Applicability of colon capsule endoscopy as pan-endoscopy: From bowel preparation, transit, and rating times to completion rate and patient acceptance

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.

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.

What Is the Optimal Bowel Preparation for Capsule Colonoscopy and Pan-intestinal Capsule Endoscopy? A Systematic Review and Meta-Analysis

BACKGROUND

The rate of adequate cleansing (ACR) and complete examinations (CR) are key quality indicators in capsule colonoscopy (CC) and pan-intestinal capsule endoscopy (PCE).

AIMS

To evaluate the efficacy of bowel preparation protocols regarding ACR and CR.

METHODS

We conducted a systematic review and meta-analysis, search terms regarding colon capsule preparation, publication date from 2006/01, and date of search 2021/12, in six bibliographic databases. Multiple steps of the cleansing protocol were assessed: diet, adjunctive laxatives, purgative solution, use of prokinetic agents, and "booster". The meta-analytical frequency of ACR and CR was estimated, and subgroup analyses performed. Strategies associated with higher ACR and CR were explored using meta-analytical univariable and multivariable regression models.

RESULTS

Twenty-six observational studies and five RCTs included (n = 4072 patients). The pooled rate of ACR was 72.5% (95% C.I. 67.8-77.5%; I2 = 92.4%), and the pooled rate of CR was 83.0% (95% C.I. 78.7-87.7%; I2 = 96.5%). The highest ACR were obtained using a low-fibre diet [78.5% (95% C.I. 72.0-85.6%); I2 = 57.0%], adjunctive laxatives [74.7% (95% C.I. 69.8-80.1%); I2 = 85.3%], and split dose < 4L polyethylene glycol (PEG) as purgative [77.5% (95% C.I. 68.4-87.8%); I2 = 47.3%]. The highest CR were observed using routine prokinetics prior to capsule ingestion [84.4% (95% C.I. 79.9-89.2%); I2 = 89.8%], and sodium phosphate (NaP) as "booster" [86.2% (95% C.I. 82.3-90.2%); I2 = 86.8%]. In univariable models, adjunctive laxatives were associated with higher ACR [OR 1.81 (95% C.I. 1.13; 2.90); p = 0.014]. CR was higher with routine prokinetics [OR 1.86 (95% C.I. 1.13; 3.05); p = 0.015] and split-dose PEG purgative [OR 2.03 (95% C.I. 1.01; 4.09), p = 0.048].

CONCLUSIONS

Main quality outcomes (ACR, CR) remain suboptimal for CC and PCE. Despite considerable heterogeneity, our results support low-fibre diet, use of adjunctive sennosides, split dose < 4L PEG, and routine prokinetics, while NaP remains the most consistent option as booster.

Small Bowel CLEansing Assessment and Report (SB-CLEAR): Standardizing bowel preparation report in capsule endoscopy

BACKGROUND AND AIM

Small-bowel (SB) cleansing is crucial to assess the reliability of capsule endoscopy (CE) findings. However, the presence of multiple grading systems is hampering their use in clinical practice. In 2020, Colon CLeansing Assessment and Report (CC-CLEAR) was created and validated. We sought to develop and validate a new score for the evaluation of the SB cleansing, adapted from CC-CLEAR, aiming to standardize CE reporting regarding the quality of preparation.

METHODS

The new grading score, SB CLeansing Assessment and Report (SB-CLEAR), divided the SB into three tertiles, each being scored depending on the percentage of visualized mucosa (0, < 50%; 1, 50%-75%; 2, > 75%; 3, > 90%). The overall classification was a sum of each segment score, graded between excellent, good, and inadequate (0-5). Any segment scoring ≤1 resulted in inadequate overall classification. CE videos were prospectively evaluated by two experienced CE readers blinded to each other.

RESULTS

We included 52 CEs, 41(78.8%) female, with a mean age of 57.9 ± 17.9 years. Inter-observer agreement was very strong for each tertile (first: r = 0.863; second: r = 0.865; third: r = 0.861; P < 0.001), which resulted in overall excellent correlation when considering the quality of preparation in all tertiles (r = 0.940; P < 0.001). By applying final classifications of "inadequate," "good," and "excellent," correlation between observers was also very strong (r = 0.875; P < 0.001).

