Colonoscopy Training Research Articles

Colonoscopy Direct Observation of Procedural Skills Assessment Tool for Evaluating Competency Development During Training.

Formative colonoscopy direct observation of procedural skills (DOPS) assessments were updated in 2016 and incorporated into UK training but lack validity evidence. We aimed to appraise the validity of DOPS assessments, benchmark performance, and evaluate competency development during training in diagnostic colonoscopy. This prospective national study identified colonoscopy DOPS submitted over an 18-month period to the UK training e-portfolio. Generalizability analyses were conducted to evaluate internal structure validity and reliability. Benchmarking was performed using receiver operator characteristic analyses. Learning curves for DOPS items and domains were studied, and multivariable analyses were performed to identify predictors of DOPS competency. Across 279 training units, 10,749 DOPS submitted for 1,199 trainees were analyzed. The acceptable reliability threshold (G > 0.70) was achieved with 3 assessors performing 2 DOPS each. DOPS competency rates correlated with the unassisted caecal intubation rate (rho 0.404, P < 0.001). Demonstrating competency in 90% of assessed items provided optimal sensitivity (90.2%) and specificity (87.2%) for benchmarking overall DOPS competence. This threshold was attained in the following order: "preprocedure" (50-99 procedures), "endoscopic nontechnical skills" and "postprocedure" (150-199), "management" (200-249), and "procedure" (250-299) domain. At item level, competency in "proactive problem solving" (rho 0.787) and "loop management" (rho 0.780) correlated strongest with the overall DOPS rating (P < 0.001) and was the last to develop. Lifetime procedure count, DOPS count, trainer specialty, easier case difficulty, and higher cecal intubation rate were significant multivariable predictors of DOPS competence. This study establishes milestones for competency acquisition during colonoscopy training and provides novel validity and reliability evidence to support colonoscopy DOPS as a competency assessment tool.

264 The Differences in Prevalence, Distribution, and Detection Rates of Colonic Polyps Between Genders

INTRODUCTION: Gender disparities in colorectal cancer (CRC) incidence and mortality are well recognized in the literature with polyp characteristics and location being amongst some of the most important factors contributing to these disparities. Prior studies have shown an increased prevalence of proximal adenomas and CRC in women. We aimed in this study to compare the distribution and the prevalence of colonic polyps between both genders, as well as evaluating gender-specific lesion detection rates. METHODS: A retrospective review of all screening colonoscopies in patients ≥50 years of age performed at our center between 2012 and 2014 was done. Average risk patients who had a complete colonoscopy with excellent, good and fair bowel preparation were included. Overall, gender-specific, and segment-specific adenoma detection rates (ADR), sessile serrated polyp detection rates (SSPDR) and polypectomy rates (PR) were calculated and compared using t-tests. Proximal colon was defined as the cecum, ascending, and the transverse colon. RESULTS: A total of 4151 patients were included in the analysis. Average patient age was 60.0 ± 7.7 years and 53.2% were females. A total of 652 (15.7%) had excellent preparation, 2675 (64.4%) had good preparation, while 824 (19.9%) had fair preparation (Table 1). Of the 3476 polyps found, 1660 (47%) polyps were found in the proximal colon. Generally, males had more polyps and adenomas all throughout the colon (Table 2). Compared to males, females had less proximal polyps per patient (0.35 ± 0.24 vs. 0.50 ± 0.33; P &lt; 0.001), less proximal adenomas per patient (0.22 ± 0.18 vs. 0.35 ± 0.26, P &lt; 0.001), and less overall large adenomas (&gt;1 cm) per patient (0.05 ± 0.07 vs. 0.09 ± 0.13, P &lt; 0.008). In males, endoscopists had better overall ADR (32.7 ± 14.7 vs. 22.0 ± 12.7, P &lt; 0.001), PR (51.9 ± 17.9 vs. 40.3 ± 18.8, P &lt; 0.001), and SSPDR (22.6 ± 15.7 vs. 16.6 ± 13.7, P &lt; 0.001) (Table 3). CONCLUSION: Our study demonstrates a significant difference in polyp distribution based on patient sex. This is contradictory to what has previously been reported in the literature with more proximal polyps noted in female patients. We believe the advancement in colonoscopy techniques and training in addition to the increased awareness of female sex association with right-sided tumors contributed to this topographic distribution shift of colonic polyps. Although the involved endoscopists met the recommended national ADR benchmarks, women had lower ADR reflecting the differences in the adenoma prevalence in these populations.

