Emerging technological advancements in colonoscopy: Third Eye® Retroscope® and Third Eye® Panoramic(TM) , Fuse® Full Spectrum Endoscopy® colonoscopy platform, Extra-Wide-Angle-View colonoscope, and NaviAid(TM) G-EYE(TM) balloon colonoscope

Prevalence of colonoscopy-related adverse events in older adults aged over 65 years: a systematic review and meta-analysis

BACKGROUND

This study aims to assess the occurrence of colonoscopy-related adverse events (AEs) in adults aged over 65 years, as there has been a significant increase in the prevalence of colonoscopies among the elderly compared to two decades ago.

METHODS

A comprehensive search was conducted on 3 June 2024, using the PubMed, Embase, and Cochrane Library databases. Meta-analyses were performed using the generalized linear-mixed model, and the results were presented as pooled rates with relevant 95% confidence intervals (CIs).

RESULTS

We retrieved a total of 15 417 records and included 13 population-based studies. The overall rates of colonoscopy-related perforation and bleeding in the elderly population were 7.8 (95% CI 5.5-11.2; I2  = 94%) and 23.5 (95% CI 9.0-61.3; I2  = 100%) per 10 000 colonoscopies, respectively. The " > 80 years" group had a significantly higher risk of perforation (RR 2.55; 95% CI 1.15-5.66; I2  = 79%) and bleeding (RR 1.23; 95% CI 1.02-1.48; I2  = 0%) compared to the "65-80 years" group. For screening colonoscopies, the rates of perforation and bleeding were 8.5 (95% CI 7.1-10.2; I2  = 0%) and 27 (95% CI 9.0-81.0; I2  = 99%) per 10 000 colonoscopies, respectively. For diagnostic colonoscopies, the rates of perforation and bleeding were 18 (95% CI 16.2-20.0; I2  = 1%) and 16 (95% CI 8.1-31.3; I2  = 98%) per 10 000 colonoscopies, respectively. Compared to non-therapeutic colonoscopies, therapeutic procedures exhibited higher rates of both perforation (1.5 vs. 0.4 per 10 000 colonoscopies) and bleeding (7.1 vs. 0.5 per 10 000 colonoscopies). The prevalence of cardiopulmonary AEs in the elderly population is relatively high, although the definition used varies across different studies.

CONCLUSIONS

We conducted a comprehensive analysis on the prevalence of AEs related to colonoscopy in older adults. Overall, the AE rates remain low. However, we emphasize the importance of enhancing safety protocols to further minimize risks, ensuring that the benefits of colonoscopy continue to outweigh the risks, especially for patients over the age of 80.

Use of a Novel Artificial Intelligence System Leads to the Detection of Significantly Higher Number of Adenomas During Screening and Surveillance Colonoscopy: Results From a Large, Prospective, US Multicenter, Randomized Clinical Trial

INTRODUCTION

Adenoma per colonoscopy (APC) has recently been proposed as a quality measure for colonoscopy. We evaluated the impact of a novel artificial intelligence (AI) system, compared with standard high-definition colonoscopy, for APC measurement.

METHODS

This was a US-based, multicenter, prospective randomized trial examining a novel AI detection system (EW10-EC02) that enables a real-time colorectal polyp detection enabled with the colonoscope (CAD-EYE). Eligible average-risk subjects (45 years or older) undergoing screening or surveillance colonoscopy were randomized to undergo either CAD-EYE-assisted colonoscopy (CAC) or conventional colonoscopy (CC). Modified intention-to-treat analysis was performed for all patients who completed colonoscopy with the primary outcome of APC. Secondary outcomes included positive predictive value (total number of adenomas divided by total polyps removed) and adenoma detection rate.

RESULTS

In modified intention-to-treat analysis, of 1,031 subjects (age: 59.1 ± 9.8 years; 49.9% male), 510 underwent CAC vs 523 underwent CC with no significant differences in age, gender, ethnicity, or colonoscopy indication between the 2 groups. CAC led to a significantly higher APC compared with CC: 0.99 ± 1.6 vs 0.85 ± 1.5, P = 0.02, incidence rate ratio 1.17 (1.03-1.33, P = 0.02) with no significant difference in the withdrawal time: 11.28 ± 4.59 minutes vs 10.8 ± 4.81 minutes; P = 0.11 between the 2 groups. Difference in positive predictive value of a polyp being an adenoma among CAC and CC was less than 10% threshold established: 48.6% vs 54%, 95% CI -9.56% to -1.48%. There were no significant differences in adenoma detection rate (46.9% vs 42.8%), advanced adenoma (6.5% vs 6.3%), sessile serrated lesion detection rate (12.9% vs 10.1%), and polyp detection rate (63.9% vs 59.3%) between the 2 groups. There was a higher polyp per colonoscopy with CAC compared with CC: 1.68 ± 2.1 vs 1.33 ± 1.8 (incidence rate ratio 1.27; 1.15-1.4; P < 0.01).

DISCUSSION

Use of a novel AI detection system showed to a significantly higher number of adenomas per colonoscopy compared with conventional high-definition colonoscopy without any increase in colonoscopy withdrawal time, thus supporting the use of AI-assisted colonoscopy to improve colonoscopy quality ( ClinicalTrials.gov NCT04979962).

