Variation in colonoscopic technique and adenoma detection rates at an academic gastroenterology unit

Association Between Longer Cecal Intubation Time and Detection and Miss Rate of Colorectal Neoplasms

Background/Aims: A longer cecal intubation time (CIT) occurs during colonoscopy under difficult insertion conditions, which may hinder meticulous mucosal observation. However, whether a longer CIT has detrimental effects on the detection of adenomas remains unclear. We evaluated the effects of CIT on the detection and miss rates of colorectal neoplasms in asymptomatic participants. Methods: Healthy examinees who underwent colonoscopy between March and July 2011, August 2015, and December 2016 were retrospectively enrolled. The primary outcome was the adenoma detection rate (ADR) across CIT quartiles, while the secondary outcomes included the mean number of adenomas, advanced ADR (AADR), clinically significant serrated lesion (CSSP) detection, adenoma miss rate (AMR), miss rate of CSSPs and any colorectal neoplasms, and the mean number of missed colorectal neoplasms in relation to CIT. Results: Overall, 12,402 participants were classified into quartiles according to the CIT. The longer the CIT, the lower the ADR (p < 0.001), AADR (p = 0.004), and mean number of adenomas (p < 0.001). The CSSP detection rate was not associated with CIT. On follow-up colonoscopy, AMR showed marginal increase with longer CIT (p = 0.065). The missed rates of CSSPs (p = 0.002) and colorectal neoplasms (p = 0.001) also increased with longer CIT. In the multivariate analysis, CIT was significantly associated with ADR, AADR, and AMR. Conclusions: Longer CIT was associated with lower ADR and higher AMR. Meticulous inspection is important for high-quality colonoscopy, particularly in patients requiring a longer CIT.

Image acquisition as novel colonoscopic quality indicator: a single-center retrospective study

PURPOSE

In order to reduce the incidence and mortality of colorectal cancer, improving the quality of colonoscopy is the top priority. At present, the adenoma detection rate is the most used index to evaluate the quality of colonoscopy. So, we further verified the relevant factors influencing the quality of colonoscopy and found out the novel quality indicators by studying the relationship between the influencing factors and the adenoma detection rate.

MATERIALS/METHODS

The study included 3824 cases of colonoscopy from January to December 2020. We retrospectively recorded the age and sex of the subjects; the number, size, and histological features of lesions; withdrawal time and the number of images acquired during colonoscopy. We analyzed the associated factors affecting adenoma and polyp detection, and verified their effectiveness with both univariate and multivariate logistic regression analyses.

RESULTS

Logistic regression analyses showed that gender, age, withdrawal time and the number of images acquired during colonoscopy could serve as independent predictors of adenoma/polyp detection rate. In addition, adenoma detection rate (25.36% vs. 14.29%) and polyp detection rate (53.99% vs. 34.42%) showed a marked increase when the number of images taken during colonoscopy was ≥29 (P<0.001).

CONCLUSIONS

Gender, age, withdrawal time and the number of images acquired during colonoscopy are influencing factors for the detection of colorectal adenomas and polyps. And we can gain higher adenoma/polyp detection rate when endoscopists capture more colonoscopic images.

Complementary Effect of the Proportion of Overspeed Frames of Withdrawal and Withdrawal Time on Reflecting Colonoscopy Quality: A Retrospective, Observational Study

INTRODUCTION

Constructing quality indicators that reflect the defect of colonoscopy operation for quality audit and feedback is very important. Previously, we have established a real-time withdrawal speed monitoring system to control withdrawal speed below the safe speed. We aimed to explore the relationship between the proportion of overspeed frames (POF) of withdrawal and the adenoma detection rate (ADR) and to conjointly analyze the influence of POF and withdrawal time on ADR to evaluate the feasibility of POF combined with withdrawal time as a quality control indicator.

METHODS

The POF was defined as the proportion of frames with instantaneous speed ≥44 in the whole colonoscopy video. First, we developed a system for the POF of withdrawal based on a perceptual hashing algorithm. Next, we retrospectively collected 1,804 colonoscopy videos to explore the relationship between POF and ADR. According to withdrawal time and POF cutoff, we conducted a complementary analysis on the effects of POF and withdrawal time on ADR.

