Use of the Endocuff during routine colonoscopy examination improves adenoma detection: A meta-analysis

Use of artificial intelligence improves colonoscopy performance in adenoma detection: a systematic review and meta-analysis

BACKGROUND AND AIMS

Artificial intelligence (AI) is increasingly used to improve adenoma detection during colonoscopy. This meta-analysis aimed to provide an updated evaluation of computer-aided detection (CADe) systems and their impact on key colonoscopy quality indicators.

METHODS

We searched the EMBASE, PubMed, and MEDLINE databases from inception until February 15, 2024, for randomized control trials (RCTs) comparing the performance of CADe systems with routine unassisted colonoscopy in the detection of colorectal adenomas.

RESULTS

Twenty-eight RCTs were selected for inclusion involving 23,861 participants. Random-effects meta-analysis demonstrated a 20% increase in adenoma detection rate (risk ratio [RR], 1.20; 95% confidence interval [CI], 1.14-1.27; P < .01) and 55% decrease in adenoma miss rate (RR, 0.45; 95% CI, 0.37-0.54; P < .01) with AI-assisted colonoscopy. Subgroup analyses involving only expert endoscopists demonstrated a similar effect size (RR, 1.19; 95% CI, 1.11-1.27; P < .001), with similar findings seen in analysis of differing CADe systems and healthcare settings. CADe use also significantly increased adenomas per colonoscopy (weighted mean difference, 0.21; 95% CI, 0.14-0.29; P < .01), primarily because of increased diminutive lesion detection, with no significant difference seen in detection of advanced adenomas. Sessile serrated lesion detection (RR, 1.10; 95% CI, 0.93-1.30; P = .27) and miss rates (RR, 0.44; 95% CI, 0.16-1.19; P = .11) were similar. There was an average 0.15-minute prolongation of withdrawal time with AI-assisted colonoscopy (weighted mean difference, 0.15; 95% CI, 0.04-0.25; P = .01) and a 39% increase in the rate of non-neoplastic resection (RR, 1.39; 95% CI, 1.23-1.57; P < .001).

CONCLUSIONS

AI-assisted colonoscopy significantly improved adenoma detection but not sessile serrated lesion detection irrespective of endoscopist experience, system type, or healthcare setting.

Comparison of adenoma miss rate and adenoma detection rate between conventional colonoscopy and colonoscopy with second-generation distal attachment cuff: a multicenter, randomized, back-to-back trial

BACKGROUND AND AIMS

Endocuff Vision (Olympus Europe, Hamburg, Germany) has been designed to enhance mucosal visualization, thereby improving detection of (pre-)malignant colorectal lesions. This multicenter, international, back-to-back, randomized colonoscopy trial compared the adenoma detection rate (ADR) and adenoma miss rate (AMR) between Endocuff Vision-assisted colonoscopy (EVC) and conventional colonoscopy (CC).

METHODS

Patients aged 40 to 75 years referred for non-immunochemical fecal occult blood test-based screening, surveillance, or diagnostic colonoscopy were included at 10 hospitals and randomized into 4 groups: group 1, 2 × CC; group 2, CC followed by EVC; group 3, EVC followed by CC; and group 4, 2 × EVC. Primary outcomes included ADR and AMR.

RESULTS

A total of 717 patients were randomized, of whom 661 patients (92.2%) had 1 and 646 (90.1%) patients had 2 completed back-to-back colonoscopies. EVC did not significantly improve ADR compared to CC (41.1%; [95% confidence interval (CI), 36.1-46.3] vs 35.5% [95% CI, 30.7-40.6], respectively; P = .125), but EVC did reduce AMR by 11.7% (29.6% [95% CI, 23.6-36.5] vs 17.9% [95% CI, 12.5-23.5], respectively; P = .049). AMR of 2 × CC compared to 2 × EVC was also not significantly different (25.9% [95% CI, 19.3-33.9] vs 18.8% [95% CI, 13.9-24.8], respectively; P = .172). Only 3.7% of the polyps missed during the first procedures had advanced pathologic features. Factors affecting risk of missing adenomas were age (P = .002), Boston Bowel Preparation Scale (P = .008), and region where colonoscopy was performed (P < .001).

CONCLUSIONS

Our trial shows that EVC reduces the risk of missing adenomas but does not lead to a significantly improved ADR. Remarkably, 25% of adenomas are still missed during conventional colonoscopies, which is not different from miss rates reported 25 years ago; reassuringly, advanced features were only found in 3.7% of these missed lesions. (Clinical trial registration number: NCT03418948.).

Optimizing adenoma detection in screening-related colonoscopy

INTRODUCTION

Screening-related colonoscopy is a vital component of screening initiatives to both diagnose and prevent colorectal cancer (CRC), with prevention being reliant upon early and accurate detection of pre-malignant lesions. Several strategies, techniques, and interventions exist to optimize endoscopists' adenoma detection rates (ADR).

AREAS COVERED

This narrative review provides an overview of the importance of ADR and other colonoscopy quality indicators. It then summarizes the available evidence regarding the effectiveness of the following domains in terms of improving ADR: endoscopist factors, pre-procedural parameters, peri-procedural parameters, intra-procedural strategies and techniques, antispasmodics, distal attachment devices, enhanced colonoscopy technologies, enhanced optics, and artificial intelligence. These summaries are based on an electronic search of the databases Embase, Pubmed, and Cochrane performed on December 12, 2022.

EXPERT OPINION

Given the prevalence and associated morbidity and mortality of CRC, the quality of screening-related colonoscopy quality is appropriately prioritized by patients, endoscopists, units, and payers alike. Endoscopists performing colonoscopy should be up to date regarding available strategies, techniques, and interventions to optimize their performance.

The Role of an Artificial Intelligence Method of Improving the Diagnosis of Neoplasms by Colonoscopy

BACKGROUND

Colorectal cancer (CRC) is the third most common cancer worldwide. Colonoscopy is the gold standard examination that reduces the morbidity and mortality of CRC. Artificial intelligence (AI) could be useful in reducing the errors of the specialist and in drawing attention to the suspicious area.

METHODS

A prospective single-center randomized controlled study was conducted in an outpatient endoscopy unit with the aim of evaluating the usefulness of AI-assisted colonoscopy in PDR and ADR during the day time. It is important to understand how already available CADe systems improve the detection of polyps and adenomas in order to make a decision about their routine use in practice. In the period from October 2021 to February 2022, 400 examinations (patients) were included in the study. One hundred and ninety-four patients were examined using the ENDO-AID CADe artificial intelligence device (study group), and 206 patients were examined without the artificial intelligence (control group).

RESULTS

None of the analyzed indicators (PDR and ADR during morning and afternoon colonoscopies) showed differences between the study and control groups. There was an increase in PDR during afternoon colonoscopies, as well as ADR during morning and afternoon colonoscopies.

CONCLUSIONS

Based on our results, the use of AI systems in colonoscopies is recommended, especially in circumstances of an increase of examinations. Additional studies with larger groups of patients at night are needed to confirm the already available data.

Endocuff-assisted versus standard colonoscopy for improving adenoma detection rate: meta-analysis of randomized controlled trials

BACKGROUND

The effect of Endocuff-assisted colonoscopy compared with standard colonoscopy is conflicting in terms of the adenoma detection rate. The aim of this meta-analysis was to compare the efficacy of Endocuff-assisted colonoscopy for adenoma detection.

METHODS

PubMed, Embase, Google Scholar and Cochrane Library were searched up to the end of June 8, 2021. All randomized controlled trials (RCTs) comparing Endocuff-assisted colonoscopy with standard colonoscopy were included. Dichotomous data were pooled to obtain the relative risk with a 95% CI, whereas continuous data were pooled using a mean difference with 95% CI.

RESULTS

A total of 23 RCTs involving 17,999 patients were included. Compared with standard colonoscopy, use of the Endocuff was associated with a significant improvement in the adenoma detection rate (RR = 1.16, 95% CI 1.08-1.24), polyp detection rate (RR = 1.17, 95% CI 1.09-1.25), sessile serrated lesion detection rate (RR = 1.23, 95% CI 1.05-1.43), left-side lesion detection rate (RR = 1.24, 95% CI 1.08-1.43), and mean number of adenomas per patient (MD = 0.17, 95% CI 0.08-0.26). There were no significant differences between the and groups in detection of advanced adenomas, mean number of polyps per patient, right-side lesion detection rate, cecal intubation rate, cecal intubation time and withdrawal time.