Ultra-minimally invasive endoscopic techniques and colorectal diseases: Current status and its future

Colorectal diseases are increasing due to altered lifestyle, genetic, and environmental factors. Colonoscopy plays an important role in diagnosis. Advances in colonoscope (ultrathin scope, magnetic scope, capsule) and technological gadgets (Balloon assisted scope, third eye retroscope, NaviAid G-EYE, dye-based chromoendoscopy, virtual chromoendoscopy, narrow band imaging, i-SCAN, etc.) have made colonoscopy more comfortable and efficient. Now in-vivo microscopy can be performed using confocal laser endomicroscopy, optical coherence tomography, spectroscopy, etc. Besides developments in diagnostic colonoscopy, therapeutic colonoscopy has improved to manage lower gastrointestinal tract bleeding, obstruction, perforations, resection polyps, and early colorectal cancers. The introduction of combined endo-laparoscopic surgery and robotic endoscopic surgery has made these interventions feasible. The role of artificial intelligence in the diagnosis and management of colorectal diseases is also increasing day by day. Hence, this article is to review cutting-edge developments in endoscopic principles for the management of colorectal diseases.

Recent advances in devices and technologies that might prove revolutionary for colonoscopy procedures

INTRODUCTION

Colorectal cancer (CRC) is the third most common malignancy and second leading cause of cancer-related mortality in the world. Adenoma detection rate (ADR), a quality indicator for colonoscopy, has gained prominence as it is inversely related to CRC incidence and mortality. As such, recent efforts have focused on developing novel colonoscopy devices and technologies to improve ADR.

AREAS COVERED

The main objective of this paper is to provide an overview of advancements in the fields of colonoscopy mechanical attachments, artificial intelligence-assisted colonoscopy, and colonoscopy optical enhancements with respect to ADR. We accomplished this by performing a comprehensive search of multiple electronic databases from inception to September 2023. This review is intended to be an introduction to colonoscopy devices and technologies.

EXPERT OPINION

Numerous mechanical attachments and optical enhancements have been developed that have the potential to improve ADR and AI has gone from being an inaccessible concept to a feasible means for improving ADR. While these advances are exciting and portend a change in what will be considered standard colonoscopy, they continue to require refinement. Future studies should focus on combining modalities to further improve ADR and exploring the use of these technologies in other facets of colonoscopy.

Endoscopic image-guided laser treatment system based on fiber bundle laser steering

A miniaturized endoscopic laser system with laser steering has great potential to expand the application of minimally invasive laser treatment for micro-lesions inside narrow organs. The conventional systems require separate optical paths for endoscopic imaging and laser steering, which limits their application inside narrower organs. Herein, we present a novel endoscopic image-guided laser treatment system with a thin tip that can access inside narrow organs. The system uses a single fiber bundle to simultaneously acquire endoscopic images and modulate the laser-irradiated area. The insertion and operation of the system in a narrow space were demonstrated using an artificial vascular model. Repeated laser steering along set targets demonstrated accurate laser irradiation within a root-mean-square error of 28 [Formula: see text]m, and static repeatability such that the laser irradiation position was controlled within a 12 [Formula: see text]m radius of dispersion about the mean trajectory. Unexpected irradiation on the distal irradiated plane due to fiber bundle crosstalk was reduced by selecting the appropriate laser input diameter. The laser steering trajectory spatially controlled the photothermal effects, vaporization, and coagulation of chicken liver tissue. This novel system achieves minimally invasive endoscopic laser treatment with high lesion-selectivity in narrow organs, such as the peripheral lung and coronary arteries.

Influence of Artificial Intelligence on the Adenoma Detection Rate throughout the Day

BACKGROUND

Artificial intelligence systems recently demonstrated an increase in polyp and adenoma detection rate. Over the daytime, the adenoma detection rate decreases as tiredness leads to a lack of attention. It is not clear if a polyp detection system with artificial intelligence leads to constant adenoma detection over the day.

METHODS

We performed a database analysis of screening and surveillance colonoscopies with and without the use of AI. In both groups, patients were investigated with the same endoscopy equipment and by the same endoscopists. Only patients with good bowel preparation (BBPS >6) were included. We correlated the daytime, the investigational time, day of the week, and the adenoma and polyp detection.

RESULTS

A total of 303 colonoscopies were analyzed. 163 endoscopies in the AI+ group and 140 procedures in the AI- group were included. In both groups, the total adenoma detection rate was equal (AI+ 0.39 vs. AI- 0.43). The adenoma detection rate throughout the day had a significant decreasing trend in the group without the use of AI (p = 0.015), whereas this trend was not present in the investigations that have been performed with AI (p = 0.65). The duration of investigation did not show a significant difference between the groups (8.9 min in both groups). No relevant effect was noticed in adenoma detection between single days of the working week with or without the use of AI.

CONCLUSION

AI helps overcome the decay in adenoma detection over the daytime. This may be attributed to a constant awareness caused by the use of the AI system.

Trial protocol for COLO-DETECT: A randomized controlled trial of lesion detection comparing colonoscopy assisted by the GI Genius™ artificial intelligence endoscopy module with standard colonoscopy

AIM

Colorectal cancer is the second commonest cause of cancer death worldwide. Colonoscopy plays a key role in the control of colorectal cancer and, in that regard, maximizing detection (and removal) of pre-cancerous adenomas at colonoscopy is imperative. GI Genius™ (Medtronic Ltd) is a computer-aided detection system that integrates with existing endoscopy systems and improves adenoma detection during colonoscopy. COLO-DETECT aims to assess the clinical and cost effectiveness of GI Genius™ in UK routine colonoscopy practice.