RESULTS

There was an inverse correlation between the POF and ADR (Pearson correlation coefficient -0.836). When withdrawal time was >6 minutes, the ADR of the POF ≤10% was significantly higher than that of POF >10% (25.30% vs 16.50%; odds ratio 0.463, 95% confidence interval 0.296-0.724, P < 0.01). When the POF was ≤10%, the ADR of withdrawal time >6 minutes was higher than that of withdrawal time ≤6 minutes (25.30% vs 21.14%; odds ratio 0.877, 95% confidence interval 0.667-1.153, P = 0.35).

DISCUSSION

The POF was strongly correlated with ADR. The combined assessment of the POF and withdrawal time has profound significance for colonoscopy quality control.

Longer withdrawal time is not associated with increased patient discomfort in colonoscopy: a retrospective observational study

PURPOSE

Withdrawal time of sufficient length is a quality indicator for colonoscopies. Nonetheless, whether extending the withdrawal time contributes to patient discomfort remains unknown. This study aimed to clarify the relationship between colonoscopy withdrawal time and patient discomfort.

METHODS

A cohort of consecutive patients who underwent colonoscopy at a single institution from October 2018 to January 2020 was retrospectively analyzed. Initially, the relationship between the mean withdrawal time for each colonoscopist in no-finding examinations and polyp detection rate was investigated in 2,043 patients. Subsequently, the primary outcome of association between withdrawal time and patient discomfort, as determined by patient questionnaire, was assessed for each examination in 481 patients from the initial cohort.

RESULTS

The mean withdrawal time was strongly correlated with polyp detection rate (correlation coefficient, 0.72; P<0.001). In contrast, longer withdrawal time was not associated with increased discomfort; however, there was a weak inverse correlation between patient discomfort and longer withdrawal time (correlation coefficient, -0.25; P<0.001). Similarly, multiple regression analysis adjusted for confounding variables revealed that longer withdrawal time was not associated with increased patient discomfort (regression coefficient, -0.04 for each 1-minute increase in the length of withdrawal time; P=0.45).

CONCLUSION

This study showed for the first time that longer withdrawal times did not result in increased discomfort, indicating that withdrawal time can be extended to sufficient length for optimal patient examination and polyp detection.

Negative effect of prolonged cecal intubation time on adenoma detection in female patients

Background and Aim

Withdrawal time of the colonoscope is associated with adenoma detection. However, the association between cecal intubation time and adenoma detection remains unclear. This study aimed to evaluate the association between cecal intubation time and adenoma detection.

Methods

This retrospective study analyzed prospectively collected data from a randomized controlled trial on female patients who underwent colonoscopy in an academic hospital. The primary outcome was the mean number of all adenomas detected per patient. Secondary outcomes included the mean number of advanced, diminutive, small/large, right-sided colonic, and left-sided colonic adenomas detected per patient. Furthermore, the detection rates of all categories of adenoma were evaluated.

Results

The analysis included 216 female patients aged ≥20 years. The correlation analysis did not reveal a significant relationship (P = 0.473) between cecal intubation and withdrawal times. The mean number of all adenomas detected per patient declined by approximately 30% (1.05-0.70) from the fastest to the slowest insertion time quartile. Adjusted regression analysis showed a significant decrease in the mean number of all adenomas detected per patient with increased intubation time (relative risk, RR = 0.87; 95% confidence interval, 0.76-0.99, P = 0.045), whereas the mean number of other categories of adenomas detected per patient and the detection rates of all categories of adenoma were not associated with the cecal intubation time.

Conclusions

This study showed a significant association between prolonged cecal intubation time and decreased adenoma detection. The cecal intubation time may be a significant quality indicator for colonoscopy.

A video based benchmark data set (ENDOTEST) to evaluate computer-aided polyp detection systems

BACKGROUND AND AIMS

Computer-aided polyp detection (CADe) may become a standard for polyp detection during colonoscopy. Several systems are already commercially available. We report on a video-based benchmark technique for the first preclinical assessment of such systems before comparative randomized trials are to be undertaken. Additionally, we compare a commercially available CADe system with our newly developed one.

