A survey of colonoscopists with and without in-depth knowledge of water-aided colonoscopy.

BACKGROUND AND AIM: Endoscopy featured water-aided colonoscopy (WAC) as novel in the Innovation Forum in 2011. Gastrointestinal Endoscopy published a modified Delphi consensus review (MDCR) that supports WAC for clinical practice in 2021. We tested the hypothesis that experience was an important predictor of WAC use, either as water immersion (WI), water exchange (WE), or a combination of WI and WE. METHODS: A questionnaire was sent by email to the MDCR authors with an in-depth knowledge of WAC. They responded and also invited colleagues and trainees without in-depth knowledge to respond. Logistic regression analysis was used with the reasons for WAC use treated as the primary outcome. Reports related to WAC post MDCR were identified. RESULTS: Of 100 respondents, > 80% indicated willingness to adopt and modify practice to accommodate WAC. Higher adenoma detection rate (ADR) incentivized WE use. Procedure time slots ≤ 30 and > 30 min significantly predicted WI and WE use, respectively. Co-authors of the MDCR were significantly more likely to perform WAC (odds ratio [OR] = 7.5, P = 0.037). Unfamiliarity with (OR = 0.11, P = 0.02) and absence of good experience (OR = 0.019, P = 0.002) were associated with colonoscopists less likely to perform WAC. Reports related to WAC post MDCR revealed overall and right colon WE outcomes continued to improve. Network meta-analyses showed that WE was superior to Cap and Endocuff. On-demand sedation with WE shortened nursing recovery time. CONCLUSIONS: An important predictor of WAC use was experience. Superior outcomes continued to be reported with WE.

Artificial Intelligence for Colonoscopy: Past, Present, and Future.

During the past decades, many automated image analysis methods have been developed for colonoscopy. Real-time implementation of the most promising methods during colonoscopy has been tested in clinical trials, including several recent multi-center studies. All trials have shown results that may contribute to prevention of colorectal cancer. We summarize the past and present development of colonoscopy video analysis methods, focusing on two categories of artificial intelligence (AI) technologies used in clinical trials. These are (1) analysis and feedback for improving colonoscopy quality and (2) detection of abnormalities. Our survey includes methods that use traditional machine learning algorithms on carefully designed hand-crafted features as well as recent deep-learning methods. Lastly, we present the gap between current state-of-the-art technology and desirable clinical features and conclude with future directions of endoscopic AI technology development that will bridge the current gap.

Muons, mutations, and planetary shielding.

Life on earth is protected from astrophysical cosmic rays by the heliospheric magnetic and slowly varying geomagnetic fields, and by collisions with oxygen and nitrogen molecules in the atmosphere. The collisions generate showers of particles of lesser energy; only muons, a charged particle with a mass between that of an electron and a proton, can reach earth's surface in substantial quantities. Muons are easily detected, used to image interior spaces of pyramids, and known to limit the stability of qubits in quantum computing; yet, despite their charge, average energy of 4 GeV and ionizing properties, muons are not considered to affect chemical reactions or biology. In this Perspective the potential damaging effects of muons on DNA, and hence the repercussions for evolution and disease, are examined. It is argued here that the effect of muons on life through DNA mutations should be considered when investigating the protection provided by the magnetic environment and atmosphere from cosmic rays on earth and exoplanets.

Colorectal cancer prevention by a CLEAR principles-based colonoscopy protocol: an observational study.

BACKGROUND AND AIMS: Colorectal cancer (CRC) prevention by colonoscopy has been lower than expected. We studied CRC prevention outcomes of a colonoscopy protocol based on Clean the colon, Look Everywhere, and complete Abnormality Removal (CLEAR) principles. METHODS: This observational follow-up study studied patients provided screening colonoscopy at a free-standing private ambulatory surgery center in South Carolina by 80 endoscopists from October 2001 to December 2014, followed through December 2015. The colonoscopy protocol, optimized for polyp clearance, featured in-person bowel preparation instructions reinforced by phone, polyp search and removal throughout insertion and gradual withdrawal with circumferential tip movements, and a team approach using all personnel present to maximize polyp detection, patient safety, and clear-margin polypectomy including requesting repeat inspection or additional tissue removal. Outcome measures were postscreening lifetime CRC risk relative to Surveillance Epidemiology and End Results (SEER)-18 and interval cancer rate (postcolonoscopy CRCs among cancer-free patients at screening). RESULTS: Of 25,862 patients (mean age, 58.1 years; 52% black; 205,522 person-years of observation), 159 had CRC at screening and 67 patients developed interval CRC. The interval CRC rate was 3.34 per 10,000 person-years of observation, 5.79 and 2.24 among patients with and without adenomas, respectively. The rate was similar among older patients (mean age 68.5 years at screening) and with prolonged follow-up. Postscreening lifetime CRC risk was 1.6% (bootstrap 95% confidence interval, 1.3%-1.8%) versus 4.7% in SEER-18, 67% lower. Subgroups with mean screening ages of 50 and 68.5 years showed risk reductions of 80% and 72%, respectively. The adverse event rate was less than usually reported rates: perforation 2.6 per 10,000, bleeding with hospitalization 2.4 per 10,000, and no deaths. CONCLUSIONS: A colonoscopy protocol optimized for polyp clearance prevented 67% of CRC compared with a SEER-18 population given ongoing population screening.