CONCLUSIONS

The pooled evidence suggests a significant improvement in the adenoma detection rate, and polyp detection rate using the Endocuff. On the other hand, no significant effect on the detection of advanced adenomas and mean number of polyps per patient was noted.

Second-generation distal attachment cuff for adenoma detection in screening colonoscopy: a randomized multicenter study

BACKGROUND AND AIMS

Randomized studies have demonstrated that a distal attachment cap with rubber side arms, the Endocuff Vision (ECV; Olympus America, Center Valley, Pa, USA), increased colonoscopic adenoma detection rate (ADR) in various mixed patient collectives. This is the first study to evaluate its use in a primary colonoscopic screening program.

METHODS

Patients over age 55 years undergoing screening colonoscopy in 9 German private offices in Berlin and Hamburg were randomized to either the study group using ECV or the control group using high-definition colonoscopies (standard of care). The main outcome parameter was ADR, whereas secondary outcomes were detection rates of all adenomas per colonoscopy (APCs), of adenoma subgroups, and of hyperplastic polyps.

RESULTS

Of 1416 patients (mean age, 61.1 years; 51.8% women), with a median of 41 examinations per examiner (n = 23; interquartile range, 12-81), 700 were examined with ECV and 716 without. Adjusting for the effects of the colonoscopies, ADR was 39.5% (95% confidence interval [CI], 32.6%-46.3%) in the ECV group versus 32.2% (95% CI, 25.9%-38.6%) in the control group, which resulted in an increase of 7.2% (95% CI, 2.3%-12.2%; P = .004). The increase in ADR was mainly because of small polyps, with adjusted ADRs for adenomas <10 mm of 33.3% (95% CI, 26.5%-40.2%) for study patients versus 24.0% (95% CI, 18.2%-29.8%) for control patients (P < .001). APC was also significantly increased (.57 ECV vs .51 control subjects, P = .045).

CONCLUSIONS

A distal attachment cap with side arms significantly increased the ADR in patients undergoing primary colonoscopic screening. Because of the correlation of ADR and interval cancer, its use should be encouraged, especially in this setting. (Clinical trial registration number: NCT03442738.).

The effect of the endoscopic device Endocuff™/Endocuff vision™ on quality standards in colonoscopy: A systematic review and meta-analysis of randomized trials

AIM

The adenoma detection rate (ADR) is an important quality measure, with a high ADR reflecting high-quality colonoscopy. This systematic review and meta-analysis aimed to assess the effects of Endocuff™/Endocuff Vision™-assisted colonoscopy (EAC) versus standard colonoscopy (SC) on ADR and other clinical, patient and resource-use outcomes.

METHOD

MEDLINE, EMBASE, Web of Science, Scopus and the Cochrane Central Register of Controlled Trials were searched for full papers reporting randomized studies comparing EAC with SC. The primary outcome was ADR. Secondary outcomes comprised key polyp/adenoma detection, procedure-related, patient-related and health economic measures. Random effects meta-analyses provided pooled estimates of outcomes [risk ratio (RR) or mean difference (MD), with 95% confidence intervals (CI)].

RESULTS

Twelve parallel-group randomized controlled trials (RCTs) and three crossover RCTs with data on 9140 patients were included. EAC significantly increased the ADR (RR 1.18, 95% CI 1.09-1.29), mean adenomas per procedure (MAP) (MD 0.19, 95% CI 0.06-0.33), polyp detection rate (PDR) (RR 1.20, 95% CI 1.10-1.30) and mean polyps per procedure (MPP) (MD 0.39, 95% CI 0.14-0.63) versus SC. EAC significantly increased segmental PDR versus SC in the sigmoid (RR 2.02, 95% CI 1.64-2.49), transverse (RR 1.63, 95% CI 1.09-2.42), ascending (RR 1.74, 95% CI 1.26-2.41) and caecal segments (RR 1.91, 95% CI 1.29-2.82). Procedure-related variables did not differ between arms. There were insufficient data for meta-analysis of health economic or patient-centred outcomes.

CONCLUSIONS

EAC increased ADR, MAP, PDR and MPP versus SC without detrimental effects on procedure measures. Cost-effectiveness and patient experience data are lacking and would be valuable to inform practice recommendations.

Endocuff-assisted push enteroscopy increases the detection of proximal small-bowel gastrointestinal angiodysplasias

Gastrointestinal angiodysplasias (GIADs) are the most common causes for suspected small bowel bleeding. Fifty percent of GIADs do not need treatment due to bleeding cessation, while 45% have high re-bleeding rates, that significantly impact patient outcome and health resource utilization. We suspected that this high re-bleeding rate occurs because not all lesions are detected with present standard of care. This study evaluates whether device-assisted enteroscopy (DAE) utilizing the Endocuff (EC) device could improve GIAD detection. A retrospective chart review of a prospective data collection was performed from January 2006 to December 2018 at VA Loma Linda Healthcare System (VALLHCS) on both inpatients and outpatients referred for active and chronic suspected small bowel bleeding. The patients were initially monitored for bleeding lesions via video capsule endoscopy (VCE) after negative upper and lower endoscopy. GIADs observed between 0% to 40% small bowel transit time (SBTT) were referred for push enteroscopy (PE) with and without (±) the EC device. Twenty-five consecutive patients underwent PE ± EC. No patient had VCE done after PE ± EC. Using PE-EC, GIADs were detected in 9 of 25 (36%) of patients. Importantly, PE+EC detected GIADs in 23 of 25 (92%) patients. The sum of GIADs detected without EC was 26 ± 0.06 vs. 112 ± 0.2 using EC. The average detection rate for PE without EC was significantly lower (1.04 ± 0.06, mean ± SE) as compared to PE with EC (4.48 ± 0.23, mean ± SE, p<0.0005). Additionally, a positive correlation (r=0.51) between capsule enteroscopy (CE) location of GIADs and SBTT was found. The EC device increases the detection of GIADs in the proximal small bowel. We also reconfirm that the location of bleeding GIADs are within the reach of the push enteroscope (PE). Finally, PE + EC may also reduce GIAD miss rates, which may play a role in the reduction of re-bleeding episodes.

Clinical evaluation of a real-time artificial intelligence-based polyp detection system: a US multi-center pilot study

Artificial intelligence (AI) has increasingly been employed in multiple fields, and there has been significant interest in its use within gastrointestinal endoscopy. Computer-aided detection (CAD) can potentially improve polyp detection rates and decrease miss rates in colonoscopy. However, few clinical studies have evaluated real-time CAD during colonoscopy. In this study, we analyze the efficacy of a novel real-time CAD system during colonoscopy. This was a single-arm prospective study of patients undergoing colonoscopy with a real-time CAD system. This AI-based system had previously been trained using manually labeled colonoscopy videos to help detect neoplastic polyps (adenomas and serrated polyps). In this pilot study, 300 patients at two centers underwent elective colonoscopy with the CAD system. These results were compared to 300 historical controls consisting of consecutive colonoscopies performed by the participating endoscopists within 12 months prior to onset of the study without the aid of CAD. The primary outcome was the mean number of adenomas per colonoscopy. Use of real-time CAD trended towards increased adenoma detection (1.35 vs 1.07, p = 0.099) per colonoscopy though this did not achieve statistical significance. Compared to historical controls, use of CAD demonstrated a trend towards increased identification of serrated polyps (0.15 vs 0.07) and all neoplastic (adenomatous and serrated) polyps (1.50 vs 1.14) per procedure. There were significantly more non-neoplastic polyps detected with CAD (1.08 vs 0.57, p < 0.0001). There was no difference in ≥ 10 mm polyps identified between the two groups. A real-time CAD system can increase detection of adenomas and serrated polyps during colonoscopy in comparison to historical controls without CAD, though this was not statistically significant. As this pilot study is underpowered, given the findings we recommend pursuing a larger randomized controlled trial to further evaluate the benefits of CAD.