METHODS

ENDOTEST consisted in the combination of two datasets. The validation dataset contained 48 video-snippets with 22,856 manually annotated images of which 53.2% contained polyps. The performance dataset contained 10 full-length screening colonoscopies with 230,898 manually annotated images of which 15.8% contained a polyp. Assessment parameters were accuracy for polyp detection and time delay to first polyp detection after polyp appearance (FDT). Two CADe systems were assessed: a commercial CADe system (GI-Genius, Medtronic), and a self-developed new system (ENDOMIND). The latter being a convolutional neuronal network trained on 194,983 manually labeled images extracted from colonoscopy videos recorded in mainly six different gastroenterologic practices.

RESULTS

On the ENDOTEST, both CADe systems detected all polyps in at least one image. The per-frame sensitivity and specificity in full colonoscopies was 48.1% and 93.7%, respectively for GI-Genius; and 54% and 92.7%, respectively for ENDOMIND. Median FDT of ENDOMIND with 217 ms (Inter-Quartile Range(IQR)8-1533) was significantly faster than GI-Genius with 1050 ms (IQR 358-2767, p = 0.003).

CONCLUSIONS

Our benchmark ENDOTEST may be helpful for preclinical testing of new CADe devices. There seems to be a correlation between a shorter FDT with a higher sensitivity and a lower specificity for polyp detection.

Detection rates of colorectal neoplasia during colonoscopies and their associated factors in the SCREESCO study

BACKGROUND AND AIM

Colonoscopy quality, including lesion detectability, is variable, and factors influencing lesion detection are not fully understood. This study investigated lesion detection rates during colonoscopies and the associated factors in the SCREEning of Swedish COlons (SCREESCO) study.

METHODS

In this cross-sectional analysis of data from SCREESCO, a large-scale randomized controlled trial of colorectal cancer screening in the Swedish population aged 60 years, we assessed data of first-time colonoscopies performed in both colonoscopy and fecal immunochemical test (FIT) arms.

RESULTS

This study included 16 552 individuals. The adenoma detection rate was 23.9% and 37.8% in colonoscopy and FIT arms, respectively. Regarding colonoscopy procedures, a withdrawal time ≥ 6 min was associated with higher detection rates of advanced adenomas (adjusted odds ratio [AOR] 2.474, 95% confidence interval [CI] 1.295-4.723), adenomas (2.181, 1.515-3.140), and proximal serrated lesions (pSLs) (1.713, 1.007-2.915). Antispasmodic use was associated with higher detection rates of these lesions and sessile serrated lesions (SSLs) (AOR, 95% CI: 1.523, 1.295-1.791; 1.361, 1.217-1.522; 1.450, 1.247-1.687; and 1.810, 1.512-2.167, respectively). Insertion time > 20 min was related to lower detection rates of adenomas, pSLs, and SSLs (AOR, 95% CI: 0.753, 0.639-0.887; 0.640, 0.495-0.828; and 0.704, 0.518-0.955, respectively). The relationship between a recent period and higher detection rates of pSLs and SSLs was also demonstrated.

CONCLUSION

Lesion detectability in SCREESCO was mostly acceptable with room for improvement. In addition to sufficient withdrawal time, antispasmodic use and acquiring skills enabling short insertion time may improve lesion detection.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02078804.

A Gastrointestinal Endoscopy Quality Control System Incorporated With Deep Learning Improved Endoscopist Performance in a Pretest and Post-Test Trial

INTRODUCTION

Gastrointestinal endoscopic quality is operator-dependent. To ensure the endoscopy quality, we constructed an endoscopic audit and feedback system named Endo.Adm and evaluated its effect in a form of pretest and posttest trial.

METHODS

Endo.Adm system was developed using Python and Deep Convolutional Neural Ne2rk models. Sixteen endoscopists were recruited from Renmin Hospital of Wuhan University and were randomly assigned to undergo feedback of Endo.Adm or not (8 for the feedback group and 8 for the control group). The feedback group received weekly quality report cards which were automatically generated by Endo.Adm. We then compared the adenoma detection rate (ADR) and gastric precancerous conditions detection rate between baseline and postintervention phase for endoscopists in each group to evaluate the impact of Endo.Adm feedback. In total, 1,191 colonoscopies and 3,515 gastroscopies were included for analysis.