263 Male Gastroenterologists Have Better High-Risk Adenoma Detection Rate (HRADR) in Male Patients

INTRODUCTION: High-risk adenomas (HRA) have been associated with a significant risk of interval colorectal cancer development. Recent literature suggests that high-risk adenoma detection rate (HRADR) can be used as a complementary screening colonoscopy quality metric. Being dependent upon the experience- and skill-level of the provider, we aimed in this study to investigate the impact of gastroenterologists' gender on HRADR among screened patients. METHODS: A retrospective review of all screening colonoscopies in patients ≥50 years of age performed at our center between 2012 and 2014 was done. Average risk patients who had a complete colonoscopy with excellent, good, and fair bowel preparation were included. Overall, gender-specific, and segment-specific adenoma detection rates (ADR), large adenoma detection rate and high-risk adenoma detection rates (HRADR) were calculated and compared using t-tests. HRADR defined as either ≥3 adenomas or at least one adenoma of ≥10 mm (big adenoma) or at least one tubule-villous adenoma, high grade dysplasia or cancerous polyp. RESULTS: A total of 2641 patients were included in the analysis. Average patient age was 58 ± 7.6 years and 53.2% were females (Table 1). Compared to female gastroenterologists, male gastroenterologists had better overall HRADR (9.8 ± 6.6 vs. 5.0 ± 4.0; P &lt; 0.012) and overall Distal HRADR (4.6 ± 5.0 vs. 1.2 ± 2.2, 0.019). In male patients, male gastroenterologists had better proximal and distal HRADR (6.4 ± 7.0 vs. 1.8 ± 2.7; P &lt; 0.021 and 6.3 ± 7.4 vs. 1.2 ± 3; P &lt; 0.016, respectively). In female patients there was a non-significant trend toward better overall and segment-specific HRADR (P-value = 0.97, 0.56 and 0.30). Also, male gastroenterologists were better at detecting large adenomas (&gt;1 cm) in male patients (7.4 ± 8.3 vs.1.7 ± 3.3; P &lt; 0.016). All endoscopists met the nationally recommended ADR thresholds (25% overall, 20% for females and 30% for males). CONCLUSION: In this study, male gastroenterologists had better overall HRADR and overall Distal HRADR among all screened patients. In male patients, male gastroenterologists had better proximal and distal HRADR and were better at detecting large adenomas. This association was consistent across patient age, race, and level of colon preparation. These findings suggest that the differences in screening colonoscopy training and/or volume between male and female gastroenterologists may have important clinical implications in the detection of colon cancer and patient outcomes.

Challenges Facing the Detection of Colonic Polyps: What Can Deep Learning Do?

Colorectal cancer (CRC) is one of the most common causes of cancer mortality in the world. The incidence is related to increases with age and western dietary habits. Early detection through screening by colonoscopy has been proven to effectively reduce disease-related mortality. Currently, it is generally accepted that most colorectal cancers originate from adenomas. This is known as the “adenoma–carcinoma sequence”, and several studies have shown that early detection and removal of adenomas can effectively prevent the development of colorectal cancer. The other two pathways for CRC development are the Lynch syndrome pathway and the sessile serrated pathway. The adenoma detection rate is an established indicator of a colonoscopy’s quality. A 1% increase in the adenoma detection rate has been associated with a 3% decrease in interval CRC incidence. However, several factors may affect the adenoma detection rate during a colonoscopy, and techniques to address these factors have been thoroughly discussed in the literature. Interestingly, despite the use of these techniques in colonoscopy training programs and the introduction of quality measures in colonoscopy, the adenoma detection rate varies widely. Considering these limitations, initiatives that use deep learning, particularly convolutional neural networks (CNNs), to detect cancerous lesions and colonic polyps have been introduced. The CNN architecture seems to offer several advantages in this field, including polyp classification, detection, and segmentation, polyp tracking, and an increase in the rate of accurate diagnosis. Given the challenges in the detection of colon cancer affecting the ascending (proximal) colon, which is more common in women aged over 65 years old and is responsible for the higher mortality of these patients, one of the questions that remains to be answered is whether CNNs can help to maximize the CRC detection rate in proximal versus distal colon in relation to a gender distribution. This review discusses the current challenges facing CRC screening and training programs, quality measures in colonoscopy, and the role of CNNs in increasing the detection rate of colonic polyps and early cancerous lesions.