Endo-wing versus transparent hood-assisted colonoscopy for colorectal adenoma detection: A randomized controlled trial

BACKGROUND AND AIM

This study aimed to compare the mean number of adenomas in patients undergoing Endo-wing-assisted colonoscopy (EAC) and transparent hood-assisted colonoscopy (TAC).

METHODS

Patients undergoing colonoscopy for positive fecal immunochemical tests, colon polyp surveillance, and evaluation of abdominal symptoms at a single institution were randomly assigned to the EAC or TAC group. The mean number of adenomas per patient, adenoma detection rate, cecal intubation time, withdrawal time, mean number of adenomas per location, and adenoma size were compared.

RESULTS

Overall, 800 patients were enrolled. The EAC and TAC groups comprised 372 and 393 patients, respectively. The groups did not significantly differ with respect to cecal intubation and withdrawal times. The mean number of adenomas per patient was significantly higher in the EAC group (1.13 vs 0.90, P = 0.04), particularly in the sigmoid colon (0.54 [201/372] vs 0.38 [149/393], P = 0.04). The adenoma detection rates were 48.1% and 45.0% in the EAC and TAC groups, respectively, albeit without significant difference between the two groups (P = 0.393). The total number of sessile-type adenomas (0.73 [270/372] vs 0.47 [183/393], P < 0.0001) and small polyps (≤ 5 mm) (0.53 [198/372] vs 0.41 [159/393], P = 0.016) was significantly higher in the EAC group.

CONCLUSION

Endo-wing-assisted colonoscopy is significantly superior to TAC in terms of the mean number of adenomas per patient.

Measuring and Improving Quality of Colonoscopy for Colorectal Cancer Screening

Colorectal cancer (CRC) is largely preventable, yet it remains a major public health issue as it is the third most common and deadly malignancy in the United States. While there are many ways to screen for CRC, colonoscopy remains the gold standard as it is the only test that is both cancer-detecting and cancer-preventing through removal of precancerous polyps. Through identifying and removing neoplastic lesions, colonoscopy reduces CRC incidence by 31%-91% and CRC mortality by 65%-88%. However, colonoscopy is not an infallible test-there is a chance for missed lesions during the exam and there is substantial variation in outcomes among endoscopists. To enhance the quality of colonoscopic exams, and ultimately to improve CRC outcomes, quality indicators have been developed for measuring endoscopists' performance. In this review, we describe the colonoscopic quality indicators and benchmarks recommended by the American Society for Gastrointestinal Endoscopy/American College of Gastroenterology Task Force on Quality in Endoscopy for screening colonoscopies in average-risk individuals. Measuring and monitoring endoscopists' performance on these measures are critical first steps in striving toward conducting high quality exams. We also review the evidence for interventions that aim to improve critical measures including adenoma detection rate, withdrawal time, cecal intubation, and bowel preparation quality. Finally, we provide a preview of the forthcoming Advancing Care for Appropriate Colon Health Merit-Based Incentive Payment System Value Pathway by the Centers for Medicare & Medicaid Services and its potential impact on clinical practice.

Endocuff Vision improves adenoma detection rate in a large screening-related cohort

Background and study aims  Endocuff Vision (ECV) increases adenoma detection rate (ADR) in randomized clinical trials; however, observational effectiveness data are lacking. We evaluated the effectiveness, safety, and practical aspects of ECV use in a large screening-related real-world cohort. Patients and methods  In this observational study, patients undergoing screening-related colonoscopy from November 2018 to April 2019 comprised the baseline period, and those undergoing it from June to November 2019 comprised the ECV period, where ECV use was discretionary. The primary outcome was ADR, compared: 1) between ECV use and standard colonoscopy across both periods; and 2) between time periods. Secondary outcomes included indication-specific ADR, sessile serrated ADR (SSADR), cecal intubation rate (CIR), procedure times, patient comfort scores, and sedation use. Multilevel logistic regression was performed, yielding adjusted odds ratios (AOR) with 95 % confidence intervals (CIs). Results  In 15,814 colonoscopies across both time periods, ADR was 46.7 % with standard colonoscopy and 54.6 % when ECV was used ( P  < 0.001). Endoscopists used ECV in 77.6 % of procedures in the ECV period, during which overall ADR rose to 53.2 % compared to 46.3 % in the baseline period ( P  < 0.001). ECV use was significantly associated with higher ADR (AOR 1.24, 95 % CI 1.10 to 1.40) after adjusting for relevant covariates including time period. ECV use did not result in lower CIR, longer procedure time, increased sedation use, or poorer comfort scores. Conclusions  ECV use is associated with improved ADR without negatively impacting other key procedure and patient-related factors. Future studies should evaluate the cost-effectiveness of incorporating ECV into routine screening-related practice.

Linked color imaging versus white light imaging colonoscopy for colorectal adenoma detection: A randomized controlled trial

BACKGROUND AND AIM

The adenoma detection rate is an important indicator of colonoscopy quality and colorectal cancer incidence. We compared the adenoma detection rates between white light imaging (WLI) and linked color imaging (LCI) colonoscopy.

METHODS

Patients undergoing colonoscopy for positive fecal immunochemical tests, follow-up of colon polyps, and abdominal symptoms at three institutions were randomly assigned to the LCI or WLI groups. Mean adenoma number per patient (including based on endoscopists' experience), adenoma detection rate, cecal intubation time, withdrawal time, mean adenoma number per location, and adenoma size were compared.

RESULTS

The LCI and WLI groups comprised 494 and 501 patients, respectively. No significant differences in the cecal intubation rate (LCI vs WLI: 99.5% vs 99.4%), cecal intubation time, and withdrawal time were noted between groups. The mean adenoma number per patient was significantly higher in the LCI group than in the WLI group (1.07 vs 0.88, P = 0.04), particularly in the descending [0.12 (58/494) vs 0.07 (35/501), P = 0.01] and sigmoid colon [0.41 (201/494) vs 0.30 (149/501), P ≤ 0.001]. However, the adenoma detection rate was 47.1% in the LCI group and 46.9% in the WLI group, with no significant difference (P = 0.93). The total number of sessile-type adenomas was significantly higher in the LCI group than in the WLI group (346/494 vs 278/501, P = 0.04). As for polyp size, small polyps (≤ 5 mm) were detected at a significantly higher rate in the LCI group (271/494 vs 336/501, P = 0.04).

CONCLUSION

Linked color imaging is significantly superior to WLI in terms of mean adenoma number per patient.

Second-generation distal attachment cuff improves adenoma detection rate: meta-analysis of randomized controlled trials

BACKGROUND AND AIMS

Multiple randomized controlled trials (RCTs) using the second-generation distal attachment cuff device (Endocuff Vision; Olympus America, Center Valley, Pa, USA) have reported conflicting results in improving adenoma detection rate (ADR) compared with standard high-definition colonoscopy without the distal attachment. We conducted a systematic review and meta-analysis of RCTs to compare outcomes between second-generation cuff colonoscopy (CC) versus colonoscopy without the distal attachment (standard colonoscopy [SC]).

METHODS

An electronic literature search was performed using PubMed, Google Scholar, Embase, and Cochrane Library through May 2020. The primary outcome was reporting of ADR, and secondary outcomes were polyp detection rate (PDR), mean withdrawal time, mean adenomas per colonoscopy (APC), sessile serrated lesion detection rate, and adverse events. Pooled rates and risk ratios (RRs) with 95% confidence intervals were reported.

RESULTS

Eight RCTs with 5695 patients were included in the final analysis, with 2862 patients (mean age, 62.8 years; 52.9% men) in the CC group and 2833 patients (mean age, 62.6 years; 54.2% men) in the SC group. Compared with SC, use of CC was associated with a significant improvement in ADR (49.8% vs 45.6%, respectively; RR, 1.12; P = .02), PDR (58.1% vs 53%, respectively; RR, 1.12; P = .009), and APC (P < .01). Furthermore, use of CC had a .93-minute lower mean withdrawal time (P < .01) when compared with SC. The difference in ADR was larger in the screening/surveillance population (6.5%, P = .02) and when used by endoscopists with ADRs <30% (9.4%, P = .03).