RESULTS

ADR was increased after Endo.Adm feedback (10.8%-20.3%, P < 0.01,

DISCUSSION

Endo.Adm feedback contributed to multifaceted gastrointestinal endoscopic quality improvement. This system is practical to implement and may serve as a standard model for quality improvement in routine work (http://www.chictr.org.cn/, ChiCTR1900024153).

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MESH Headings

• Adenoma/diagnostic imaging
• Adenoma/epidemiology
• Adult
• China
• Clinical Competence
• Colonoscopy/standards
• Deep Learning
• Early Detection of Cancer
• Feedback
• Female
• Humans
• Male
• Middle Aged
• Quality Improvement
• Quality Indicators, Health Care/statistics & numerical data
• Risk Factors

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Affiliation(s)

Liwen Yao Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Jun Liu Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Lianlian Wu Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Lihui Zhang Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Xiao Hu Wuhan ENDOANGEL Medical Technology Company, Wuhan, China;
Jinzhu Liu Wuhan ENDOANGEL Medical Technology Company, Wuhan, China;
Zihua Lu Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Dexin Gong Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Ping An Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Jun Zhang Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Guiying Hu Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Di Chen Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Renquan Luo Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;
Shan Hu Wuhan ENDOANGEL Medical Technology Company, Wuhan, China;
Yanning Yang Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, China.
Honggang Yu Department of Gastroenterology, Renmin Hospital of Wuhan University, Wuhan, China; Key Laboratory of Hubei Province for Digestive System Disease, Renmin Hospital of Wuhan University, Wuhan, China; Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Renmin Hospital of Wuhan University, Wuhan, China;

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Trainee participation during screening colonoscopy does not affect ADR at subsequent surveillance, but may result in early follow-up

Background and study aims  Training future endoscopists is essential to meet rising demands for screening and surveillance colonoscopies. Studies have shown conflicting results regarding the influence of trainees on adenoma detection rates (ADR). It is unclear whether trainee participation during screening adversely affects ADR at subsequent surveillance and whether it alters surveillance recommendations. Patients and methods  A retrospective analysis of average-risk screening colonoscopies and surveillance exams over a subsequent 10-year period was performed. The initial inclusion criteria were met by 5208 screening and 2285 surveillance exams. Patients with poor preparation were excluded. The final analysis included 7106 procedures, including 4922 screening colonoscopies and 2184 surveillance exams. Data were collected from pathology and endoscopy electronic databases. The primary outcome was the ADR with and without trainee participation. Surveillance recommendations were analyzed as a secondary outcome. Results  Trainees participated in 1131 (23 %) screening and in 232 (11 %) surveillance exams. ADR did not significantly differ ( P  = 0.19) for screening exams with trainee participation (19.5 %) or those without (21.4 %). ADRs were higher at surveillance exams with (22.4 %) and without (27.5 %) trainee participation. ADR at surveillance was not adversely affected by trainee participation during the previous colonoscopy. Shorter surveillance intervals were given more frequently if trainees participated during the initial screening procedure ( P  = 0.0001). Conclusions  ADR did not significantly differ in screening or surveillance colonoscopies with or without trainee participation. ADR at surveillance was not adversely affected by trainee participation during the previous screening exam. However, trainee participation may result in shorter surveillance recommendations.

Detection of colorectal adenomas with a real-time computer-aided system (ENDOANGEL): a randomised controlled study

BACKGROUND

Colonoscopy performance varies among endoscopists, impairing the discovery of colorectal cancers and precursor lesions. We aimed to construct a real-time quality improvement system (ENDOANGEL) to monitor real-time withdrawal speed and colonoscopy withdrawal time and to remind endoscopists of blind spots caused by endoscope slipping. We also aimed to evaluate the effectiveness of this system for improving adenoma yield of everyday colonoscopy.

METHODS

The ENDOANGEL system was developed using deep neural networks and perceptual hash algorithms. We recruited consecutive patients aged 18-75 years from Renmin Hospital of Wuhan University in China who provided written informed consent. We randomly assigned patients (1:1) using computer-generated random numbers and block randomisation (block size of four) to either colonoscopy with the ENDOANGEL system or unassisted colonoscopy (control). Endoscopists were not masked to the random assignment but analysts and patients were unaware of random assignments. The primary endpoint was the adenoma detection rate (ADR), which is the proportion of patients having one or more adenomas detected at colonoscopy. The primary analysis was done per protocol (ie, in all patients having colonoscopy done in accordance with the assigned intervention) and by intention to treat (ie, in all randomised patients). This trial is registered with http://www.chictr.org.cn, ChiCTR1900021984.