Significant Variation in the Detection Rates of Proximal Serrated Polyps Among Academic Gastroenterologists, Community Gastroenterologists, and Colorectal Surgeons in a Single Tertiary Care Center.

Recent studies have demonstrated that the protective effect of colonoscopy against colorectal cancer is lower in the proximal colon. Proximal serrated polyps, including sessile serrated adenomas and proximal hyperplastic polyps, can be frequently missed and pose a risk of interval cancers. To investigate the overall adenoma detection rate (ADR) and the proximal serrated polyp detection rate (PSPDR) among academic gastroenterologists, community gastroenterologists, and colorectal surgeons from a single institution, all of whom have received formal training in colonoscopy during their fellowship. All complete screening colonoscopies for patients aged 50 or older with a good to excellent bowel preparation performed by different endoscopists at Medstar Washington Hospital Center (Washington, DC) from July 2015 to December 2017 were reviewed. Pathology reports of the resected polyps were manually reviewed. A total of 2850 screening colonoscopies meeting the inclusion criteria were performed by 18 endoscopists (6 academic, 7 community, and 5 colorectal surgeons). There was no significant difference in the mean ADR among the three groups of endoscopists: academic gastroenterologists, community gastroenterologists, and colorectal surgeons (40.3% vs 36.0% vs 39.6%, respectively). However, academic gastroenterologists had a significantly higher PSPDR compared to community gastroenterologists or colorectal surgeons (12.3% vs 5.4% vs 4.5%, respectively, ANOVA p = 0.006). Our novel data show that academic gastroenterologists had a significantly higher PSPDR compared to community gastroenterologists or colorectal surgeons despite a comparable overall ADR among the three groups. PSPDR may be considered as an important quality indicator for colonoscopy, apart from ADR.

Tu1029 – Impact of Specific Teaching Strategies on Fellow Cognitive Load During Colonoscopy Training

Tu1029 – Impact of Specific Teaching Strategies on Fellow Cognitive Load During Colonoscopy Training

Colonoscopy utilization in rural areas by general surgeons: An analysis of the National Ambulatory Medical Care Survey

BackgroundOne in three adults above 50 years old have not been screened for colorectal cancer as of 2013.1 Rural areas have even lower screening and have more general surgeons compared to gastroenterologists,2 offering surgeons as a reservoir for necessary services. MethodsPublic data from the 2006–2015 CDC National Ambulatory Medical Care Survey was analyzed using SAS. Number of colonoscopies performed by rural general surgeons, family medicine practitioners, and other specialties were compared to their urban counterparts. Results21.91% of rural colonoscopies were performed by general surgeons, whereas 32.87% were performed by family medicine practitioners and 45.22% by other specialties including gastroenterologists. Rural general surgeons performed a greater percentage of annual rural colonoscopies than urban general surgeons (p < 0.05). ConclusionGeneral surgeons are fulfilling the need for colonoscopy in rural areas. Improvements to current colonoscopy training guidelines are imperative, especially for physicians who practice in rural areas.

Joint Advisory Group on Gastrointestinal Endoscopy (JAG) achieves enduring large-scale change

It is nearly 20 years since the national colonoscopy audit demonstrated poor performance of colonoscopy and inadequate training of colonoscopists.1 In 2004, a National Confidential Enquiry into Perioperative Deaths in...

Haptic feedback is useful in remote manipulation of flexible endoscopes.