Simulation Research in Gastrointestinal and Urologic Care-Challenges and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases and National Institute of Biomedical Imaging and Bioengineering Workshop.

: A workshop on "Simulation Research in Gastrointestinal and Urologic Care: Challenges and Opportunities" was held at the National Institutes of Health in June 2016. The purpose of the workshop was to examine the extent to which simulation approaches have been used by skilled proceduralists (not trainees) caring for patients with gastrointestinal and urologic diseases. The current status of research findings in the use and effectiveness of simulation applications was reviewed, and numerous knowledge gaps and research needs were identified by the faculty and the attendees. The paradigm of "deliberate practice," rather than mere repetition, and the value of coaching by experts was stressed by those who have adopted simulation in music and sports. Models that are most useful for the adoption of simulation by expert clinicians have yet to be fully validated. Initial studies on the impact of simulation on safety and error reduction have demonstrated its value in the training domain, but the role of simulation as a strategy for increased procedural safety remains uncertain in the world of the expert practitioner. Although the basic requirements for experienced physicians to acquire new skills have been explored, the widespread availability of such resources is an unrealized goal, and there is a need for well-designed outcome studies to establish the role of simulation in improving the quality of health care.

Persisting Racial Disparities in Colonoscopy Screening of Persons with a Family History of Colorectal Cancer.

With 23 and 47% higher colorectal cancer (CRC) incidence and mortality, respectively, among African Americans vs. Whites, CRC screening studies are important. Screening guidelines recommend 5-yearly colonoscopy screening of persons with a family history of CRC (first-degree relatives, FDRs), beginning at 40 years of age. For this elevated-risk group, colonoscopy screening is preferred because of the risk of more aggressive cancer that may elude early detection by other methods. African Americans with a family history of CRC are at the intersection of two elevated risk demographics, race and FDR status. This study explored racial disparities in colonoscopy screening of FDRs using 2005, 2010, and 2015 national survey data on 3220 Whites and 466 African Americans.Despite increasing colonoscopy rates among FDRs (72.3 and 62.2% in 2015 among Whites and African Americans, respectively), the 40-49 age group showed substantial racial disparities each year, persisting through 2015 (58.8, 31.7, and 35.3% lower among African Americans in 2005, 2010, and 2015, respectively). Adjusted analysis of the pooled 3-year sample showed that FDRs aged 40-49 years had one-third the colonoscopy likelihood of the 50-plus age group. African Americans without college education were 40 and 60% less likely than Whites without college and with college education, respectively, to have had a colonoscopy. The sustained, high screening disparity, and low colonoscopy rates in the 40-49 age group overall, call for novel approaches to reduce CRC mortality disparities, such as, patient navigation programs to reach out to younger FDRs, particularly, less educated African Americans.

Simulation Research in Gastrointestinal and Urologic Care-Challenges and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases and National Institute of Biomedical Imaging and Bioengineering Workshop.

A workshop on ''Simulation Research in Gastrointestinal and Urologic Care: Challenges and Opportunities'' was held at the National Institutes of Health in June 2016. The purpose of the workshop was to examine the extent to which simulation approaches have been used by skilled proceduralists (not trainees) caring for patients with gastrointestinal and urologic diseases. The current status of research findings in the use and effectiveness of simulation applications was reviewed, and numerous knowledge gaps and research needs were identified by the faculty and the attendees. The paradigm of ''deliberate practice,'' rather than mere repetition, and the value of coaching by experts was stressed by those who have adopted simulation in music and sports. Models that are most useful for the adoption of simulation by expert clinicians have yet to be fully validated. Initial studies on the impact of simulation on safety and error reduction have demonstrated its value in the training domain, but the role of simulation as a strategy for increased procedural safety remains uncertain in the world of the expert practitioner. Although the basic requirements for experienced physicians to acquire new skills have been explored, the widespread availability of such resources is an unrealized goal, and there is a need for well-designed outcome studies to establish the role of simulation in improving the quality of health care.