FINDINGS

Between June 18, 2019, and Sept 6, 2019, 704 patients were randomly allocated colonoscopy with the ENDOANGEL system (n=355) or unassisted (control) colonoscopy (n=349). In the intention-to-treat population, ADR was significantly greater in the ENDOANGEL group than in the control group, with 58 (16%) of 355 patients allocated ENDOANGEL-assisted colonoscopy having one or more adenomas detected, compared with 27 (8%) of 349 allocated control colonoscopy (odds ratio [OR] 2·30, 95% CI 1·40-3·77; p=0·0010). In the per-protocol analysis, findings were similar, with 54 (17%) of 324 patients assigned ENDOANGEL-assisted colonoscopy and 26 (8%) of 318 patients assigned control colonoscopy having one or more adenomas detected (OR 2·18, 95% CI 1·31-3·62; p=0·0026). No adverse events were reported.

INTERPRETATION

The ENDOANGEL system significantly improved the adenoma yield during colonoscopy and seems to be effective and safe for use during routine colonoscopy.

FUNDING

Hubei Provincial Clinical Research Center for Digestive Disease Minimally Invasive Incision, Hubei Province Major Science and Technology Innovation Project, and the National Natural Science Foundation of China.

Identification of cecum time-location in a colonoscopy video by deep learning analysis of colonoscope movement

Background

Cecal intubation time is an important component for quality colonoscopy. Cecum is the turning point that determines the insertion and withdrawal phase of the colonoscope. For this reason, obtaining information related with location of the cecum in the endoscopic procedure is very useful. Also, it is necessary to detect the direction of colonoscope's movement and time-location of the cecum.

Methods

In order to analysis the direction of scope's movement, the Horn-Schunck algorithm was used to compute the pixel's motion change between consecutive frames. Horn-Schunk-algorithm applied images were trained and tested through convolutional neural network deep learning methods, and classified to the insertion, withdrawal and stop movements. Based on the scope's movement, the graph was drawn with a value of +1 for insertion, -1 for withdrawal, and 0 for stop. We regarded the turning point as a cecum candidate point when the total graph area sum in a certain section recorded the lowest.

Results

A total of 328,927 frame images were obtained from 112 patients. The overall accuracy, drawn from 5-fold cross-validation, was 95.6%. When the value of "t" was 30 s, accuracy of cecum discovery was 96.7%. In order to increase visibility, the movement of the scope was added to summary report of colonoscopy video. Insertion, withdrawal, and stop movements were mapped to each color and expressed with various scale. As the scale increased, the distinction between the insertion phase and the withdrawal phase became clearer.

Conclusion

Information obtained in this study can be utilized as metadata for proficiency assessment. Since insertion and withdrawal are technically different movements, data of scope's movement and phase can be quantified and utilized to express pattern unique to the colonoscopist and to assess proficiency. Also, we hope that the findings of this study can contribute to the informatics field of medical records so that medical charts can be transmitted graphically and effectively in the field of colonoscopy.

Prolonged Cecal Insertion Time Is Not Associated with Decreased Adenoma Detection When a Longer Withdrawal Time Is Achieved

BACKGROUND

The association between withdrawal time and adenoma detection has been established; however, the effect of cecal insertion time on adenoma detection remains unclear.

AIM

To determine the association between cecal insertion time and adenoma detection.

METHODS

This study completed a retrospective analysis of data collected in 4 prospective randomized-controlled trials related to screening and surveillance colonoscopy at a single tertiary care from 2010 to 2016. The primary outcome was cecal insertion time and its association with mean number of adenomas per patient and adenoma detection rate (ADR).