METHODS AND ANALYSIS

Participants will be recruited from patients attending for colonoscopy at National Health Service sites in England, for clinical symptoms, surveillance or within the national Bowel Cancer Screening Programme. Randomization will involve a 1:1 allocation ratio (GI Genius™-assisted colonoscopy:standard colonoscopy) and will be stratified by age category (<60 years, 60-<74 years, ≥74 years), sex, hospital site and indication for colonoscopy. Demographic data, procedural data, histology and post-procedure patient experience and quality of life will be recorded. COLO-DETECT is designed and powered to detect clinically meaningful differences in mean adenomas per procedure and adenoma detection rate between GI Genius™-assisted colonoscopy and standard colonoscopy groups. The study will close when 1828 participants have had a complete colonoscopy. An economic evaluation will be conducted from the perspective of the National Health Service. A patient and public representative is contributing to all stages of the trial. Registered at ClinicalTrials.gov (NCT04723758) and ISRCTN (10451355). WHAT WILL THIS TRIAL ADD TO THE LITERATURE?: COLO-DETECT will be the first multi-centre randomized controlled trial evaluating GI Genius™ in real world colonoscopy practice and will, uniquely, evaluate both clinical and cost effectiveness.

Future of Endoscopy in Inflammatory Bowel Diseases (IBDs)

Gastrointestinal (GI) endoscopy has transformed over the years in scope, safety, accuracy, acceptability, and cost effectiveness of the clinical practice. There has been a reduction in the superiority of the endoscopic devices as innovations have taken place and increased the diagnostic values with certain limitations. There are particular difficulties in striking a balance between the development of new technology and the device's acceptance. The wide use of endoscopy for investigating GI lesions and diagnosis has led to an increase in more advanced methods and their broad application. It can simultaneously diagnose pre-malignant and malignant lesions, and newer interventions have made the biopsy specimen uptake possible. In this review article, we focus on the more recent roles, indications, applications, and usage of the innovative methods of endoscopy.

Adenoma detection rate using narrow-band imaging is inferior to high-definition white light colonoscopy in screening and surveillance colonoscopies in daily clinical care: A randomized controlled trial

BACKGROUND

Despite recent advances in endoscopic technology adenoma miss rate still is up to 20% contributing to interval cancers. Improved imaging modalities have been introduced to increase adenoma detection rate (ADR). Recently, narrow-band imaging (NBI) (Exera II series, Olympus Corporation) was not significantly better than high-definition white light colonoscopy (HD-WLC). An improved second generation of NBI (190-NBI) is characterized by better illumination of the bowel lumen and may be associated with a higher ADR.

METHODS

We performed a prospective randomized study on patients referred to the Jena University Hospital for screening or surveillance colonoscopy between January 2015 and April 2017. Participating endoscopists were divided into 2 subgroups depending on their individual experience. Colonoscopy was performed by use of HD-WLC or 190-NBI upon withdrawal.

RESULTS

Five hundred fifty-three patients participated in the study. Eighty patients were excluded (insufficient bowel cleansing [n = 34], anticoagulation precluding polypectomy [n=15], partial colonic resection [n=9], other reasons [n = 22]). Mean age was 66.9 years (standard deviation 10.3 years), and 253 patients were male (53.5%). Bowel preparation and withdrawal time were not different. ADR among all subgroups was 39.4% using HD-WLC, but only 29.1% were using 190-NBI (P = .02). Number of polyps per patient was lower using 190-NBI than with HD-WLC (0.58 vs 0.86; P = .02). Subgroup analysis revealed that 190-NBI was inferior to HD-WLC only in unexperienced endoscopists.

CONCLUSION

In our stud,y ADR was lower by use of 190-NBI. These differences persisted only in unexperienced investigators. 190-NBI seems to be more challenging regarding ADR, requiring more intensive training prior to implementing this technology in daily clinical care.

REGISTRATION

ClinicalTrials.gov (identifier: NCT03081975).

Detection of colorectal lesions during colonoscopy

Owing to its high mortality rate, the prevention of colorectal cancer is of particular importance. The resection of colorectal polyps is reported to drastically reduce colorectal cancer mortality, and examination by endoscopists who had a high adenoma detection rate was found to lower the risk of colorectal cancer, highlighting the importance of identifying lesions. Various devices, imaging techniques, and diagnostic tools aimed at reducing the rate of missed lesions have therefore been developed to improve detection. The distal attachments and devices for improving the endoscopic view angle are intended to help avoid missing blind spots such as folds and flexures in the colon, whereas the imaging techniques represented by image‐enhanced endoscopy contribute to improving lesion visibility. Recent advances in artificial intelligence‐supported detection systems are expected to supplement an endoscopist's eye through the instant diagnosis of the lesions displayed on the monitor. In this review, we provide an outline of each tool and assess its impact on the reduction in the incidence of missed colorectal polyps by summarizing previous clinical research and meta‐analyses. Although useful, the many devices, image‐enhanced endoscopy, and artificial intelligence tools exhibited various limitations. Integrating these tools can improve their shortcomings. Combining artificial intelligence‐based diagnoses with wide‐angle image‐enhanced endoscopy may be particularly useful. Thus, we hope that such tools will be available in the near future.

Advances in optical gastrointestinal endoscopy: a technical review

Optical endoscopy is the primary diagnostic and therapeutic tool for management of gastrointestinal (GI) malignancies. Most GI neoplasms arise from precancerous lesions; thus, technical innovations to improve detection and diagnosis of precancerous lesions and early cancers play a pivotal role in improving outcomes. Over the last few decades, the field of GI endoscopy has witnessed enormous and focused efforts to develop and translate accurate, user-friendly, and minimally invasive optical imaging modalities. From a technical point of view, a wide range of novel optical techniques is now available to probe different aspects of light-tissue interaction at macroscopic and microscopic scales, complementing white light endoscopy. Most of these new modalities have been successfully validated and translated to routine clinical practice. Herein, we provide a technical review of the current status of existing and promising new optical endoscopic imaging technologies for GI cancer screening and surveillance. We summarize the underlying principles of light-tissue interaction, the imaging performance at different scales, and highlight what is known about clinical applicability and effectiveness. Furthermore, we discuss recent discovery and translation of novel molecular probes that have shown promise to augment endoscopists' ability to diagnose GI lesions with high specificity. We also review and discuss the role and potential clinical integration of artificial intelligence-based algorithms to provide decision support in real time. Finally, we provide perspectives on future technology development and its potential to transform endoscopic GI cancer detection and diagnosis.