CONCLUSIONS

SB-CLEAR is an innovative and reproducible grading score for evaluation of SB preparation quality in CE, with overall excellent inter-observer agreement. Along with CC-CLEAR, this may become a valuable tool to uniformize reporting of bowel preparation quality in CE.

The Effectiveness of a Very Low-Volume Compared to High-Volume Laxative in Colon Capsule Endoscopy

Colon capsule endoscopy (CCE) is a promising modality for colonic investigations, but completion rates (CR) and adequate cleansing rates (ACR) must be improved to meet established standards for optical colonoscopy. Improvements should be made with patient acceptability in mind. We aimed to compare a very low-volume polyethylene glycol (PEG) laxative to a conventional high-volume laxative. We carried out a single-center retrospective comparative cohort study including patients referred for CCE. One hundred and sixty-six patients were included in the final analysis, with eighty-three patients in each group. We found a CR and ACR of 77% and 67% in the high-volume group and 72% and 75% in the very low-volume group, respectively. In the high-volume group, 54% had complete transit and adequate cleansing, whereas this was the case for 63% in the very low-volume group. No statistically significant difference in CR, ACR, or a combination of the two was found. A very low-volume bowel preparation regimen was non-inferior to a high-volume regimen before CCE in terms of CR and ACR.

Artificial Intelligence in Colon Capsule Endoscopy—A Systematic Review

Background and aims: The applicability of colon capsule endoscopy in daily practice is limited by the accompanying labor-intensive reviewing time and the risk of inter-observer variability. Automated reviewing of colon capsule endoscopy images using artificial intelligence could be timesaving while providing an objective and reproducible outcome. This systematic review aims to provide an overview of the available literature on artificial intelligence for reviewing colonic mucosa by colon capsule endoscopy and to assess the necessary action points for its use in clinical practice. Methods: A systematic literature search of literature published up to January 2022 was conducted using Embase, Web of Science, OVID MEDLINE and Cochrane CENTRAL. Studies reporting on the use of artificial intelligence to review second-generation colon capsule endoscopy colonic images were included. Results: 1017 studies were evaluated for eligibility, of which nine were included. Two studies reported on computed bowel cleansing assessment, five studies reported on computed polyp or colorectal neoplasia detection and two studies reported on other implications. Overall, the sensitivity of the proposed artificial intelligence models were 86.5–95.5% for bowel cleansing and 47.4–98.1% for the detection of polyps and colorectal neoplasia. Two studies performed per-lesion analysis, in addition to per-frame analysis, which improved the sensitivity of polyp or colorectal neoplasia detection to 81.3–98.1%. By applying a convolutional neural network, the highest sensitivity of 98.1% for polyp detection was found. Conclusion: The use of artificial intelligence for reviewing second-generation colon capsule endoscopy images is promising. The highest sensitivity of 98.1% for polyp detection was achieved by deep learning with a convolutional neural network. Convolutional neural network algorithms should be optimized and tested with more data, possibly requiring the set-up of a large international colon capsule endoscopy database. Finally, the accuracy of the optimized convolutional neural network models need to be confirmed in a prospective setting.

Obscure Gastrointestinal Bleeding and Capsule Endoscopy: A Win-Win Situation or Not?

Obscure gastrointestinal bleeding (OGIB) refers to bleeding of uncertain origin that persists or recurs after negative workup using any of the radiologic evaluation modalities. It can be divided into two types based on whether clinically evident bleeding is present, namely, obscure overt and obscure occult bleeding. As the visualization of the bowel mucosa is challenging, capsule endoscopy (CE) is the ideal go-to procedure as the process is wireless, ingestible, small, disposable, and, most importantly, non-invasive. This review article has compiled various studies to shed light on the guidelines for using CE, its structure and procedure, patient preferences, diagnostic yield, cost-effectiveness, and the future. The goal of this review is to show the influence of CE on OGIB on the aspects mentioned earlier.