CONCLUSIONS

The results of this meta-analysis of randomized trials show a significant improvement in ADR and APC with shorter withdrawal times using the second-generation cuff device compared with SC.

Efficacy of Endocuff Vision compared to first-generation Endocuff in adenoma detection rate and polyp detection rate in high-definition colonoscopy: a systematic review and network meta-analysis

Background and study aims  Recently, the newer Endocuff Vision (ECV) has been evaluated for improving colonoscopy outcome metrics such as adenoma detection rate (ADR) and polyp detection rate (PDR). Due to lack of direct comparative studies between ECV and original Endocuff (ECU), we performed a systematic review and network meta-analysis to evaluate these outcomes. Methods  The following databases were searched: PubMed, Embase, Cochrane, and Web of Sciences to include randomized controlled trials (RCTs) comparing ECV or ECU colonoscopy to high-definition (HD) colonoscopy. Direct as well as network meta-analyses comparing ADR and PDR were performed using a random effects model. Relative-risk (RR) with 95 % confidence interval (CI) was calculated. Results  A total of 12 RCTs with 8638 patients were included in the final analysis. On direct meta-analysis, ECV did not demonstrate statistically improved ADR compared to HD colonoscopy (RR: 1.12, 95 % CI 0.99-1.27). A clinically and statistically improved PDR was noted for ECV compared to HD (RR: 1.15, 95 % CI 1.03-1.28) and ECU compared to HD (RR: 1.26, 95 % CI 1.09-1.46) as well as improved ADR (RR: 1.22, 95 % CI 1.05-1.43) was observed for ECU colonoscopy when compared to HD colonoscopy. These results were also consistent on network meta-analysis. Lower overall complication rates (RR: 0.14, 95 % CI 0.02-0.84) and particularly lacerations/erosions (RR: 0.11, 95 % CI 0.02-0.70) were noted with ECV compared to ECU colonoscopy. Conclusions  Although safe, the newer ECV did not significantly improve ADR compared to ECU and HD colonoscopy. Further device modification is needed to increase the overall ADR and PDR.

Adenoma detection by Endocuff-assisted versus standard colonoscopy in routine practice: a cluster-randomised crossover trial

OBJECTIVE

Endocuff Vision (ECV) is the second generation of a device designed to improve polyp detection. The aim of this study was to evaluate its impact on adenoma detection rate (ADR) in routine colonoscopy.

DESIGN

This cluster-randomised crossover trial compared Endocuff-assisted (ECV+) with standard (ECV-) colonoscopy. Two teams of 11 endoscopists each with prior ECV experience, balanced in terms of basal ADR, gender and case volume were compared. In randomised fashion, the teams started with ECV+ or ECV- and switched group after inclusion of half of the cases. The main outcome criterion was ADR difference between ECV+ and ECV-. Subgroup analysis was done for physicians with low and high ADR (< or ≥ 25%).

RESULTS

During two periods of 20 and 21 weeks, respectively, the 22 endoscopists included 2058 patients (1032 ECV- vs 1026 ECV+, both groups being comparable). Overall ADR for both groups taken together was higher with ECV (39.2%) than without (29.4%; p<0.001) irrespective of the sequence of use (ECV+ or ECV- first), but mostly in adenomas <1 cm. In the physician subgroup analysis, only high detectors showed a significant ADR increase (from 31% to 41%, p<0.001), while the increase in the low detectors was not significant (from 24% to 30%, p=0.11). ECV had a positive impact in all colonic locations, except for the rectum. No ECV- related complication was reported.

CONCLUSION

We observed a significant ADR difference of approximately 10% by the use of ECV. By subgroup analysis, this increase was significant only in physicians classified as high detectors.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov (NCT03344055).

Lower Adenoma Miss Rate of Computer-Aided Detection-Assisted Colonoscopy vs Routine White-Light Colonoscopy in a Prospective Tandem Study

BACKGROUND AND AIMS

Up to 30% of adenomas might be missed during screening colonoscopy-these could be polyps that appear on-screen but are not recognized by endoscopists or polyps that are in locations that do not appear on the screen at all. Computer-aided detection (CADe) systems, based on deep learning, might reduce rates of missed adenomas by displaying visual alerts that identify precancerous polyps on the endoscopy monitor in real time. We compared adenoma miss rates of CADe colonoscopy vs routine white-light colonoscopy.

METHODS

We performed a prospective study of patients, 18-75 years old, referred for diagnostic, screening, or surveillance colonoscopies at a single endoscopy center of Sichuan Provincial People's Hospital from June 3, 2019 through September 24, 2019. Same day, tandem colonoscopies were performed for each participant by the same endoscopist. Patients were randomly assigned to groups that received either CADe colonoscopy (n=184) or routine colonoscopy (n=185) first, followed immediately by the other procedure. Endoscopists were blinded to the group each patient was assigned to until immediately before the start of each colonoscopy. Polyps that were missed by the CADe system but detected by endoscopists were classified as missed polyps. False polyps were those continuously traced by the CADe system but then determined not to be polyps by the endoscopists. The primary endpoint was adenoma miss rate, which was defined as the number of adenomas detected in the second-pass colonoscopy divided by the total number of adenomas detected in both passes.

RESULTS

The adenoma miss rate was significantly lower with CADe colonoscopy (13.89%; 95% CI, 8.24%-19.54%) than with routine colonoscopy (40.00%; 95% CI, 31.23%-48.77%, P<.0001). The polyp miss rate was significantly lower with CADe colonoscopy (12.98%; 95% CI, 9.08%-16.88%) than with routine colonoscopy (45.90%; 95% CI, 39.65%-52.15%) (P<.0001). Adenoma miss rates in ascending, transverse, and descending colon were significantly lower with CADe colonoscopy than with routine colonoscopy (ascending colon 6.67% vs 39.13%; P=.0095; transverse colon 16.33% vs 45.16%; P=.0065; and descending colon 12.50% vs 40.91%, P=.0364).

CONCLUSIONS

CADe colonoscopy reduced the overall miss rate of adenomas by endoscopists using white-light endoscopy. Routine use of CADe might reduce the incidence of interval colon cancers. chictr.org.cn study no: ChiCTR1900023086.

State of the Science on Quality Indicators for Colonoscopy and How to Achieve Them

Colonoscopy is a safe and effective tool, but operator dependent. Room for improvement in the quality of colonoscopy is the impetus for the development and measurement of colonoscopy quality indicators and the focus of many efforts to improve colonoscopy quality indicator prevention and control in provider practices and health systems. We present the preprocedural, intraprocedural, and postprocedural quality indicators and benchmarks for colonoscopy. Every provider and practice must make a commitment to performing high-quality colonoscopy and implement and monitor quality metrics. There are a variety of tools available to assist in improving quality indicators that range from distal attachment devices to education and feedback. Although technology can help, it is not a substitute for proper technique. The commitment also requires provider feedback through audits and report cards. The impact of these efforts on patient outcomes is an important area of further research.

The Case for High-Quality Colonoscopy Remaining a Premier Colorectal Cancer Screening Strategy in the United States

Most colorectal cancer screening in the United States occurs in the opportunistic setting, where screening is initiated by a patient-provider interaction. Colonoscopy provides the longest-interval protection, and high-quality colonoscopy is ideally suited to the opportunistic setting. Both detection and colonoscopic resection have improved as a result of intense scientific investigation. Further improvements in detection are expected with the introduction of artificial intelligence programs into colonoscopy platforms. We may expect recommended intervals or colonoscopy after negative examinations performed by high-quality detectors to expand beyond 10 years. Thus, high-quality colonoscopy remains an excellent approach to colorectal cancer screening in the opportunistic setting.

Impact of water filling on terminal ileum intubation with a distal-tip mucosal exposure device

BACKGROUND AND AIMS

Endocuff improves detection at colonoscopy but seems to impede terminal ileal (TI) intubation. We assessed the impact of Endocuff Vision (EV) on TI intubation using adult or pediatric colonoscopes and evaluated whether filling the cecum with gas versus water affected the impact of EV on TI intubation.