Will purposely seeking detect more colorectal polyps than routine performing during colonoscopy?

BACKGROUND & GOALS

We observed that the number of colorectal polyps found intraoperatively was often higher than that encountered preoperatively during elective colonoscopic polypectomy. To evaluate whether more polyps can be detected when they are purposely sought than when they are routinely examined during colonoscopy.

MATERIALS AND METHODS

Patients undergoing colonoscopy were randomized into groups A and B. Before colonoscopy was performed, endoscopists were instructed to seek polyps for group A purposely but not for group B. Polypectomy was electively completed. In groups A and B, the cases of elective polypectomy were named groups AR and BR, including groups AR-1 and BR-1, during the first colonoscopy and groups AR-2 and BR-2 during the second colonoscopy for polypectomy, respectively. The following data were calculated: the number of polyps detected (NPD) and the polyp detection rate (PDR) in all cases and the number of polyps missed (NPM) and partial polyp miss rate (PPMR) in the cases of colorectal polyps.

RESULTS

A total of 419 cases were included in group A, 421 in group B, 43 in group AR, and 35 in group BR. No significant differences in PDR were found between groups A and B and in PPMR between groups AR-1 and BR-1 (P > .05), although PPMR in group AR-1 was higher than in group AR-2 (P < .05), similar results were found in PPMR between groups BR-1 and BR-2 (P < .05).

CONCLUSION

Purposely seeking for colorectal polyps did not result in more polyps detected compared with routine colonoscopy.

The Use of Attachment Devices to Aid in Adenoma Detection

PURPOSE OF REVIEW

With the intent of maximizing adenoma detection rate (ADR), different devices and colonoscopic innovations have been introduced over the past few years. There are a variety of attachment devices available for use in colonoscopy, all intended to improve ADR. In this review, we evaluate the evidence surrounding the available attachment devices and their impact on ADR.

RECENT FINDINGS

Endocuff, Endoring, Transparent cap, G-EYE balloon, and Third Eye Retroscope were all included in this review. Three of the devices, Endocuff, Endoring, and transparent hood or cap, have been shown to increase ADR without significantly altering the use of the colonoscope. Although balloon-assisted colonoscopy is not currently FDA-approved, it has the potential to increase ADR as well.

SUMMARY

Mechanical enhancement has been shown to complement the current forward-viewing colonoscope, and Endocuff appears to be the most beneficial attachment to improve ADR.

Advances in endoscopy for colorectal polyp detection and classification

While colonoscopy is considered the gold standard for colon cancer screening, recent advancements in endoscopes have allowed for improved visualization of the colonic mucosa and improved polyp detection rates. Newer technologies also allow for assessment of structural changes for polyp discrimination and determination of histologic type. Classification of polyps prevents the need for a histopathologic report, which requires the additional time and expertise of a pathologist and adds to the overall cost. This review considered advances in endoscopic technologies reported in PubMed over the past 12 years. Technologies that allow for increased visual field of colonic mucosa and may lead to improved colon polyp detection rates include cap-assisted colonoscopy, RetroView, extra-wide-angle view colonoscope, full-spectrum endoscopy, Third Eye Retroscope, NaviAid G-EYE balloon colonoscope, EndoRings, and Endocuff. Image-enhancing methods allow for pit pattern analysis of colorectal lesions, which enables the physician to classify colorectal polyps according to certain polyp characteristics. Image-enhancing methods include chromoendoscopy, autofluorescence, and virtual chromoendoscopy, including narrow band imaging, i-SCAN, flexible spectral imaging chromoendoscopy, and STORZ professional image enhancement systems. In addition, advancements have been made in in vivo microscopic evaluation of colonic epithelium, including confocal laser endomicroscopy, endocytoscopy, optical coherence tomography, spectroscopy, and autofluorescence spectroscopy. Colon capsule endoscopy also has a role in colon polyp detection and classification. The advancements in polyp detection and classification have great promise for earlier detection and removal of advanced adenomas before they advance to colorectal cancer.

Optimizing Screening Colonoscopy: Strategies and Alternatives

Screening colonoscopy is the most effective screening procedure for the prevention of colorectal cancer. The efficacy of colonoscopy is highly dependent on the overall quality of how this procedure is indicated, planned, prepared, and performed. The quality is directly linked to the number of polyps and/or adenomas detected or, in other words, to the number of polyps or adenomas missed during the procedure. The quality has a direct impact on the rate of interval carcinoma and on the range of how the incidence and occurrence of colorectal cancer is reduced. This review summarizes the current status on general measures and procedure improvements and standards as well as technical advances which have been suggested and established to improve the quality of polyp and adenoma detection rate. This includes selection and preparation of the patients, planning, methodological and technical performance of the procedure, and technical advances of the endoscope technology in order to improve screening results. It also covers new technologies with wide angle endoscopes (Ewave) and IT-based approaches using artificial intelligence to such as ai4GI for the polyp detection and image analysis.

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.

