noninvasively. Currently, validated scoring systems have been specifically devised for these double-headed capsules and permit a standardized assessment of the inflammatory burden. In suspected mid-lower digestive bleeding, some exploratory studies have demonstrated the feasibility and high diagnostic yield of PCE, which may work as a filter indicating which patients may benefit of further invasive procedures, namely, for planned hemostatic procedures. The possibility of using PCE is also discussed in the context of polyposis syndromes with simultaneous involvement of the small intestine and colon.

Key Messages

PCE is a feasible, effective, and safe diagnostic procedure to evaluate the small bowel and colon. It has been increasingly explored in the setting of inflammatory bowel diseases and, more recently, in suspected mid-lower digestive bleeding. PCE is expected to reduce the demand for invasive procedures and expand the scope of noninvasive intestinal evaluation in the coming future.

Capsule endoscopy and panendoscopy: A journey to the future of gastrointestinal endoscopy

In 2000, the small bowel capsule revolutionized the management of patients with small bowel disorders. Currently, the technological development achieved by the new models of double-headed endoscopic capsules, as miniaturized devices to evaluate the small bowel and colon [pan-intestinal capsule endoscopy (PCE)], makes this non-invasive procedure a disruptive concept for the management of patients with digestive disorders. This technology is expected to identify which patients will require conventional invasive endoscopic procedures (colonoscopy or balloon-assisted enteroscopy), based on the lesions detected by the capsule, i.e., those with an indication for biopsies or endoscopic treatment. The use of PCE in patients with inflammatory bowel diseases, namely Crohn's disease, as well as in patients with iron deficiency anaemia and/or overt gastrointestinal (GI) bleeding, after a non-diagnostic upper endoscopy (esophagogastroduodenoscopy), enables an effective, safe and comfortable way to identify patients with relevant lesions, who should undergo subsequent invasive endoscopic procedures. The recent development of magnetically controlled capsule endoscopy to evaluate the upper GI tract, is a further step towards the possibility of an entirely non-invasive assessment of all the segments of the digestive tract, from mouth-to-anus, meeting the expectations of the early developers of capsule endoscopy.

Smart Endoscopy Is Greener Endoscopy: Leveraging Artificial Intelligence and Blockchain Technologies to Drive Sustainability in Digestive Health Care

The surge in the implementation of artificial intelligence (AI) in recent years has permeated many aspects of our life, and health care is no exception. Whereas this technology can offer clear benefits, some of the problems associated with its use have also been recognised and brought into question, for example, its environmental impact. In a similar fashion, health care also has a significant environmental impact, and it requires a considerable source of greenhouse gases. Whereas efforts are being made to reduce the footprint of AI tools, here, we were specifically interested in how employing AI tools in gastroenterology departments, and in particular in conjunction with capsule endoscopy, can reduce the carbon footprint associated with digestive health care while offering improvements, particularly in terms of diagnostic accuracy. We address the different ways that leveraging AI applications can reduce the carbon footprint associated with all types of capsule endoscopy examinations. Moreover, we contemplate how the incorporation of other technologies, such as blockchain technology, into digestive health care can help ensure the sustainability of this clinical speciality and by extension, health care in general.

Middle small-bowel segment Lewis score may predict long-term outcomes among patients with quiescent Crohn's disease

Background

Video capsule endoscopy (VCE) has been proven to accurately diagnose small-bowel inflammation and predict flares among patients with quiescent Crohn's disease (CD). However, data regarding its predictive role in this population over an extended follow-up are scarce.

Objectives

To predict clinical exacerbation and to assess the yield of Lewis score in identifying CD patients with future clinical exacerbation during an extended follow-up (>24 months).

Design

A post hoc analysis study.

Methods

Adult patients with quiescent small-bowel CD who were followed with VCE, inflammatory biomarkers and magnetic resonance enterography in a prospective study (between 2013 and 2018). We extracted extended clinical data (up to April 2022). The primary composite outcome (i.e. clinical exacerbation) was defined as intestinal surgery, endoscopic dilation, CD-related admission, corticosteroid administration, or biological/immunomodulator treatment change during follow-up.

Results

Of the 61 patients in the study [median age 29 (24-37) years, male 57.4%, biologic treatment 46.7%], 18 patients met the primary outcome during an extended follow-up [median 58.0 (34.5-93.0) months]. On univariable analysis, complicated [hazard ratio (HR) 7.348, p = 0.002] and stricturing disease phenotype (HR 5.305, p = 0.001) were associated with higher risk for clinical exacerbation during follow-up. A baseline VCE middle small-bowel segment Lewis score (midLS) ⩾ 135 identified patients with future exacerbation [AUC (area under the curve) 0.767, 95% confidence interval (CI) 0.633-0.902, p = 0.001, HR 6.317, 93% negative predictive value], whereas the AUC of the conventional Lewis score was 0.734 (95% CI: 0.589-0.879, p = 0.004). Sensitivity analysis restricted to patients with either complicated (n = 34) or stricturing (n = 26) disease phenotype revealed that midLS still predicted clinical exacerbation during follow-up (AUC 0.747/0.753, respectively), in these patients.