METHODS

Using a prospectively recorded quality control database, we explored the impact of EV on TI intubation in ≤1 minute. We used adult and pediatric colonoscopes and tested the effect of filling the cecum with gas versus water. If the initial attempt failed, then the alternative (water vs gas) was tried as a rescue method.

RESULTS

TI intubation in ≤1 minute occurred in 91% of colonoscopies without EV versus 65% with EV, but the use of the pediatric colonoscope with EV had a higher success rate for TI intubation in ≤1 minute compared with the adult colonoscope with EV (73% vs 57%, P = .043). TI intubation in ≤1 minute was more successful with EV when the cecum was filled with water rather than gas (74% vs 56%, P = .019), but the benefit of water filling was limited to the adult colonoscope with EV. When EV was in place, water filling was more successful as a rescue method of TI intubation (58% vs 21%, P = .011).

CONCLUSIONS

EV adversely affects TI intubation, particularly for adult colonoscopes. Water filling of the cecum mitigates the impact of EV on TI intubation with adult colonoscopes.

Surveying ADR Knowledge and Practices Among US Gastroenterologists

BACKGROUND

The adenoma detection rate (ADR) is of primary importance to the quality of screening colonoscopy. An online survey was conducted to assess knowledge and practices on ADR.

METHODS

Paid questionnaire distributed by email. Eligible respondents were board certified gastroenterologists who perform >80 colonoscopies per month with 3 to 35 years practice after fellowship.

RESULTS

There were 250 respondents. In total, 39% were unaware that ADR applies only to screening colonoscopies and 76% incorrectly answered that ADR includes sessile-serrated polyps/adenomas. A total of 51% of respondents incorrectly believe the threshold is set at 25% because 25% is a national ADR average. Many also believe the threshold depends on the patient population (current evidence suggests adjusting ADR for factors other than age and sex is unnecessary). 75% ranked ADR as highly important. 80% reported tracking ADR. A busy practice was the most common reason for not tracking ADR. Caps, chromoendoscopy, and good bowel preparation were viewed as valuable for improving ADR (this is true except for caps). High-definition colonoscopes and education were considered less valuable, despite evidence indicating that both are associated with improved ADR. In total, 57% reported not sharing ADR information with their patients, and 59% reported that no patients in the last 6 months asked for their ADR.

CONCLUSIONS

The importance of ADR as a quality measure is well understood, but there are misconceptions among gastroenterologists regarding the definition and measurement of ADR, and which methods are proven to increase ADR. Patients are having very little impact on ADR measurement.

Endocuff-Assisted versus Cap-Assisted Colonoscopy Performed by Trainees: A Retrospective Study

Background/Aims

The adenoma detection rate (ADR) of screening colonoscopies performed by trainees is often lower than that of colonoscopies performed by experts. The effcacy of cap-assisted colonoscopy (CAC) in adenoma detection is well documented, especially that of CACs performed by trainees. Endocuff, a new endoscopic cap, is reportedly useful for adenoma detection; however, no trials have compared the effcacy of Endocuff-assisted colonoscopy (EAC) and CAC conducted by trainees. Therefore, the present study retrospectively compared the effcacy between EAC and CAC in trainees.

Methods

This was a single-center, retrospective study involving 305 patients who underwent either EAC or CAC performed by three trainees between January and December 2018. We evaluated the ADR, mean number of adenomas detected per patient (MAP), cecal intubation rate, cecal intubation time, and occurrence of complications between the EAC and CAC groups.

Results

The ADR was significantly higher in the EAC group than in the CAC group (54.3% vs. 37.3%, p=0.019), as was the MAP (1.36 vs. 0.74, p=0.003). No significant differences were found between the groups with respect to the cecal intubation rate or cecal intubation time. No major complications occurred in either group.

Conclusions

Our results suggest that EAC exhibits increased ADR and MAP compared to CAC when performed by trainees.

Comparison of colon adenoma detection rates using cap-assisted and Endocuff-assisted colonoscopy: a randomized controlled trial

Objectives and study aim  Colonoscopy prevents colorectal cancer by removing adenomatous polyps, but missed adenomas lead to interval cancers. Different devices have been used to increase adenoma detection rates (ADR). Two such devices of interest are the transparent cap (Olympus) and Endocuff (ARC Medical). Our study aimed to compare differences in ADR between Endocuff-assisted colonoscopy (EAC), cap-assisted colonoscopy (CAC) and standard colonoscopy (SC). Patients and methods  A sample size of 126 subjects was calculated to determine an effect size of 30 %. Patients undergoing screening or surveillance colonoscopy between March 2016 and January 2017 were randomized to SC, CAC or EAC groups. Three experienced endoscopists performed all colonoscopies. Patient demographics, procedure indication, Boston Bowel Prep Score (BBPS), withdrawal time, polyp size, location, histopathology, were analyzed. Results  There was no difference in ADR (52 %, 40 % and 54 %) in the SC, CAC and EAC groups respectively ( P  = 0.4). Similar findings were also observed for proximal ADR (45 %, 35 %, and 50 %, P  = 0.4) and SSA detection rate (16 %, 14 %, and 23 %, P  = 0.5). EAC detected higher mean ADR per colonoscopy compared to CAC (1.70 vs 0.76, P  = 0.01). However, there was no significant difference in mean ADR per positive colonoscopy (2.08, 1.63, and 2.59, P  = 0.21). Conclusion  In a randomized controlled trial comparing AC to CAC and SC, neither device conferred additional benefits in ADR among high detectors. When comparing each device, EAC may be better than CAC at detecting more total adenomas.

EndoCuff-assisted colonoscopy could improve adenoma detection rate: A meta-analysis of randomized controlled trials

OBJECTIVE

This meta-analysis aimed to evaluate whether EndoCuff-assisted colonoscopy (EAC) could improve adenoma detection rate (ADR) compared with standard colonoscopy (SC).

METHODS

PubMed, EMBASE, Scopus, Cochrane Library, and Google Scholar databases were searched for articles published up to March 2019. All pure randomized controlled trials comparing ADR between EAC and SC groups were included. Dichotomous data were pooled to obtain the odds ratio with a 95% confidence interval (CI), whereas continuous data were pooled using a mean difference with 95% CI. Review Manager Version 5.3 was used for data analysis.

RESULTS

Thirteen randomized controlled trials consisting of 9038 patients (EAC: 4574; SC: 4464) were included. The EAC group showed significant superiority over the SC group in ADR (odds ratio 1.37, 95% CI 1.15-1.62). However, there were no differences between the EAC and SC groups in adverse events, cecal intubation rate, and cecal intubation time.

CONCLUSIONS

EAC could significantly improve ADR without increasing adverse events, especially for operators with low ADRs. In addition, no significant difference was observed in cecal intubation time and cecal intubation rate between EAC and SC.

Real-time automatic detection system increases colonoscopic polyp and adenoma detection rates: a prospective randomised controlled study

OBJECTIVE

The effect of colonoscopy on colorectal cancer mortality is limited by several factors, among them a certain miss rate, leading to limited adenoma detection rates (ADRs). We investigated the effect of an automatic polyp detection system based on deep learning on polyp detection rate and ADR.

DESIGN

In an open, non-blinded trial, consecutive patients were prospectively randomised to undergo diagnostic colonoscopy with or without assistance of a real-time automatic polyp detection system providing a simultaneous visual notice and sound alarm on polyp detection. The primary outcome was ADR.

RESULTS

Of 1058 patients included, 536 were randomised to standard colonoscopy, and 522 were randomised to colonoscopy with computer-aided diagnosis. The artificial intelligence (AI) system significantly increased ADR (29.1%vs20.3%, p<0.001) and the mean number of adenomas per patient (0.53vs0.31, p<0.001). This was due to a higher number of diminutive adenomas found (185vs102; p<0.001), while there was no statistical difference in larger adenomas (77vs58, p=0.075). In addition, the number of hyperplastic polyps was also significantly increased (114vs52, p<0.001).