Sessile Serrated Adenomas: How to Detect, Characterize and Resect

Serrated polyps are important contributors to the burden of colorectal cancers (CRC). These lesions were once considered to have no malignant potential, but currently up to 30% of all CRC are recognized to arise from the serrated neoplasia pathway. The primary premalignant lesions are sessile serrated adenomas/polyps (SSA/Ps), although traditional serrated adenomas are relatively uncommon. Compared to conventional adenomas, SSA/Ps are morphologically subtle with indistinct borders, may be difficult to detect endoscopically, are more prevalent than previously thought, are associated with synchronous and metachronous advanced neoplasia, and have a higher risk of incomplete resection. Although many lesions remain “dormant,” progressive disease is associated with the development of dysplasia and more rapid progression to CRC. As a result, SSA/Ps are strongly implicated in the development of interval cancers. These factors represent unique challenges that require a meticulous approach to their management. In this review, we summarize the contemporary literature on the characterization, detection and resection of SSA/Ps.

G-EYE advanced colonoscopy for improved polyp detection rates - a randomized tandem pilot study with different endoscopists

BACKGROUND AND AIMS

 The most commonly missed polyps in colonoscopy are those located behind haustral folds. The G-EYE system is a standard colonoscope consisting of re-processable balloon at its distal tip. The G-EYE balloon improves the detection of polyps by straightening the haustral folds. In our back-to-back tandem study, we aimed to determine whether and to what extent the G-EYE system could reduce adenoma miss rates in screening colonoscopy.

METHODS

 Patients referred to colonoscopy were randomized into 2 groups. Group A underwent a standard colonoscopy (SC) followed by balloon colonoscopy (BC), and Group B underwent BC followed by SC. In this randomized tandem study, the investigator's level of training and the endoscopists themselves were changed after each withdrawal. Each endoscopist was blinded to the results of the first withdrawal.

RESULTS

 Fifty-eight patients were enrolled and randomized into 2 groups with similar baseline characteristics. Nine patients were excluded from the study. Twenty-five patients underwent SC followed by BC while 24 underwent BC followed by SC. The adenoma miss rate for SC was 41 %, with an additional detection rate of 69 % for BC (ratio 1.69). The overall miss rate for polyps was 60 % for SC, with an additional detection rate of 150 % for BC (ratio 2.5). Experienced investigators who used BC were able to identify an additional 7 polyps while inexperienced investigators.

CONCLUSIONS

 Although our results could not clearly confirm that BC improves adenoma detection, the investigator's experience appears to be a major determinant of the adenoma detection rate.

Post-colonoscopy colorectal cancer rate in the era of high-definition colonoscopy

AIM

To investigate the post-colonoscopy colorectal cancer (PCCRC) rate for high-definition (HD) colonoscopy compared with that for standard-definition colonoscopy reported previously.

METHODS

Using medical records at Sano Hospital (SH) and Dokkyo Medical University Koshigaya Hospital (DMUKH), we retrospectively obtained data on consecutive patients diagnosed as having CRC between January 2010 and December 2015. The definition of PCCRC was diagnosis of CRC between 7 and 36 mo after initial high-definition colonoscopy that had detected no cancer, and patients were divided into a PCCRC group and a non-PCCRC group. The primary outcome was the rate of PCCRC for HD colonoscopy. The secondary outcomes were factors associated with PCCRC and possible reason for occurrence of early and advanced PCCRC.

RESULTS

Among 892 CRC patients, 11 were diagnosed as having PCCRC and 881 had non-PCCRC. The PCCRC rate was 1.7% (8/471) at SH and 0.7% (3/421) at DMUKH. In comparison with the non-PCCRC group, the PCCRC group had a significantly higher preponderance of smaller tumors (39 mm vs 19 mm, P = 0.002), a shallower invasion depth (T1 rate, 25.4% vs 63.6%, P = 0.01), a non-polypoid macroscopic appearance (39.0% vs 85.7%, P = 0.02) and an earlier stage (59.7% vs 90.9%, P = 0.03). Possible reasons for PCCRC were "missed or new" in 9 patients (82%), "incomplete resection" in 1 (9%), and "inadequate examination'" in 1 (9%). Among 9 "missed or new" PCCRC, the leading cause was non-polypoid shape for early PCCRC and blinded location for advanced PCCRC.

CONCLUSION

The PCCRC rate for HD colonoscopy was 0.7%-1.7%, being lower than that for standard-definition colonoscopy (1.8%-9.0%) reported previously employing the same methodology.

Clinical impact of surveillance colonoscopy using magnification without diminutive polyp removal

BACKGROUND AND AIM

In Western countries, endoscopic removal of all adenomas during colonoscopy is recommended. The present study evaluates the usefulness of magnifying colonoscopy without removal of diminutive (≤5 mm) colorectal polyps.

METHODS

Patients with diminutive polyps who were observed for over 5 years using magnification at Hiroshima University Hospital were selected retrospectively. Lesions ≥6 mm in size, depressed lesions, and lesions with type V pit pattern were indications for endoscopic resection. We investigated the characteristics of lesions indicated for endoscopic resection detected on surveillance colonoscopy and the risk factors for the incidence of lesions indicated for endoscopic resection.

RESULTS

A total of 706 consecutive patients were enrolled. Sixty-eight lesions indicated for endoscopic resection were detected, averaging 9.0 ± 4.8 mm, and 33 (49%) lesions were located in the right colon. Pathological diagnoses were adenoma, Tis carcinoma, and T1 carcinoma in 58 (85%), eight (12%), and two (3%) lesions, respectively. Five lesions were considered to grow from previously detected diminutive polyps. Relative risks for the incidence of a lesion indicated for endoscopic resection were 1.76 (95% confidence interval [CI], 1.004-3.23) for males compared with females, 3.76 (95% CI, 2.03-7.50) for more than three polyps at initial colonoscopy compared with one polyp, and 2.84 (95% CI, 1.43-5.24) for patients with carcinoma at initial colonoscopy compared with patients with no lesion indicated for endoscopic resection. Nine carcinomas were resected endoscopically.