Background and study aims We developed the Endoscopic Operation Robot (EOR) version 3, offering built-in haptic feedback and manipulation of the entire scope with one hand. Manipulation of the flexible endoscope is done entirely remotely. However, inclusion of haptic feedback places a huge burden on the system. Our purpose in this study was to determine whether haptic feedback is needed in remote manipulation of a flexible endoscope. Methods Five endoscopists performed total colonoscopy using a colonoscopy training model. A trial was conducted in which the endoscope was inserted up to the cecum five times with haptic feedback and five times without haptic feedback. Insertion time, maximum and mean haptic force, and incidence of sigmoid colon overstretching were compared between groups. Results Insertion time was significantly shorter with haptic feedback than without, and overstretching of the sigmoid colon was less frequent. Insertion could thus be performed without using excessive force. Conclusion Haptic feedback is useful for remote control manipulation of flexible endoscopes.

Computerized feedback during colonoscopy training leads to improved performance: a randomized trial

Simulation-based training in colonoscopy is increasingly replacing the traditional apprenticeship method to avoid patient-related risk. Mentoring during simulation is necessary to provide feedback and to motivate, but expert supervisors are a scarce resource. We aimed to determine whether computerized feedback in simulated colonoscopy would improve performance, optimize time spent practicing, and optimize the pattern of training. Forty-four participants were recruited and randomized to either a feedback group (FG) or a control group (CG). Participants were allowed 2 hours of self-practice during which they could practice as they saw fit on 2 different cases: 1 easy and 1 difficult. The CG practiced without feedback, but the participants in the FG were given a score of progression every time they reached the cecum. All participants were tested on a different case after end of training. The primary outcome was the progression score in the final case, and secondary outcomes were time spent practicing and the training pattern. Regression analysis adjusting for sex was done because of an uneven sex distribution between groups (P= .026) and significantly higher performance scores by men (37.6, standard deviation [SD] 25.9) compared with women (19.7, SD 18.7); P= .012. The FG outperformed the CG in the final case, FG scoring 14.4 points (95% confidence interval [CI], 1.2-27.6) more than the CG; P= .033, and they spent more time practicing, FG practicing 25.8 minutes (95% CI, 11.6-39.9) more than the CG; P= .001. The FG practiced more on the easy case and reached the cecum 3.2 times more (95% CI, 2-4.5) during practice (P< .001). Our findings of this study revealed that an automatic, computerized score of progression duringsimulated colonoscopy motivates the novices to improve performance, optimizes time spent practicing, and optimizes their pattern of training. (Clinical trial registration number: NCT03248453.).

Quality indicators in pediatric colonoscopy in a low-volume center: Implications for training

AIMTo study implications of measuring quality indicators on training and trainees’ performance in pediatric colonoscopy in a low-volume training center.METHODSWe reviewed retrospectively the performance of pediatric colonoscopies in a training center in Malaysia over 5 years (January 2010-December 2015), benchmarked against five quality indicators: appropriateness of indications, bowel preparations, cecum and ileal examination rates, and complications. The European Society of Gastrointestinal Endoscopy guideline for pediatric endoscopy and North American Society for Pediatric Gastroenterology, Hepatology and Nutrition training guidelines were used as benchmarks.RESULTSMedian (± SD) age of 121 children [males = 74 (61.2%)] who had 177 colonoscopies was 7.0 (± 4.6) years. On average, 30 colonoscopies were performed each year (range: 19-58). Except for investigations of abdominal pain (21/177, 17%), indications for colonoscopies were appropriate in the remaining 83%. Bowel preparation was good in 87%. One patient (0.6%) with severe Crohn’s disease had bowel perforation. Cecum examination and ileal intubation rate was 95% and 68.1%. Ileal intubation rate was significantly higher in diagnosing or assessing inflammatory bowel disease (IBD) than non-IBD (72.9% vs 50.0% P = 0.016). Performance of four trainees was consistent throughout the study period. Average cecum and ileal examination rate among trainees were 97% and 77%.CONCLUSIONBenchmarking against established guidelines helps units with a low-volume of colonoscopies to identify area for further improvement.

Colonoscopy education for surgical residents in Korea: a national survey of Korean Surgical Skill Study Group.