Conclusion

MidLS predicts treatment failure in quiescent CD patients (median follow-up of 5 years) independently of disease phenotype.

Patency capsule: A novel independent predictor for long-term outcomes among patients with quiescent Crohn's disease

INTRODUCTION

Patency capsule (PC) is a recommended procedure to rule-out small-bowel stenosis before video capsule endoscopy (VCE). We examined future clinical outcomes among patients with failed-PC versus patients in whom PC had passed (passed-PC).

METHODS

A Post-hoc analysis of two prospective cohort studies of adult patients with quiescent small-bowel CD that underwent PC between 2013-2020. The primary composite-outcome was the need for intestinal-surgery or endoscopic-dilation during follow-up in patients with or without failed-PC.

RESULTS

A total of 190 patients were included (47-failed PC, 143-passed PC, median follow-up 34.12 months). Patients with a failed-PC had higher rates of the primary composite-outcome (21.3% vs. 1.4%, Hazard ratio [HR] 20.3, 95% confidence interval [CI] 4.4-93.7, p<0.001) and also secondary outcomes including intestinal-surgery (14.9% vs. 0.70%, p<0.001), endoscopic-dilation (14.9% vs. 0.70%, p<0.001), admissions (23.3% vs. 5.7%, p<0.001) and clinical-flares (43.9% vs. 27.7%, p=0.005) during follow-up compared with controls. Failed-PC was the only statistically significant factor for surgery and/or endoscopic-dilation, regardless of a B2/B3 phenotype at baseline. In sensitivity-analyses restricted only to patients with stricturing phenotype (n=73), failed-PC still predicted worse long-term composite-outcome (HR 8.68 95% CI 1.72-43.68, p=0.002). Of the 190 patients ingesting a PC, only one patient with a failed-PC had 48 hours of self-limiting mild symptoms.

DISCUSSION

Clinically-stable CD patients with failed-PC have worse long-term clinical outcomes than those without, independently of CD phenotype. Standalone PC may serve as a novel, safe and affordable prognostic examination, to identify patients with quiescent CD who have a higher risk for future worse clinical outcomes.

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.

The diagnostic yield of pan-enteric capsule endoscopy in inflammatory bowel disease: A systematic review and meta-analysis

BACKGROUND AND AIM

Capsule endoscopy (CE) is a non-invasive diagnostic modality enabling real time video imaging of the gastrointestinal (GI) mucosa. Pan-enteric capsule endoscopy (PCE) is now able to thoroughly assess the entire GI tract, including for inflammatory bowel disease (IBD). Our aim was to evaluate the diagnostic accuracy of PCEs in IBD.

METHODS

We comprehensively searched electronic databases (MEDLINE, SCOPUS, EMBASE, and Cochrane Central Register of Controlled Trials) for studies comparing the diagnostic accuracy of PCE with endoscopic evaluation, intestinal ultrasound or magnetic resonance enterography (MRE). Data were analyzed by calculating forest plots and the use of the I² statistic for heterogeneity.

RESULTS

Fourteen studies were identified, with seven studies evaluating PCE diagnostic yield in Crohn's disease (CD) and seven studies in ulcerative colitis (UC). In CD, there was a trend to superiority of PCE over MRE and colonoscopy with a pooled odds ratio (OR) of 1.25 (95% CI, 0.85-1.86%) for the detection of CD. This translates to an increased diagnostic yield of 5% and 7% for PCE compared with MRE and colonoscopy, respectively. PCEs had a diagnostic sensitivity for the detection of UC of 93.8% (95% CI, 87.6-97.0%) and a specificity of 69.8% (95% CI, 38.2-89.6%).

CONCLUSION

PCEs have a comparable diagnostic yield to colonoscopy and MRE in Crohn's disease. The major difficulty remains standardization of PCE scoring systems and the lack of transmural assessment. In UC, PCE has an excellent diagnostic sensitivity and positive predictive value, but there are limitations to its use including the lack of histologic assessment and poor specificity.

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.

Assessment of endoscopic response using pan-enteric capsule endoscopy in Crohn's disease; the Sensitivity to Change (STOC) study

BACKGROUND

The potential use of pan-enteric capsule endoscopy (pan-CE) to evaluate mucosal changes during treatment has not been evaluated. We aimed to assess the ability of pan-CE to measure changes in mucosal disease activity before and after starting biologic treatment in Crohn's disease patients.