CONCLUSION

Diminutive low-grade adenomas detected by using magnifying colonoscopy may not necessarily require removal.

Use of warm carbon dioxide insufflators does not affect intra-colonic gas temperature and has no effect on polyp detection rate during colonoscopy - a randomized controlled trial

BACKGROUND AND STUDY AIMS

Methods to improve polyp detection during colonoscopy have been investigated, with conflicting results for warm water irrigation. Carbon Dioxide (CO ₂₎ warmed to 37 °C may have similar or more pronounced effects on bowel motility. This study aimed to assess whether warmed CO ₂ would improve polyp detection compared to room temperature air insufflation.

PATIENTS AND METHODS

 This was a double-blind, randomized controlled trial that enrolled 204 patients undergoing screening or surveillance outpatient colonoscopy. The primary outcome was polyp per patient detection rate. Secondary outcomes included adenoma per patient detection rates, bowel spasm, and patient comfort.

RESULTS

 The trial was terminated after an interim analysis determined futility. Between the warmed CO ₂ and room air groups, no significant differences were found in the per-colonoscopy polyp detection rate ( P  = 0.57); overall polyp detection rate ( P  = 0.69); or adenoma detection rates ( P  = 0.74). More patients in the room temperature group had lower spasm scores (p = 0.02); however, there was a trend towards greater patient comfort in the warmed CO ₂ group ( P  = 0.054). An ex-vivo study showed a significant difference between exiting CO ₂ temperature at the insufflator end vs. delivered CO ₂ temperature at the colonoscope tip end. The temperature of insufflation at the tip of the colonoscope was not different when using warmed vs. unwarmed insufflation ( P  = 0.62).

CONCLUSION

 When compared with room air insufflation, warmed CO ₂ insufflation did not affect polyp detection rates.

A guide to multimodal endoscopy imaging for gastrointestinal malignancy - an early indicator

Multimodality imaging is an essential aspect of endoscopic surveillance for the detection of neoplastic lesions, such as dysplasia or intramucosal cancer, because it improves the efficacy of endoscopic surveillance and therapeutic procedures in the gastrointestinal tract. This approach reveals mucosal abnormalities that cannot be detected by standard endoscopy. Currently, these imaging techniques are divided into those for primary detection and those for targeted imaging and characterization, the latter being used to visualize areas of interest in detail and permit histological evaluation. This Review outlines the use of virtual chromoendoscopy, narrow-band imaging, autofluorescence imaging, optical coherence tomography, confocal endomicroscopy and volumetric laser endomicroscopy as new imaging techniques for diagnostic investigation of the gastrointestinal tract. Insights into use of multimodal endoscopic imaging for early disease detection, in particular for pre-malignant lesions, in the oesophagus, stomach and colon are described.

Enhanced flat adenoma detection rate with high definition colonoscopy plus i-scan for average-risk colorectal cancer screening

BACKGROUND AND AIM

The usefulness of high definition colonoscopy plus i-scan (HD+i-SCAN) for average-risk colorectal cancer screening has not been fully assessed. The detection rate of adenomas and other measurements such as the number of adenomas per colonoscopy and the flat adenoma detection rate have been recognized as markers of colonoscopy quality. The aim of the present study was to compare the diagnostic performance of an HD+i-SCAN with that of standard resolution white-light colonoscope.

METHODS

This is a retrospective analysis of a prospectively collected screening colonoscopy database. A comparative analysis of the diagnostic yield of an HD+i-SCAN or standard resolution colonoscopy for average-risk colorectal screening was conducted.

RESULTS

During the period of study, 155/163 (95.1%) patients met the inclusion criteria. The mean age was 56.9 years. Sixty of 155 (39%) colonoscopies were performed using a HD+i-SCAN. Adenoma-detection-rates during the withdrawal of the standard resolution versus HD+i-SCAN colonoscopies were 29.5% and 30% (p = n.s.). Adenoma/colonoscopy values for standard resolution versus HD+i-SCAN colonoscopies were 0.46 (SD = 0.9) and 0.72 (SD = 1.3) (p = n.s.). A greater number of flat adenomas were detected in the HD+i-SCAN group (6/60 versus 2/95) (p < .05). Likewise, serrated adenomas/polyps per colonoscopy were also higher in the HD+i-SCAN group.

CONCLUSIONS

A HD+i-SCAN colonoscopy increases the flat adenoma detection rate and serrated adenomas/polyps per colonoscopy compared to a standard colonoscopy in average-risk screening population. HD+i-SCAN is a simple, available procedure that can be helpful, even for experienced providers. The performance of HD+i-SCAN and substantial prevalence of flat lesions in our average-risk screening cohort support its usefulness in improving the efficacy of screening colonoscopies.

An Insect Eye Inspired Miniaturized Multi-Camera System for Endoscopic Imaging

In this work, we present a miniaturized high definition vision system inspired by insect eyes, with a distributed illumination method, which can work in dark environments for proximity imaging applications such as endoscopy. Our approach is based on modeling biological systems with off-the-shelf miniaturized cameras combined with digital circuit design for real time image processing. We built a 5 mm radius hemispherical compound eye, imaging a 180^°×180^° degrees field of view while providing more than 1.1 megapixels (emulated ommatidias) as real-time video with an inter-ommatidial angle ∆ϕ = 0.5^° at 18 mm radial distance. We made an FPGA implementation of the image processing system which is capable of generating 25 fps video with 1080 × 1080 pixel resolution at a 120 MHz processing clock frequency. When compared to similar size insect eye mimicking systems in literature, the system proposed in this paper features 1000 × resolution increase. To the best of our knowledge, this is the first time that a compound eye with built-in illumination idea is reported. We are offering our miniaturized imaging system for endoscopic applications like colonoscopy or laparoscopic surgery where there is a need for large field of view high definition imagery. For that purpose we tested our system inside a human colon model. We also present the resulting images and videos from the human colon model in this paper.