PurposeA standardized colonoscopy training program surgical residents is still unestablished. The aim of this study was to assess the current status of colonoscopy training for surgical residents and collect the opinions on the direction for future colonoscopy education.MethodsA questionnaire survey containing 24 items was conducted by sending an email to 310 colorectal surgeons in 84 training hospitals across the country.ResultsOne hundred fifteen staff surgeons (115 of 310, 37%) of 84 institutions returned fully completed questionnaires. Most surgeons were working at tertiary hospitals with more than 5 years of clinical experience. About half of the responding surgeons answered that they perform colonoscopy in clinical practice and the main purpose of colonoscopy was follow-up after colorectal resection. Only 9 of 84 hospitals (10.7%) had a regular program on colonoscopy training for surgical residents. Most of colonoscopy education was conducted irregularly in a form of staff lecture, conferences or hands-on workshops. According to the future directions, 72 of 115 surgeons (62.6%) answered judging competency in colonoscopy should be needed for professional qualification of the surgeon. About 50 cases of colonoscopy seem appropriate during the 4-year-training of surgical residency, especially during the third- and fourth-year.ConclusionThis survey shows colonoscopy education for surgical residents is still insufficient in Korea and that most surgeons feel that regular colonoscopy training is needed during the surgical residency period. There needs to be efforts to standardize the education program as well as various institutional and academic societal supports to achieve this goal.

Colonoscopy learning curves for colorectal surgery fellow trainees: experiences with the 15-year colonoscopy training program.

PurposeThis study aimed to analyze the learning curves for colorectal surgery fellows in a colonoscopy training program.MethodsBetween May 2003 and February 2017, 60 surgical fellows joined our 1-year colonoscopy training program as trainees and performed 43,784 cases of colonoscopy. All trainees recorded their colonoscopy experiences prospectively into the database. After excluding 6 trainees, who had experience with performing more than 50 colonoscopies before participating in our training program or who discontinued our training program with experience performing less than 300 colonoscopies, this study included 54 trainees who had performed 39,539 colonoscopy cases. We analyzed the cecal intubation rate (CIR) and cecal intubation time (CIT) using the cumulative sum (Cusum) technique and moving average method to assess the technical colonoscopy competence.ResultsOverall, the CIR by the trainees was 80.7%. The median number of cases of colonoscopy performed during the training period for each trainee was 696 (range, 322–1,669). The trainees were able to achieve a 90% CIR with 412 and 493 procedures when analyzed using the moving average and the Cusum, respectively. Using the moving average method, CIRs after 150, 300, and 400 procedures were 67.0%, 84.1%, and 89.2%, respectively. The CIT of trainees continuously decreased until 400 successful cases. Median CITs were 9.4, 8.3, and 7.4 minutes at 150, 300, and 400 successful cases, respectively.ConclusionWe found that more than 400 cases of experience were needed for technical competence in colonoscopy. Continuous teaching and monitoring is required until trainees become sufficiently competent.

Objective assessment of colonoscope manipulation skills in colonoscopy training.

Manipulation of the colonoscope is a technical challenge for novice clinicians which is best learned in a simulated environment. It involves the coordination of scope tip steering with scope insertion, using a rotated image as reference. The purpose of this work is to develop and validate a system which objectively assesses colonoscopy technical skills proficiency in an arbitrary training environment, allowing novices to assess their technical proficiency prior to real patient encounters. We implemented a motion tracking setup to objectively analyze and assess the way operators perform colonoscopies, including an analysis of wrist and elbow joint motions. Subsequently, we conducted a validation study to verify whether our motion analysis could discriminate novice colonoscopists from experts. Participants navigated a wooden bench-top model using a standard colonoscope while their motions were tracked. The developed motion tracking setup allowed colonoscopists of varying levels of proficiency to have their colonoscope manipulation assessed, and was able to be operated by a trained non-technical operator. Novice operators had significantly greater median times (101.5 vs. 31.5s) and number of hand movements (62.0 vs. 21.5) than experts. Experts, however, spent a significantly greater proportion of time in extreme ranges of wrist and elbow joint motion than novices. We have developed and implemented a hand and joint motion analysis system that is able to discriminate novices from experts based on objective measures of motion. These metrics could, thus, serve as proxies for technical proficiency during training.