CONCLUSIONS

In a low prevalent ADR population, an automatic polyp detection system during colonoscopy resulted in a significant increase in the number of diminutive adenomas detected, as well as an increase in the rate of hyperplastic polyps. The cost-benefit ratio of such effects has to be determined further.

TRIAL REGISTRATION NUMBER

ChiCTR-DDD-17012221; Results.

Impact of moderate versus deep sedation on adenoma detection rate in index average-risk screening colonoscopies

BACKGROUND AND AIMS

The debate between moderate sedation versus deep sedation for index average-risk screening colonoscopies is well known to gastroenterologists. Ensuring the best of all metrics to perform quality colonoscopies for colon cancer prevention is paramount for both patients and physicians alike, because colon cancer remains the leading cause of cancer death and is the most-used screening tool in the United States. The aim of this study was to determine if moderate sedation versus deep sedation affects outcomes of adenoma detection rate (ADR) or polyp detection rate (PDR) in index, average-risk colonoscopies for colon cancer screening.

METHODS

A retrospective, single, tertiary care outpatient center study of 585 healthy average-risk patients who underwent index screening colonoscopy between June 1, 2015 to December 31, 2015 (moderate sedation only) and June 1, 2016,to December 31, 2016 (deep sedation only) was performed after Institutional Review Board approval. Demographic data and polyp details were collected to determine ADR and PDR. Patients who were not average risk were excluded from the study.

RESULTS

A total of 585 index average-risk screening colonoscopies were included in this study with 57.7% moderate sedation and 42.2% deep sedation. Neither ADR nor PDR was significantly different between the 2 groups (44.1% vs 38.5% [P = .18] and 71.9% vs 67.6% [P = .27], respectively).

CONCLUSIONS

In index average-risk screening colonoscopies, deep sedation appears to have no benefit compared with moderate sedation for ADR and PDR.

Randomized control trial of adenoma detection rate in Endocuff-assisted colonoscopy versus transparent hood-assisted colonoscopy

BACKGROUND AND AIM

Transparent hood-assisted colonoscopy (TAC) has been reported to improve the cecal insertion rate and adenoma detection rate (ADR). An endoscopic cap (Endocuff) with two rows of soft wings was recently developed to improve ADR, by flattening the mucosal folds during withdrawal. This randomized prospective control study aimed to compare ADR between Endocuff-assisted colonoscopy (EAC) and TAC.

METHODS

A total of 513 patients undergoing colon adenoma screening were included. EAC was performed in 256 patients and TAC in 260 patients. Cecal intubation rate, cecal intubation time, ADR, and mean adenoma number per patient (MAP) were investigated in both groups (clinical trial registration: UMIN000016278).

RESULTS

We excluded six patients in the EAC group and two patients in the TAC group because of colonic stenosis due to colonic adenocarcinomas. Finally, 250 patients (151 men/99 women, median age 62.1 years) were assigned to EAC and 258 patients (165 men/93 women, median age 64.3 years) were assigned to TAC. There were no significant differences in cecal intubation rate, intubation time, withdrawal time, and cleanliness score between groups. The ADR was 50.8% in EAC and 52.7% in TAC, with no significant difference (P = 0.666). The MAP was 1.35 in EAC and 1.20 in TAC, with no significant difference (P = 0.126). However, The MAP of diminutive adenomas (< 5 mm) tended to be higher in EAC than in TAC (P = 0.077). There was no significant difference in MAP in each segment between groups.

CONCLUSIONS

Endocuff-assisted colonoscopy might be equivalent to TAC in cecal intubation time, ADR, and MAP.

Cost-effectiveness of adding Endocuff® to standard colonoscopies for interval colorectal cancer screening

Background and aims: Higher screening colonoscopy adenoma detection rates (ADRs) correlate with reduced risk of interval colorectal cancer (CRC). The Endocuff® device has been shown to improve ADRs compared to standard colonoscopy (SC). This cost-effectiveness analysis compared interval CRC screening using Endocuff®-assisted colonoscopy (EC) vs SC. Methods: A decision-analytic Markov model followed patients through screening, CRC diagnosis, progression, remission, and death. ADRs, CRC progression, and utilities were from literature. CRC incidence, stage distribution, and mortality were from the Surveillance, Epidemiology, and End Results (SEER) and SEER-Medicare linked databases. Screening and annual patient costs were from public databases and literature. Endocuff® device average sales price was applied. Lifetime device and medical costs were evaluated separately for device purchaser, health plan, and accountable care organization (ACO) perspectives. Results: Consistent use of EC instead of SC was expected to reduce lifetime risks of interval CRC and related death by 0.98% and 0.19%, respectively, preventing one case per 102 patients and one death per 526 patients. Survival and quality-of-life (QoL) improved by 0.025 life-years and 0.011 quality-adjusted life-years (QALYs) per patient on average. EC instead of SC led to incremental cost-effectiveness ratios to the device purchaser of $4,421 per life-year gained and $9,843 per QALY gained, and $199 or $87 average cost-savings per patient to the health plan or ACO, respectively. Conclusion: Endocuff® for screening colonoscopies was expected to reduce interval CRC incidence and death, improve QoL, and be cost-effective to the device purchaser and cost-saving to a health plan or ACO.

Effect of Endocuff use on colonoscopy outcomes: A systematic review and meta-analysis

BACKGROUND

Endocuff - a plastic device with flexible projections - mounted on the distal tip of the colonoscope, promises improved colonic mucosa inspection.

AIM

To elucidate the effect of Endocuff on adenoma detection rate (ADR), advanced ADR (AADR) and mean number of adenomas per colonoscopy (MAC).

METHODS

Literature searches identified randomized-controlled trials evaluating Endocuff-assisted colonoscopy (EAC) vs conventional colonoscopy (CC) in terms of ADR, AADR and MAC. The effect size on study outcomes was calculated using fixed or random effect model, as appropriate, and it is shown as relative risk (RR) [95% confidence interval (CI)] and mean difference (MD) (95%CI). The rate of device removal in EAC arms was also calculated.

RESULTS

We identified nine studies enrolling 6038 patients. All studies included mixed population (screening, surveillance and diagnostic examinations). Seven and two studies evaluated the first and the second-generation device, respectively. EAC was associated with increased ADR compared to CC [RR (95%CI): 1.18 (1.05-1.32); Ι² = 71%]; EAC benefits more endoscopists with ADR ≤ 35% compared to those with ADR > 35% [RR (95%CI): 1.37 (1.08-1.74); Ι² = 49% vs 1.10 (0.99-1.24); Ι² = 71%]. In terms of AADR and MAC, no difference was detected between EAC and CC [RR (95%CI): 1.03 (0.85-1.25); Ι² = 15% and MD (95%CI): 0.30 (-0.17-0.78); Ι² = 99%]. Subgroup analysis did not show any difference between the two device generations regarding all three endpoints. In EAC arms, the device had to be removed in 3% (95%CI: 2%-5%) of the cases mainly due to tortuous sigmoid or presence of diverticula along it.

CONCLUSION

EAC increases ADR compared to CC, especially for endoscopists with lower ADR. On the other hand, no significant effect on AADR and MAC was detected.

Does Increased Adenoma Detection Reduce the Risk of Colorectal Cancer, and How Good Do We Need to Be?

PURPOSE OF REVIEW

Colorectal cancer (CRC) is largely preventable with colonoscopy and other screening modalities. However, the effectiveness of screening and surveillance depends on the quality of the colonoscopy exam. Adenoma detection rate (ADR) is the best-validated metric by which we measure individual physicians' performance.

RECENT FINDINGS

Recent evidence suggests that ADR benchmarks may be inappropriately low. There is proof that improving ADR leads to significant reductions in post-colonoscopy CRC (PCCRC). Two studies have demonstrated that when a colonoscopy is performed by physicians with higher ADRs, patients are less likely to have advanced adenomas on surveillance and less likely to develop or die from PCCRC. Finally, there is at least some evidence that higher ADRs do not lead to more cumulative surveillance exams. The ADR is a useful outcome measure that can provide individual endoscopists and their patients with information about the likelihood of developing PCCRC. To achieve the lowest possible PCCRC rate, we should be striving for higher ADRs. While strategies and innovations may help a bit in improving ADRs, our efforts should focus on ensuring a complete mucosal exam for each patient. Behavioral psychology theories may provide useful frameworks for studying motivating factors that drive a careful exam.