Flexible Gastro-intestinal Endoscopy - Clinical Challenges and Technical Achievements

Flexible gastro-intestinal (GI) endoscopy is an integral diagnostic and therapeutic tool in clinical gastroenterology. High quality standards for safety, patients' comfort, and efficiency have already been achieved. Clinical challenges and technical approaches are discussed in this short review.

Image enhanced endoscopy for further characterization of mucosal and vascular patterns includes dye-spray or virtual chromoendoscopy. For confocal laser endoscopy, endocytoscopy, and autofluorescence clinical value has not yet been finally evaluated. An extended viewing field provided by additional cameras in new endoscopes can augment detection of polyps behind folds. Attachable caps, flaps, or balloons can be used to flatten colonic folds for better visualization and stable position.

Variable stiffness endoscopes, radiation-free visualization of endoscope position, and different overtube devices help reducing painful loop formation in clinical routine. Computer assisted and super flexible self-propelled colonoscopes for painless sedation-free endoscopy need further research. Single-use devices might minimize the risk of infection transmission in the future.

Various exchangeable accessories are available for resection, dissection, tunneling, hemostasis, treatment of stenosis and closure of defects, including dedicated suturing devices. Multiple arm flexible devices controlled via robotic platforms for complex intraluminal and transmural endoscopic procedures require further improvement.

Technical interventions to increase adenoma detection rate in colonoscopy

Adenoma detection rate (ADR) is the most robust colonoscopy quality metric and clinical studies have adopted it as the ideal method to assess the impact of technical interventions. Areas covered: We reviewed papers focusing on the impact of colonoscopy technical issues on ADR, including withdrawal time and technique, second evaluation of the right colon, patient positional changes, gastrointestinal assistant participation during colonoscopy, water-aided technique, optimization of bowel preparation and antispasmodic administration. Expert commentary: Overall, technical interventions are inexpensive, available worldwide and easy to implement. Some of them, such as the adoption of split dose regimen and slow scope withdrawal to allow a careful inspection, have been demonstrated to significantly improve ADR. Emerging data support the use of water-exchange colonoscopy. According to published studies, other technical interventions seem to provide only marginal benefit to ADR. Unfortunately, the available evidence has methodological limitations, such as small sample sizes, the inclusion of expert endoscopists only and the evaluation of single technical interventions. Additionally, larger studies are needed to clarify whether these interventions might have a higher benefit on low adenoma detectors and whether the implementation of a bundle of them, instead of a single technical maneuver, might have a greater impact on ADR.

Enteroscopy and radiology for the management of celiac disease complications: Time for a pragmatic roadmap

Celiac disease is the most common autoimmune enteropathy in Western countries, and is usually associated with a good response to the gluten free diet and an excellent prognosis. However, a minority of patients develop complications of the disease, such as refractory celiac disease, ulcerative jejunoileitis and neoplastic complications such as adenocarcinoma of the small bowel and enteropathy associated T cell lymphoma. Neoplastic complications described in association with celiac disease have a high mortality rate, due to their aggressive behavior and to the usual advanced stage at the time of diagnosis. In recent years, the detection of small bowel lesions has dramatically improved thank to the availability of highly performing radiologic and endoscopic techniques. The diagnostic delay of malignant complications in patients with celiac disease may be improved by establishing a pragmatic flowchart for the identification and follow up of "at risk" patients. We performed a comprehensive review of the articles published on this issue in order to promote a roadmap to be applied when facing with celiac patients with suspected small bowel complications.

Endocuff-Assisted Colonoscopy-A Novel Accessory in Improving Adenoma Detection Rate: A Review of the Literature

Endocuff (Arc Medical Design) is a U.S. Food and Drug Administration-approved device that is attached like a cap to the distal tip of the colonoscope; it is used to improve adenoma detection rates during colonoscopy. The aim of this review was to summarize and evaluate the clinical and technical efficacy of Endocuff in improving adenoma detection rate. A comprehensive literature review was performed to identify studies describing this technique. In this review article, we have summarized case series and reports describing Endocuff use and results. The reported indications, results, limitations, and complications are discussed.

Frontiers of robotic endoscopic capsules: a review

Digestive diseases are a major burden for society and healthcare systems, and with an aging population, the importance of their effective management will become critical. Healthcare systems worldwide already struggle to insure quality and affordability of healthcare delivery and this will be a significant challenge in the midterm future. Wireless capsule endoscopy (WCE), introduced in 2000 by Given Imaging Ltd., is an example of disruptive technology and represents an attractive alternative to traditional diagnostic techniques. WCE overcomes conventional endoscopy enabling inspection of the digestive system without discomfort or the need for sedation. Thus, it has the advantage of encouraging patients to undergo gastrointestinal (GI) tract examinations and of facilitating mass screening programmes. With the integration of further capabilities based on microrobotics, e.g. active locomotion and embedded therapeutic modules, WCE could become the key-technology for GI diagnosis and treatment. This review presents a research update on WCE and describes the state-of-the-art of current endoscopic devices with a focus on research-oriented robotic capsule endoscopes enabled by microsystem technologies. The article also presents a visionary perspective on WCE potential for screening, diagnostic and therapeutic endoscopic procedures.

Feasibility of full-spectrum endoscopy: Korea’s first full-spectrum endoscopy colonoscopic trial

AIM: To evaluate the full-spectrum endoscopy (FUSE) colonoscopy system as the first report on the utility thereof in a Korean population.