Editorial: Polyps, Pain, and Propofol: Is Water Exchange the Panacea for All?

Water exchange (WE) is a relatively new method of endoscope insertion during colonoscopy. Although its origin is rooted in the insertion phase of colonoscopy, allowing the procedure to proceed with more ease, less discomfort, and less or no sedation, its most important value may reside in the withdrawal phase. In this issue, a randomized, prospective study from China specifically designed to examine the effect of WE on adenoma detection rate (ADR) confirms previous findings: WE improves ADR. Here we discuss the trial results, the benefits of WE, and the challenges that may preclude or delay widespread WE implementation.

Polyp-Alert: near real-time feedback during colonoscopy.

We present a software system called "Polyp-Alert" to assist the endoscopist find polyps by providing visual feedback during colonoscopy. Polyp-Alert employs our previous edge-cross-section visual features and a rule-based classifier to detect a polyp edge-an edge along the contour of a polyp. The technique employs tracking of detected polyp edge(s) to group a sequence of images covering the same polyp(s) as one polyp shot. In our experiments, the software correctly detected 97.7% (42 of 43) of polyp shots on 53 randomly selected video files of entire colonoscopy procedures. However, Polyp-Alert incorrectly marked only 4.3% of a full-length colonoscopy procedure as showing a polyp when they do not. The test data set consists of about 18 h worth of video data from Olympus and Fujinon endoscopes. The technique is extensible to other brands of colonoscopes. Furthermore, Polyp-Alert can provide as high as ten feedbacks per second for a smooth display of feedback. The performance of our system is by far the most promising to potentially assist the endoscopist find more polyps in clinical practice during a routine screening colonoscopy.

Colonoscopy screening among US adults aged 40 or older with a family history of colorectal cancer.

INTRODUCTION: Colonoscopy screening reduces colorectal cancer (CRC) incidence and mortality. CRC screening is recommended at age 50 for average-risk people. Screening of first-degree relatives of CRC patients is recommended to begin at age 40 or 10 years before the age at diagnosis of the youngest relative diagnosed with CRC. CRC incidence has increased recently among younger Americans while it has declined among older Americans. The objective of this study was to determine whether first-degree relatives of CRC patients are being screened according to recommended guidelines. METHODS: We studied colonoscopy screening rates among the US population reporting a CRC family history using 2005 and 2010 National Health Interview Survey data. RESULTS: Of 26,064 study-eligible respondents, 2,470 reported a CRC family history; of those with a family history, 45.6% had a colonoscopy (25.2% in 2005 and 65.8% 2010). The colonoscopy rate among first-degree relatives aged 40 to 49 in 2010 (38.3%) was about half that of first-degree relatives aged 50 or older (69.7%). First-degree relatives were nearly twice as likely as nonfirst-degree relatives to have a colonoscopy (adjusted odds ratio [AOR], 1.7; 95% confidence interval, 1.5-1.9), but those aged 40 to 49 were less likely to have a colonoscopy than those in older age groups (AOR, 2.6 for age 50-64; AOR, 3.6 for age ≥65). Interactions with age, insurance, and race/ethnicity were not significant. Having health insurance tripled the likelihood of screening. CONCLUSION: Despite a 5-fold increase in colonoscopy screening rates since 2005, rates among first-degree relatives younger than the conventional screening age have lagged. Screening promotion targeted to this group may halt the recent rising trend of CRC among younger Americans.

Colorectal cancer prevention by an optimized colonoscopy protocol in routine practice.

We conducted a retrospective cohort study to investigate the colorectal cancer (CRC) incidence and mortality prevention achievable in clinical practice with an optimized colonoscopy protocol targeting near-complete polyp clearance. The protocol consisted of: (i) telephonic reinforcement of bowel preparation instructions; (ii) active inspection for polyps throughout insertion and circumferential withdrawal; and (iii) timely updating of the protocol and documentation to incorporate the latest guidelines. Of 17,312 patients provided screening colonoscopies by 59 endoscopists in South Carolina, USA from September 2001 through December 2008, 997 were excluded using accepted exclusion criteria. Data on 16,315 patients were merged with the South Carolina Central Cancer Registry and Vital Records Registry data from January 1996 to December 2009 to identify incident CRC cases and deaths, incident lung cancers and brain cancer deaths (comparison control cancers). The standardized incidence ratios (SIR) and standardized mortality ratios (SMR) relative to South Carolina and US SEER-18 population rates were calculated. Over 78,375 person-years of observation, 18 patients developed CRC versus 104.11 expected for an SIR of 0.17, or 83% CRC protection, the rates being 68% and 91%, respectively among the adenoma- and adenoma-free subgroups (all p < 0.001). Restricting the cohort to ensure minimum 5-year follow-up (mean follow-up 6.64 years) did not change the results. The CRC mortality reduction was 89% (p < 0.001; four CRC deaths vs. 35.95 expected). The lung cancer SIR was 0.96 (p = 0.67), and brain cancer SMR was 0.92 (p = 0.35). Over 80% reduction in CRC incidence and mortality is achievable in routine practice by implementing key colonoscopy principles targeting near-complete polyp clearance.