Study on detection rate of polyps and adenomas in artificial-intelligence-aided colonoscopy

BACKGROUND/AIM

To study the impact of computer-aided detection (CADe) system on the detection rate of polyps and adenomas in colonoscopy.

MATERIALS AND METHODS

A total of 1026 patients were prospectively randomly scheduled for colonoscopy with (the CADe group, CADe) or without (the control group, CON) the aid of the CADe system, together with visual notification and voice alarm, so as to compare the detection rate of polyp.

RESULTS

Compared with group CON, the detection rate of adenomas increased in group CADe, the average number of adenomas increased, the number of small adenomas increased, the number of proliferative polyps increased, and the differences were statistically significant (P < 0.001), but the comparison for the number of larger adenomas showed no significant difference between the groups (P> 0.05).

CONCLUSIONS

The CADe system is feasible for increasing the detection of polyps and adenomas in colonoscopy.

To cap/cuff or ring: do distal attachment devices improve the adenoma detection?

Colonoscopy reduces the risk of colorectal cancer, by interrupting the adenoma-carcinoma sequence enabling the detection and removal of adenomas before they turn into colorectal cancer. Colonoscopy has its limitations as adenoma miss rates as high as 25% have been reported. The reasons for missed pathology are complicated and multi-factorial. The recent drive to improve adenoma detection rates has led to a plethora of new technologies. Areas covered: An increasing number of advanced endoscopes and distal attachment devices have appeared in the market. Advanced endoscopes aim to improve mucosal visualization by widening the field of view. Distal attachment devices aim to increase adenoma detection behind folds by flattening folds on withdrawal. In this review article, we discuss the three following distal attachment devices: the transparent cap, the Endocuff, and the Endoring. Expert commentary: The authors believe that the distal attachment devices will have a greater benefit for endoscopists with low baseline adenoma detection rates.

Colonoscopy attachments for the detection of precancerous lesions during colonoscopy: A review of the literature

Although colonoscopy has been proven effective in reducing the incidence of colorectal cancer through the detection and removal of precancerous lesions, it remains an imperfect examination, as it can fail in detecting up to almost one fourth of existing adenomas. Among reasons accounting for such failures, is the inability to meticulously visualize the colonic mucosa located either proximal to haustral folds or anatomic curves, including the hepatic and splenic flexures. In order to overcome these limitations, various colonoscope attachments aiming to improve mucosal visualization have been developed. All of them - transparent cap, Endocuff, Endocuff Vision and Endorings - are simply mounted onto the distal tip of the scope. In this review article, we introduce the rationale of their development, present their mode of action and discuss in detail the effect of their implementation in the detection of lesions during colonoscopy.

New technologies improve adenoma detection rate, adenoma miss rate, and polyp detection rate: a systematic review and meta-analysis

BACKGROUND AND AIMS

The need to increase the adenoma detection rate (ADR) for colorectal cancer screening has ushered in devices that mechanically or optically improve conventional colonoscopy. Recently, new technology devices (NTDs) have become available. We aimed to compare the ADR, polyp detection rate (PDR), and adenoma miss rate (AMR) between NTDs and conventional colonoscopy and between mechanical and optical NTDs.

METHODS

MEDLINE and Embase databases were searched from inception through September 2017 for articles or abstracts reporting ADR, PDR, and AMR with NTDs. Randomized controlled trials and case-control studies with >10 subjects were included. Primary outcomes included ADR, PDR, and AMR odds ratio (OR) between conventional colonoscopy and NTDs. Secondary outcomes included cecal intubation rates, adverse events, cecal intubation time, and total colonoscopy time.

RESULTS

From 141 citations, 45 studies with 20,887 subjects were eligible for ≥1 analyses. Overall, the ORs for ADR (1.35; 95% confidence interval [CI] 1.24-1.47; P < .01) and PDR (1.51; 95% CI, 1.37-1.67; P < .01) were higher with NTDs. Higher ADR (OR, 1.52 vs 1.25; P = .035) and PDR (OR, 1.63 vs 1.10; P ≤ .01) were observed with mechanical NTDs. The overall AMR with NTDs was lower compared with conventional colonoscopy (OR, .19; 95% CI, .14-.26; P < .01). Mechanical NTDs had lower AMRs compared with optical NTDs (OR, .10 vs .33; P < .01). No differences in cecal intubation rates, cecal intubation time, or total colonoscopy time were found.

CONCLUSIONS

Newer endoscopic technologies are an effective option to improve ADR and PDR and decrease AMR, particularly with mechanical NTDs. No differences in operability and safety were found.

Faster colonoscope withdrawal time without impaired detection using EndoRings

BACKGROUND AND STUDY AIMS

 Mucosal exposure devices on the colonoscope tip have improved detection. We evaluated detection and procedure times in colonoscopies performed with EndoRings.

PATIENTS AND METHODS

 We had 14 endoscopists in a university practice trial EndoRings. We compared detection and procedure times to age- and indication-matched procedures by the same endoscopists.

RESULTS

 There were 137 procedures with EndoRings. The adenoma detection rate was 44 % with EndoRings vs. 39 % without ( P  = 0.39). Mean adenomas per colonoscopy (standard deviation) was 1.2 (2.3) with EndoRings vs. 0.9 (1.6) without ( P  = 0.055). Mean insertion time with EndoRings was 6.2 (3.2) minutes vs. 6.6 (6.7) minutes without ( P  = 0.81). Mean withdrawal time with EndoRings in all patients with or without polypectomy was 12.2 (5.3) minutes and 16.1 (10.3) minutes without ( P  = 0.0005).

CONCLUSION

 EndoRings may allow faster withdrawal during colonoscopy without any reduction in detection. Prospective trials with mucosal exposure devices targeting procedure times as primary endpoints are warranted.

High-definition colonoscopy versus Endocuff versus EndoRings versus full-spectrum endoscopy for adenoma detection at colonoscopy: a multicenter randomized trial

BACKGROUND AND AIMS

Devices used to improve polyp detection during colonoscopy have seldom been compared with each other.

METHODS

We performed a 3-center prospective randomized trial comparing high-definition (HD) forward-viewing colonoscopy alone to HD with Endocuff to HD with EndoRings to the full spectrum endoscopy (FUSE) system. Patients were age ≥50 years and had routine indications and intact colons. The study colonoscopists were all proven high-level detectors. The primary endpoint was adenomas per colonoscopy (APC).

RESULTS

Among 1188 patients who completed the study, APC with Endocuff (APC mean ± standard deviation: 1.82 ± 2.58), EndoRings (1.55 ± 2.42), and standard HD colonoscopy (1.53 ± 2.33) were all higher than FUSE (1.30 ± 1.96; P < .001 for APC). The APC for Endocuff was higher than standard HD colonoscopy (P = .014). Mean cecal insertion times with FUSE (468 ± 311 seconds) and EndoRings (403 ± 263 seconds) were both longer than with Endocuff (354 ± 216 seconds; P = .006 and .018, respectively).

CONCLUSIONS

For high-level detectors at colonoscopy, forward-viewing HD instruments dominate the FUSE system, indicating that for these examiners image resolution trumps angle of view. Further, Endocuff is a dominant strategy over EndoRings and no mucosal exposure device on a forward-viewing HD colonoscope. (Clinical trial registration number: NCT02345889.).

Efficacy of Endocuff-assisted colonoscopy in the detection of colorectal polyps

BACKGROUND AND STUDY AIMS

Colonoscopy is the gold standard for detecting colorectal adenomas and cancers. Endoscopic surveillance has been shown to be effective for preventing colorectal cancer. Although detection of colorectal polyps at an early stage is important, endoscopic visualization of early neoplasia can be difficult. The Endocuff is a new device that can be attached to the tip of the colonoscope to hold the colonic folds away from the field of view during withdrawal. The aim of this study was to compare the adenoma detection rate (ADR) and the mean number of adenomas detected per patient (MAP) achieved using Endocuff-assisted colonoscopy (EAC) and standard colonoscopy (SC).