RESULTS

1303 patients met inclusion criteria (average age 59.7 ± 8.7 years; 759 females (58.3%), and 763 Caucasians (58.6%). Mean cecal insertion time was significantly longer in patients who were female (p < 0.001), received moderate sedation (p = 0.001), had fellow involvement (p < 0.001), older (p = 0.002), and lower Boston bowel preparation scale (p < 0.001). Withdrawal time was found to increase as mean cecal insertion time increased (p < 0.001). The mean cecal insertion time was not different in patients with or without adenomas (p = 0.94). Cecal insertion time did not correlate with the mean number of adenomas or advanced adenomas per patient (p > 0.05), which was also true on Poisson regression analysis. Adenomas and advanced adenomas per patient were found to decrease when cecal insertion to withdrawal time ratios were greater than 1 (p < 0.001).

CONCLUSIONS

Prolonged cecal insertion time was not associated with a decrease in ADR, mean number of adenomas or advanced adenomas per patient. When withdrawal times were longer than cecal insertion times, the number of adenomas and advanced adenomas detected per patient was significantly improved.

Colonoscopic withdrawal time and adenoma detection in the right colon

Shorter colonoscopic withdrawal time (CWT) has been associated with lower adenoma detection rate (ADR), which can increase the risk of interval colorectal cancer (ICC) that commonly arises in the right colon (RC). Therefore, a better ADR in the RC could decrease the incidence of ICC. We analyzed the relationship between CWT and ADR in the RC and entire colon.We retrospectively reviewed the patients who had undergone screening colonoscopy at Chungnam National University Hospital between March 2015 and February 2016. We enrolled 5370 patients in whom colonoscopies were performed by 7 gastroenterologists. We categorized patients into 4 groups in the RC and 6 groups in the entire colon by CWT. Multivariable analysis was used for detection of adenoma in the RC and entire colon.In the RC, the odds ratio (OR) of CWT longer than 3 minutes was 3.70, compared to CWT of <2 minutes [3.06-4.85, 95% confidence interval (CI), P < .001]. In the entire colon, the OR of CWT between 9 to 10 minutes and longer than 10 minutes was 3.34 [2.61-4.27, 95% CI, P < .001] and 3.49 [2.80-4.33, 95% CI, P < .001] compared to CWT of <6 minutes.Based on our result, we suggest that the optimum CWT in the RC should exceed 3 minutes, and considering the "ceiling effect," the optimum CWT in the entire colon should exceed 9 minutes.

Multitarget stool DNA test: clinical performance and impact on yield and quality of colonoscopy for colorectal cancer screening

BACKGROUND AND AIMS

Multitarget stool DNA (MT-sDNA) testing is now approved by the U.S. Food and Drug Administration for average-risk colorectal cancer screening. Trials leading to its approval used blinded colonoscopy as the reference standard. In the postapproval screen setting, the clinical performance and impact of MT-sDNA testing on unblinded colonoscopy has not been described. We measured the impact that knowledge of a positive MT-sDNA test result has on colonoscopy yield and quality.

METHODS

The unblinded group comprised all patients with positive MT-sDNA results on screening from September 1, 2014 to September 30, 2015 at a single tertiary center. Off-label test patients were excluded. The blinded group included all MT-sDNA-positive participants in a preapproval screening study from the same center. Detailed colonoscopy findings and withdrawal times were recorded.

RESULTS

There were 172 MT-sDNA-positive patients in the unblinded group and 72 in the blinded group. More total adenomatous/sessile serrated polyps (70% vs 53%, P = .013) and advanced neoplasms (28% vs 21%, P = .27) were detected in unblinded than in blinded groups. Median numbers of polyps detected were 2 (IQR, 1-4) and 1 (IQR, 0-2) in unblinded and blinded groups, respectively (P = .0007). Among polyps detected, flat or slightly raised lesions in the right side of the colon were proportionately more frequent with unblinded (40%) than with blinded examinations (9%) (P = .0017). Median withdrawal time was 19 minutes (IQR, 13-29) in the unblinded group compared with 13 minutes (IQR, 10-20) in the blinded group (P = .0001).

CONCLUSIONS

Knowledge of a positive MT-sDNA result appears to have a beneficial impact on the diagnostic yield and quality of subsequent colonoscopy.

Prolonged cecal insertion time is associated with decreased adenoma detection

BACKGROUND AND AIMS

The adenoma detection rate (ADR) is an important colonoscopy quality parameter. A longer withdrawal time is associated with increased adenoma detection; however, the effect of cecal insertion time on adenoma detection is unclear. The aim of this study was to evaluate if cecal insertion time is associated with adenoma detection.