Abnormal Image Detection in Endoscopy Videos Using a Filter Bank and Local Binary Patterns.

Finding mucosal abnormalities (e.g., erythema, blood, ulcer, erosion, and polyp) is one of the most essential tasks during endoscopy video review. Since these abnormalities typically appear in a small number of frames (around 5% of the total frame number), automated detection of frames with an abnormality can save physician's time significantly. In this paper, we propose a new multi-texture analysis method that effectively discerns images showing mucosal abnormalities from the ones without any abnormality since most abnormalities in endoscopy images have textures that are clearly distinguishable from normal textures using an advanced image texture analysis method. The method uses a "texton histogram" of an image block as features. The histogram captures the distribution of different "textons" representing various textures in an endoscopy image. The textons are representative response vectors of an application of a combination of Leung and Malik (LM) filter bank (i.e., a set of image filters) and a set of Local Binary Patterns on the image. Our experimental results indicate that the proposed method achieves 92% recall and 91.8% specificity on wireless capsule endoscopy (WCE) images and 91% recall and 90.8% specificity on colonoscopy images.

Part-based multiderivative edge cross-sectional profiles for polyp detection in colonoscopy.

This paper presents a novel technique for automated detection of protruding polyps in colonoscopy images using edge cross-section profiles (ECSP). We propose a part-based multiderivative ECSP that computes derivative functions of an edge cross-section profile and segments each of these profiles into parts. Therefore, we can model or extract features suitable for each part. Our features obtained from the parts can effectively describe complex properties of protruding polyps including the shape of the parts, texture, and protrusion and smoothness of the polyp surface. We evaluated our method against two existing polyp image detection techniques on 42 different polyps, including those with little protrusion. Each polyp has a large variation of appearance in viewing angles, light conditions, and scales in different images. The evaluation showed that our technique outperformed the existing techniques in both accuracy and analysis time. Our method has a higher area under the free-response receiver operating characteristic curve. For instance, when both techniques have a true positive rate for polyp image detection of 81.4%, the average number of false regions per image of our technique is 0.32 compared to 1.8 of the best existing technique under study. Additionally, our technique can precisely mark edges of candidate polyp regions as visual feedback. These results altogether indicate that our technique is promising to provide visual feedback of polyp regions in clinical practice.

3D Reconstruction of virtual colon structures from colonoscopy images.

This paper presents the first fully automated reconstruction technique of 3D virtual colon segments from individual colonoscopy images. It is the basis of new software applications that may offer great benefits for improving quality of care for colonoscopy patients. For example, a 3D map of the areas inspected and uninspected during colonoscopy can be shown on request of the endoscopist during the procedure. The endoscopist may revisit the suggested uninspected areas to reduce the chance of missing polyps that reside in these areas. The percentage of the colon surface seen by the endoscopist can be used as a coarse objective indicator of the quality of the procedure. The derived virtual colon models can be stored for post-procedure training of new endoscopists to teach navigation techniques that result in a higher level of procedure quality. Our technique does not require a prior CT scan of the colon or any global positioning device. Our experiments on endoscopy images of an Olympus synthetic colon model reveal encouraging results with small average reconstruction errors (4.1 mm for the fold depths and 12.1 mm for the fold circumferences).

Temporal Annotation in the Clinical Domain.

This article discusses the requirements of a formal specification for the annotation of temporal information in clinical narratives. We discuss the implementation and extension of ISO-TimeML for annotating a corpus of clinical notes, known as the THYME corpus. To reflect the information task and the heavily inference-based reasoning demands in the domain, a new annotation guideline has been developed, "the THYME Guidelines to ISO-TimeML (THYME-TimeML)". To clarify what relations merit annotation, we distinguish between linguistically-derived and inferentially-derived temporal orderings in the text. We also apply a top performing TempEval 2013 system against this new resource to measure the difficulty of adapting systems to the clinical domain. The corpus is available to the community and has been proposed for use in a SemEval 2015 task.