METHODS

In this two-center prospective study, patients with clinical and biochemical signs of active Crohn's disease underwent pan-CE before and 8 to 12 weeks after treatment initiation with infliximab, adalimumab or vedolizumab. Endoscopic disease activity was assessed using the simple endoscopic score for Crohn's disease (SES-CD) and the Crohn's disease endoscopic index of severity (CDEIS), expanded with two segments (i.e., the jejunum and pre-terminal ileum). Occurrence of endoscopic remission (i.e., absence of ulcers) and endoscopic response (i.e., 50% decrease in SES-CD and CDEIS scores compared to baseline) was assessed and the standardized effect size was calculated.

RESULTS

Twenty-two patients (50% females) completed the study. Endoscopic remission was observed in 6 out of 22 (27%) patients and 13/22 patients (59%) showed an endoscopic response for both the SES-CD and CDEIS score. Median SES-CD and CDEIS scores decreased from 16.0 (IQR 10.0 - 24.0) to 6.0 (IQR 2.8 - 12.0, p = .001) and from 7.1 (IQR 4.6 - 11.2) to 3.0 (IQR 0.9 - 6.0, p = .001), respectively. The standardized effect size was 1.44 and 1.24 for the SES-CD and CDEIS, respectively. No adverse events related to pan-CE were reported.

CONCLUSION

Pan-CE was a useful technique to assess changes in mucosal disease activity in Crohn's disease patients.

Review: Colon Capsule Endoscopy in Inflammatory Bowel Disease

The COVID-19 pandemic has caused considerable disruption in healthcare services and has had a substantial impact on the care of patients with chronic diseases, such as inflammatory bowel disease. Endoscopy services were significantly restricted, resulting in long waiting lists. There has been a growing interest in the use of capsule endoscopy in the diagnostic pathway and management of these patients. This review explores the published literature on the role of colon capsule endoscopy in ulcerative colitis and Crohn’s disease as a method for mucosal assessment of extent, severity, and response to treatment. Colon capsule preparation regimens and scoring systems are reported. The studies indicate that, despite inherent limitations of minimally invasive capsule endoscopy, there is increasing evidence to support the use of the second-generation colon capsule in inflammatory bowel disease evaluation, providing an additional pathway to expedite investigation of appropriate patients especially during and after the pandemic.

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.

Small Bowel Volvulus as Delayed Presentation of Undiagnosed Crohn's Disease: A Case Report

Introduction

Emergency department (ED) visits related to flare-ups of inflammatory bowel disease (IBD) are becoming more prevalent. There are many potentially dangerous complications and sequelae of uncontrolled IBD.

Case Report

We report a case of a middle-aged woman who presented with a few hours of severe abdominal pain, nausea, and vomiting. Given her hemodynamic instability, she was sent urgently for computed tomography, which showed an incomplete small bowel malrotation, mesenteric volvulus, and high-grade small bowel obstruction with evolving ischemia. The patient underwent exploratory laparotomy to resect most of her small intestines. Biopsies later revealed active Crohn’s disease.

Conclusion

Patients with flare-ups of IBD are common in the ED, but very few present with a midgut volvulus later in life. Our case is unique and adds to the literature due to the dramatic consequences of undiagnosed Crohn’s disease in a patient with intermittent symptoms and extensive workup spanning over two decades.

Capsule Endoscopy in Crohn's Disease-From a Relative Contraindication to Habitual Monitoring Tool

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

Examination of Entire Gastrointestinal Tract: A Perspective of Mouth to Anus (M2A) Capsule Endoscopy

Capsule endoscopy (CE) is the only non-invasive diagnostic tool that enables the direct visualization of the gastrointestinal (GI) tract. Even though CE was initially developed for small-bowel investigation, its clinical application is expanding, and technological advances continue. The final iteration of CE will be a mouth to anus (M2A) capsule that investigates the entire GI tract by the ingestion of a single capsule. This narrative review describes the current developmental status of CE and discusses the possibility of realizing an M2A capsule and what needs to be overcome in the future.

Clinical feasibility of panintestinal (or panenteric) capsule endoscopy: a systematic review

In recent years, panintestinal capsule endoscopy (PCE) with double-headed capsules has been used to perform complete, single-sitting exploration of both small bowel and colon in different clinical conditions. Double-headed capsules for colonic examination (CCE) have been exploited first in this setting, followed by newer generations of capsules (i.e. PillCam Crohn, PCC) specifically engineered for this purpose. The aim of this study was to evaluate the feasibility of PCE in the form of a systematic review. We performed a comprehensive literature search to identify papers in which CE was specifically used for a PCE of the gastrointestinal tract. Data on CE, bowel preparation regimen, rate of cleanliness and completeness, and data on transit times were analyzed. The primary outcome was to assess the feasibility of a whole-gut exploration with CE. Sixteen (n = 16) studies including 915 CE procedures with CCE1 (n = 134), CCE2 (n = 357) and PCC (n = 424) were included. 13/16 studies were performed in the setting of Crohn's disease. Cleanliness and completeness rates were acceptable in all studies, ranging from 63.9% and 68.6% to 100%, respectively. In conclusion, PCE is a feasible technique, although further structured studies are needed to explore its full potential.