METHODS: We explored the efficacy of the FUSE colonoscopy in a retrospective, single-center feasibility study performed between February 1 and July 20, 2015. A total of 262 subjects (age range: 22-80) underwent the FUSE colonoscopy for colorectal cancer screening, polyp surveillance, or diagnostic evaluation. The cecal intubation success rate, the polyp detection rate (PDR), the adenoma detection rate (ADR), and the diverticulum detection rate (DDR), were calculated. Also, the success rates of therapeutic interventions were evaluated with biopsy confirmation.

RESULTS: All patients completed the study and the success rates of cecal and terminal ileal intubation were 100% with the FUSE colonoscope; we found 313 polyps in 142 patients and 173 adenomas in 95. The overall PDR, ADR and DDR were 54.2%, 36.3%, and 25.2%, respectively, and were higher in males, and increased with age. The endoscopists and nurses involved considered that the full-spectrum colonoscope improved navigation and orientation within the colon. No colonoscopy was aborted because of colonoscope malfunction.

CONCLUSION: The FUSE colonoscopy yielded a higher PDR, ADR, DDR than did traditional colonoscopy, without therapeutic failure or complications, showing feasible, effective, and safe in this first Korean trial.

How to improve colon cancer screening rates

Colorectal carcinoma is a common cause of death throughout the world and may be prevented by routine control, which can detect precancerous neoplasms and early cancers before they undergo malignant transformation or metastasis. Three strategies may improve colon cancer screening rates: convince the population about the importance of undergoing a screening test; achieve higher efficacy in standard screening tests and make them more available to the community and develop new more sensitive and efficacious screening methods and make them available as routine tests. In this light, the present study seeks to review these three means through which to increase colon cancer screening rates.

Interval Colorectal Cancer After Colonoscopy: Exploring Explanations and Solutions

There is good evidence that colorectal cancer (CRC) screening has been successful at reducing both CRC incidence and death. Colonoscopy, utilized as either a primary screening tool or a follow-up exam when other screening tests are positive, has significantly contributed to these encouraging trends. However, it is well recognized that colonoscopy is not perfectly sensitive for the detection of neoplasia and that CRC can be diagnosed within a short interval following a colonoscopy that did not detect one. The literature surrounding these cases has rapidly expanded over the last decade. Specifically, studies aimed at understanding the frequency of these events and the likely explanations for their occurrence have been performed. This review will highlight current knowledge around the epidemiology of interval post colonoscopy CRC (PCCRC). The common explanations for these cancers including missed lesions, new lesions, and incompletely resected lesions will be reviewed and their contribution to interval PCCRC estimated. Finally, the relationship of these putative explanations to potential opportunities to prevent interval PCCRC will be explored. Current approaches to prevention largely center on consistent adherence to quality colonoscopy standards. Future approaches include advances in technology to better visualize the colon and adequately resect detected neoplasia. Finally, improvement in training as well as development of a culture of continuous quality improvement will be essential to maximize the benefits of colonoscopy in daily clinical practice.

Expanding the view of a standard colonoscope with the Third Eye® Panoramic™ cap

AIM: To evaluate a new imaging device for colonoscopy that adds two side viewing CMOS lenses, the Third Eye^® Panoramic™ cap.

METHODS: In this prospective observational feasibility study, 33 patients, 18 male and 15 female, underwent routine screening, surveillance or diagnostic colonoscopy with the new Third Eye^® Panoramic™ cap clipped on to the distal tip of a high definition Fuji EC530-LS Slim Colonoscope^®. All procedures were performed at the New York Presbyterian-Queens Endoscopy unit by two experienced endoscopists (Rubin M and Kim SH). Main outcome measurements included evaluation of the image quality of the Third Eye^® Panoramic™ cap, adenoma detection rate, cecal intubation rate, withdrawal time and total procedure time.

RESULTS: The Third Eye^® Panoramic™ cap enabled enhanced views without affecting the quality of the colonoscope’s image or its handling characteristics through the colon. Ileal intubation was accomplished in most cases, but was more challenging. The side view lenses detected polyps and diverticula hidden behind folds and in flexures not seen on the standard view. The side view lenses were easily cleaned utilizing an Endogator^® Irrigation Pump (Medivators, Minneapolis, MN, United States) by angling the scope tip against the mucosa while washing. The cecum was reached in all 33 patients. Mean cecal intubation time was 8.19 ± 2.17 min, mean withdrawal time was 10.15 ± 5.56 min and mean total procedure time was 20.31 ± 5.14 min. The overall adenoma detection rate was 44%.

CONCLUSION: The Third Eye^® Panoramic™ cap enables wide view colonoscopy with enhanced visualization utilizing standard forward view colonoscopes.

Value of screening endoscopy in evaluation of esophageal, gastric and colon cancers

Esophageal, gastric, and colorectal cancers are deadly diseases that continue to plague our world today. The value of screening endoscopy in evaluating these types of cancers is a critical area of discussion due to a potential reduction in morbidity and mortality. This article describes how to identify a good screening test and explains what are important criteria in the field of screening endoscopy. Furthermore, the current status and progress of screening endoscopy for esophageal, gastric, and colorectal cancer will be evaluated and discussed. Mass screening programs have not been implemented for esophageal and gastric carcinomas in those with average or low risk populations. However, studies of high-risk populations have found value and a cost-benefit in conducting screening endoscopy. Colorectal cancer, on the other hand, has had mass screening programs in place for many years due to the clear evidence of improved outcomes. As the role of endoscopy as a screening tool has continued to develop, newer technology and techniques have emerged to improve its utility. Many new image enhancement techniques and computer processing programs have shown promise and may have a significant role in the future of endoscopic screening. These developments are paving the way for improving the diagnostic and therapeutic capability of endoscopy in the field of gastroenterology.