The first homemade colonoscopy trainer.

Introduction Colonoscopy trainers have gained recognition for improving endoscopy skills and preparing for real procedures on humans. Unfortunately, due to their high price, commercial simulators are hard to obtain, especially for small medical centers. However, a solution might be to construct a device for themselves. Aim Our goal was to build a relatively cheap and easy-to-construct simulator for residents who want to start learning colonoscopy. Materials and methods The box model colonoscopy trainer was designed and constructed. The artificial colon was made from 2 layers of fabric and rubber rings between them. Velcro attached to the artificial colon and to the box, and the tarp straps that simulate peritoneal adhesions allow the bowel to be arranged in many different configurations. Moreover, some aspects of polypectomy training have been incorporated in the colonoscopy simulator. Results The self-constructed simulator was found to be an effective training device, with the total cost of parts not exceeding $30. Conclusions In this paper, we present the first homemade simulator for colonoscopy training. It offers the opportunity for skills acquisition in a preclinical setting.

Training in Endoscopy: Colonoscopy.

Colonoscopy is effective in reducing the morbidity and mortality associated with colorectal cancer (CRC). Interval cancers or post-colonoscopy CRCs, are cancers detected within the surveillance interval, or between 6–36 months after a clearing colonoscopy. The incidence of interval cancers is 3.4%–9.2% of all detected CRCs, as reported in population-based studies. Colonoscopy is a technically difficult procedure that is challenging to learn, and needs time and effort to gain competency. Therefore, trainee competence is a critical component of CRC screening and surveillance. Herein, we review the colonoscopy training methods and quality assessment metrics for colonoscopy competency.

Quality Indicators in Colonoscopy.

Colonoscopy is one of the most commonly performed endoscopic procedures. It is the gold standard examination for work-up of colonic symptoms, for follow-up of positive colorectal cancer screening tests and for detection and removal of neoplastic polyps. Colonoscopy is a complex and invasive procedure with a potential not only for colorectal cancer prevention, but also for serious complications. Numerous factors may affect the balance of benefit versus harm of colonoscopy, including the performance of the endoscopist. These factors are commonly called quality indicators. As an increasing number of countries are recommending the general population to undergo colorectal cancer screening, the quality of colonoscopy should be considered a public health concern. Key quality indicators have been identified, and several professional organizations have issued recommendation statements to promote high-quality colonoscopy. To achieve high quality, these key quality indicators must be monitored, results must be analysed, and measures must be undertaken to correct substandard performance. High-quality training in colonoscopy and polypectomy should be a quality assurance priority.

Lower Gastrointestinal Endoscopy

Since the advent of the first flexible fiberoptic sigmoidoscope in 1967, lower gastrointestinal endoscopy equipment has technologically advanced and is used for a number of diagnostic and therapeutic procedures. This review covers the definition of and indications for lower endoscopy; diagnostic and screening colonoscopy, bowel preparation for colonoscopy, special considerations for patients on anticoagulants and antiplatelet agents; endocarditis prophylaxis; general technique; diagnostic and therapeutic techniques during colonoscopy, sigmoidoscopy, anoscopy, endoscopic ultrasonography, balloon-assisted colonoscopy, and lower endoscopy training; and innovations on the horizon. Figures show room setup and patient positioning for colonoscopy; technique for insertion of a colonoscope and endoluminal view of rectum, descending colon, transverse colon, and cecum; pinch biopsy and hot biopsy forceps; snare polypectomy and endomucosal resection of a polyp using the lift and cut and suction cap techniques; Haggitt classification of tissue invasion in a pedunculated polyp; endoscopic clips and their application; self-expanding uncovered metal stents and their method of deployment; an anoscope; and rigid endorectal probes for endoscopic ultrasonography. Tables list indications for colonoscopy, recommendations for screening for colorectal cancer (average risk) from the US Preventive Services Task Force, recommendations from the US Multi-Society Task Force for surveillance after baseline colonoscopy in average-risk individuals, recommendations from the US Multi-Society Task Force for screening and surveillance in colorectal cancer (high risk), bowel preparation scales, agents for bowel preparation prior to colonoscopy, and Haggitt classification of tumor invasiveness in an adenomatous polyp. This review contains 10 highly rendered figures, 7 tables, and 60 references.