METHODS

The study included 50- to 89-year-old subjects undergoing an elective outpatient colonoscopy as part of a randomized trial on cap-assisted colonoscopy. The primary outcome was the adjusted mean number of adenomas per patient across quartiles of lengthening patient insertion times. Secondary outcomes included the mean number of advanced adenomas, ADR, and advanced ADR. Adjusted regression analysis was applied to assess for a possible trend.

RESULTS

Among 1043 included study subjects, the median cecal insertion time was 5.3 minutes (interquartile range [IQR], 3.5-8.1) and the median withdrawal time was 8.6 minutes (IQR, 7.1-10.7). Cecal insertion time was not associated with withdrawal time (P = .950). The mean number of adenomas per patient decreased across increasing insertion time quartiles from 1.1 to .7, corresponding to a 11% decline per quartile (P = .031). Similarly, the number of advanced adenomas decreased from .15 to .06, corresponding to a 7% decline per quartile (P = .013). The observed decrease in adenoma detection was similar for proximal and distal adenomas. Endoscopists' individual insertion times were not associated with adenoma detection.

CONCLUSIONS

A longer cecal insertion time was associated with a decreased detection of adenomas and advanced adenomas. A long insertion time may be a marker for a more difficult examination that requires a longer withdrawal time to assure adequate examination and adenoma detection. (Clinical trial registration number: NCT01935180.).

Colonoscopy practice for veterans within and outside the Veterans Affairs setting: a matched cohort study

BACKGROUND AND AIMS

To minimize delays for colonoscopy within Veterans Affairs (VA) facilities, veterans may receive care at non-VA facilities based on fee-for-service contracts, and more recently, through the Veterans Access, Choice, and Accountability Act. The impact of diverting care from VA to non-VA facilities on quality of colonoscopy practice is unknown.

METHODS

We identified all veterans aged 50 to 85 years who received a fee-basis colonoscopy for colorectal cancer screening or surveillance at non-VA facilities in 2007 to 2010. These patients were matched for sex, age, and year of procedure to veterans who underwent colonoscopies at VA medical centers. The outcomes of interest were the adenoma detection rates (ADR) and compliance with surveillance guidelines.

RESULTS

During the observation period, 409 veterans (mean age 64 years; 94% men) underwent a fee-basis colonoscopy at 30 nonacademic (54%) and 2 academic (46%) facilities. Compared with colonoscopies performed at VA facilities, fee-basis colonoscopy patients had lower ADRs (38% vs 52%; P < .001), lower mean number of adenomas per procedure (0.72 vs 1.41; P < .001), and lower number of advanced ADRs (13% vs 22%; P < .001). Colonoscopies done at non-VA facilities were associated with lower ADRs in multivariate regression analysis (odds ratio 0.64; 95% CI, 0.44-0.92), whereas colonoscopies done in nonacademic settings or by colonoscopists who were not gastroenterologists were not. Compliance with surveillance guidelines was lower for colonoscopies performed outside VA facilities (80% vs 87%; P = .03).

CONCLUSIONS

In this regional study (Northern New England), compliance with colonoscopy surveillance guidelines was high in both VA and non-VA settings; however, lower ADRs raise concern that referring veterans outside the VA system may impact colonoscopy quality.

Can Technology Improve the Quality of Colonoscopy?

In order for screening colonoscopy to be an effective tool in reducing colon cancer incidence, exams must be performed in a high-quality manner. Quality metrics have been presented by gastroenterology societies and now include higher adenoma detection rate targets than in the past. In many cases, the quality of colonoscopy can often be improved with simple low-cost interventions such as improved procedure technique, implementing split-dose bowel prep, and monitoring individuals' performances. Emerging technology has expanded our field of view and image quality during colonoscopy. We will critically review several technological advances in the context of quality metrics and discuss if technology can really improve the quality of colonoscopy.

Should Assessment of Quality Indicator of Colonoscopy Be Varied Depending on the Colonoscopic Technique Level?

BACKGROUND/AIM

The purpose of this research was to evaluate if withdrawal time is a useful index in spite of differences in gastroenterologists' ability and if there are other quality indicators of colonoscopy.