PATIENTS AND METHODS

This randomized prospective study was conducted at two academic endoscopy departments in Japan. A total of 447 patients underwent a complete colonoscopic examination between April 2015 and September 2015. The EAC group included 239 patients. The cecal intubation rate, insertion time, withdrawal time, pain score, complications, polyp detection rate (PDR), ADR, the mean number of polyps detected per patient (MPP), and the MAP were assessed.

RESULTS

There were no differences between the EAC and SC groups in terms of cecal intubation rate, insertion time, withdrawal time, or pain scores. The PDR in patients increased by about 12 % (61.9 % vs. 49.2 %, P  = 0.013) and ADR increased by 15 % (52.5 % vs. 39.2 %, P  = 0.001) with the use of the Endocuff. The advanced ADR was higher in the EAC group but no statistically significant difference was found (7.7 % vs. 4.6 %, P  = 0.17). Both MPP and MAP were also higher in the EAC group (mean ± SD: 1.33 ± 1.43 vs. 0.83 ± 0.99 per patient; P  < 0.01, 1.11 ± 1.41 vs. 0.66 ± 0.99 per patient; P  < 0.01, respectively). No major complications occurred.

CONCLUSIONS

 EAC not only enabled a higher ADR but also significantly increased the mean number of adenomas identified per patient, as compared with SC.

Impact of a new distal attachment on colonoscopy performance in an academic screening center

BACKGROUND AND AIMS

Distal attachments placed on the colonoscope tip may positively affect performance by assisting insertion and polyp detection. The original Endocuff (ARC Medical Design, Leeds, United Kingdom) appears to improve adenoma detection rate (ADR), but no data assess the performance of the second-generation Endocuff Vision.

METHODS

A pilot service evaluation study (April 2013 to September 2014) was conducted on patients with positive fecal occult blood tests within the National Bowel Cancer Programme during 3 consecutive periods: precuff/no device used, during-cuff/device used, and postcuff/no device used. During the middle period the use of the Endocuff Vision by the 4 screening-accredited colonoscopists was discretional (nonrandomized design). Data were analyzed using pairwise comparisons during the 3 designated periods to examine key performance indicators: adenoma detection, procedural time, sedation requirements, and patient comfort.

RESULTS

Four hundred ten complete colonoscopies were performed (137 precuff, 136 cuff, and 137 postcuff period). Overall, there was a notable increase in the mean ADR of 16% (P < .03) and in the mean number adenoma per procedure (MAP) of 83% (P = .007) from precuff to cuff period. The mean cecal intubation time was statistically lower during the cuff period (7 minutes) in relation to the precuff period (8 minutes; reduction of 12.5%, P = .002) and the postcuff period (9 minutes; increase of 28.6%, P = .002). The mean negative colonoscopy withdrawal time was also significantly lower during the cuff period (8 minutes, 30 seconds) when compared with the precuff (12 minutes) or postcuff period (9 minutes, 45 seconds; P ≤ .001). Multivariate regression analysis showed that the use of the Endocuff Vision was not associated with sedation requirements or patient discomfort scores. No adverse events were reported from the use of the Endocuff Vision, although it was electively removed in 6 patients where severe sigmoid colon diverticulosis was encountered and 2 patients because of discomfort during anal insertion.

CONCLUSIONS

In this pilot service evaluation study, the use of the Endocuff Vision appears to be associated with an improvement in overall colonoscopy operator performance. We found increased ADR and MAP as well as decreased time for colonoscope insertion and withdrawal time with no increase in sedation requirements or patient discomfort.

Polyp Resection and Removal Procedures: Insights From the 2017 Digestive Disease Week

Colorectal cancer (CRC) is an important public health issue not only because of its high incidence but also for its high mortality rate. When CRC is diagnosed at an early stage, the 5-year relative survival rate reaches 89.9%. However, only 39% of patients with CRC are diagnosed at this stage. Screening decreases both the incidence of CRC and the number of CRC-related deaths. There are several options available for screening, and colonoscopy is one of the most common methods utilized in the United States. Screening colonoscopy is associated with durable protection from CRC. However, it has become increasingly apparent in recent years that polyp detection and resection have not been completely effective in clinical practice. Because the protective benefit of colonoscopy is variable, quality benchmarks have been established to improve its clinical effectiveness. The adenoma detection rate (ADR) directly correlates with the incidence and mortality of postcolonoscopy (or interval) CRCs. It is now routine to remove large polyps (≥20 mm) using advanced techniques for endoscopic mucosal resection (EMR) and endoscopic submucosal dissection (ESD). Recent studies have helped identify which colorectal lesions are at higher risk of invasive cancer and would benefit from a complete en bloc resection. Such data may guide endoscopists in making a decision on whether to use ESD or EMR for removal of large lesions. An increased number of studies have reported on the efficacy and safety of cold snare resection, even for larger polyps. These data suggest that cold snare resection may be as effective, and perhaps safer, than hot snare resection for polyps up to 1 to 2 cm in size. However, data on the threshold for cold snare resection and the value of submucosal injectates are still lacking. Use of submucosal injection is generally preferred for larger polyps, particularly those located in the proximal colon, where the colonic wall is thinner.

Polyp detection at colonoscopy: Endoscopist and technical factors

The adenoma detection rate (ADR) has emerged as the most important quality measure in colonoscopy, as it predicts the risk of interval cancer after colonoscopy. Measuring and improving ADR is the central focus of the current quality movement in colonoscopy. High ADRs can be achieved by a colonoscopist with a thorough understanding of the wide range of endoscopic appearances of precancerous lesions in the colorectum, effective bowel preparation, and meticulous technique using high definition colonoscopes. The knowledgeable and effective examiner needs no adjunctive devices or techniques to achieve master level ADRs. However, measurement reveals that many colonoscopists have ADRs that are below recommended minimum thresholds or below master levels. These colonoscopists, and even master level performers, can choose from a variety of adjunctive tools to improve ADR. This review describes these tools according to whether they are non-device methods (e.g. double right colon examination, patient position change, water exchange), mucosal exposure devices (wide angle colonoscopy, fold flattening devices), and lesion highlighting techniques (e.g. chromoendoscopy, electronic chromoendoscopy).

New device to implement the adenoma detection rate

It is well-known that colonoscopy is considered the gold standard for colon cancer prevention. Although performed by experienced endoscopists, the matter remains of polyps missed during this examination. The reasons may include the size, shape and location of the lesions. Many colorectal cancer screening programs have been proposed to increase the adenoma detection rate. The substantial difference between these methods is whether the improvement in vision, particularly the detection of irregularities of the mucosa, is inside the endoscope electronic components (magnification, wide-angle vision, narrow band imaging, flexible spectral imaging colour enhancement, i-Scan) or outside the same, by the use of specific caps (EndoCuff, EndoVision, EndoRings). Endocuff is a plastic device mounted at the end of the scope with a constant vision field of the entire colon. The aim of this study is to explore the potential clinical and technical benefits of Endocuff.

New endoscopes and add-on devices to improve colonoscopy performance

Colonoscopy is the gold standard for colorectal cancer prevention; however, it is still an imperfect modality. Precancerous lesions can be lost during screening examinations, thus increasing the risk of interval cancer. A variety of factors either patient-, or endoscopist dependent or even the procedure itself may contribute to loss of lesions. Sophisticated modalities including advanced technology endoscopes and add-on devices have been developed in an effort to eliminate colonoscopy's drawbacks and maximize its ability to detect potentially culprit polyps. Novel colonoscopes aim to widen the field of view. They incorporate more than one cameras enabling simultaneous image transmission. In that way the field of view can expand up to 330°. On the other hand a plethora of add-on devices attachable on the standard colonoscope promise to detect lesions in the proximal aspect of colonic folds either by offering a retrograde view of the lumen or by straightening the haustral folds during withdrawal. In this minireview we discuss how these recent advances affect colonoscopy performance by improving its quality indicators (cecal intubation rate, adenoma detection rate) and other metrics (polyp detection rate, adenomas per colonoscopy, polyp/adenoma miss rate) associated with examination's outcomes.