A novel physical colonoscopy simulator based on analysis of data from computed tomography colonography

PurposeLaparoscopic surgery is now practiced widely because of its lower postoperative morbidity. As flexible endoscopy during laparoscopic surgery minimizes surgical trauma further, training in endoscopy will become more important for surgeons. Thus, we designed a physical simulator, the Noda–Kitada–Suzuki (NKS) model, which could provide the more realistic insertion of a colonoscope.MethodsWe designed a colonoscopy simulator, based on information from computed tomography colonography scans of the anatomy and kinetic properties of the colon and rectum.ResultsThe transparent skeleton body of the NKS model provides instant visual feedback to the operator and the trainer. Our novel colonoscopy simulator replicates the realistic and reproducible insertion of a colonoscope from the rectum to cecum, providing authentic views of the Houston’s valves, the flexures, and mucosal folds. This was verified through an objective questionnaire, with 14 of 16 colonoscopists preferring the NKS model over the previous CM15 model for training purposes. Moreover, the Modified Colonoscopy Simulator Realism Questionnaire analysis confirmed that the NKS model was significantly more realistic than the CM15 for 7 (21.2%) of the 33 items when assessed by 12 colonoscopists.ConclusionThe NKS model provides a realistic training platform and may improve the quality of training in colonoscopy.

Air Insufflation vs Water Exchange Colonoscopy: A Multiple Cross-over, N-of-1 Study in a Trainee

Introduction: Water exchange (WE) colonoscopy is associated with less discomfort when compared to air insufflation (AI); other likely advantages include a lesser occurrence of loop formation and a higher adenoma detection rate. Yet despite these advantages, colonoscopy training in most endoscopy programs starts with AI. Aim: To study outcomes in a trainee who was randomly assigned to AI vs. WE during the first two weeks of colonoscopy training. Methods: For AI the trainee followed the advice of various staff members; there was no protocol. For WE the trainee worked with a single endoscopist who instructed the following method: (1) all air was removed during insertion and water was used to identify proximal colon; (2) stool containing water was exchanged for clean water; (3) water volume was maintained at the lowest amount allowing endoscope advancement; (4) mandatory rotation of the patient from left to back at the splenic flexure; (5) manual pressure with splenic and hepatic flexure passage. Data collected included gender, age, sedation, insertion extent and time, total time, loop formation, number and type of polyps; T-test was used for analysis. Results: The trainee performed 35 procedures in the first 2 weeks of training with multiple cross-overs: 3AI - 3WE - 4AI - 4WE - 3AI - 4WE - 10AI - 4WE. Gender distribution was 4/20 for AI and 4/15 for WE; ages were 65±9 year (M±SD ) for AI and 60±7 for WE (p=0.15). For AI cecal intubation was successful in 12/20 (60%) patients during 21±9min; for WE this was 14/15 (93%) during 9±3min (p < 0.001). The terminal ileum was intubated in 1/20 during AI and 10/15 during WE. Significant loop formation occurred in 7/20 during AI and 1/15 during WE. For AI sedation consisted of fentanyl 96±32mcg and midazolam 4.5±1.8mg; for WE this was 57±20mcg and 2.5±0.6mg (p < 0.001 both). The ADR was 0.5 during AI and 0.66 during WE (p=.33). Total endoscopy time was 47±18min for AI vs. 42±6min for WE (p=.44). Limitations: This is the experience of a single trainee. The WE technique was more structured than the AI technique. During later AI colonoscopies the trainee started using WE techniques given the experience with WE. Conclusion: WE is statistically superior to AI for most features that were measured for this starting trainee: insertion time, cecal and terminal ileum intubation rates, prevention of loop formation and need for sedation. WE had a trend towards a higher ADR and shorter total endoscopy time. WE should be considered as starting technique for colonoscopy training.