METHODS

A total of 665 consecutive, asymptomatic individuals of average risk between 50 and 75 years of age who underwent screening colonoscopies performed by 12 gastroenterologists were included in this study. The endoscopists were classified to either the experienced group (group A, N = 6) or the under-experienced group (group B, N = 6). The endoscopists were unaware that they were being studied during the two-month study period.

RESULTS

In group A, adenoma detection rate was 0.56, while in group B it was 0.43 (P = 0.048). The mean withdrawal time ranged widely from 4.2 to 10.3 min per patient with a mean value of 6.83 for group A and 6.54 for group B. There was a significantly positive relationship between the number of adenomas detected and the withdrawal time for group B (r = 0.827, P = 0.005), but not for group A (r = -0.152, P = 0.584). In the case of group A, the ratio of cecal intubation time to withdrawal time (I/E ratio) less than 1 showed significantly correlated adenoma detection rate compared to I/E ratio greater than 1 (r = -0.308, P = 0.036). In the case of group B, mean I/E ratio was 1.7 and all endoscopists' I/E ratios were greater than 1.

CONCLUSIONS

For experienced endoscopists, a useful supplementary quality indicator of colonoscopy is to keep intubation/withdrawal time ratio less than 1 and it is necessary for under-experienced endoscopists to try to keep enough withdrawal time.

Screening colonoscopy volume and detection of colorectal neoplasms: a state-wide study from Bavaria, Germany

Screening colonoscopy enables early detection of colorectal cancer and its precancerous lesions. The aim of this study was to assess the association of screening colonoscopy volume with colorectal neoplasm detection rate in routine practice. A registry-based study of individuals aged at least 55 years who underwent screening colonoscopy in Bavaria, Germany, between 2007 and 2009 was performed. Colorectal neoplasm detection rates (95% confidence intervals) were determined per physician. Physicians were grouped according to the number of screening colonoscopies performed per year (<50, 50-99, 100-199, ≥200). A total of 203 363 individuals (median age 64 years, 55.2% women) underwent screening colonoscopy between 2007 and 2009. Colonoscopies were performed by 509 physicians. The detection rate of any neoplasm increased with screening colonoscopy volume from 21.9% among physicians conducting fewer than 50 screening colonoscopies per year to 27.5% among physicians conducting 200 or more screening colonoscopies per year (P-value for trend <0.0001). Increases in detection rates with colonoscopy volume were also observed for advanced neoplasms and for colorectal cancer (P-value for trend 0.16 and <0.0001, respectively). Differences were largest between physicians conducting fewer than 50 screening colonoscopies per year and other physicians. These results support a potential role of a minimum colonoscopy volume for high-quality colonoscopy screening. Differences in neoplasm detection rates were high between physicians conducting fewer than 50 screening colonoscopies per year and physicians with higher screening colonoscopy volume.

Diagnostic yield of scope retroflexion in the right colon: A prospective cohort study

BACKGROUND

Techniques have been implemented to improve colonoscopy adenoma detection rate (ADR) in the right colon.

AIMS & METHODS

We prospectively examined the additional diagnostic yield of right colon examination with colonoscope retroflexion in consecutive, symptomatic and screening-surveillance patients. Right colon was examined in forward-view first and thereafter, retroflexion was performed to re-inspect it.

RESULTS

Right colon examination in retroflexion was achieved in 620 (92%) patients. Increased inserted scope length to the cecum (OR: 0.48 [95% CI: 0.27-0.84]) and elderly status (OR: 0.53 [95% CI: 0.430-0.94]) predicted retrofexion failure. Forward-view colonoscopy detected 134 polyps and 112 adenomas in 105 and 85 patients, respectively. Scope retroflexion revealed 7 missed (6 adenomas--2 advanced) polyps in 7 patients; indicating 4.96 (95% CI: 1.37-8.55) % and 5.1 (95% CI: 1.12-9.05) % per-polyp and per-adenoma miss rates, respectively. In ITT analysis, per-patient polyp and adenoma miss rates were 1.041% and 0.89%, respectively. Among screening-surveillance patients, retroflexion detected 3 missed adenomas (2 advanced) in 3 patients, resulting in changed surveillance schedule in 2 of them (5.12 per 1000 screening-surveillance patients). Early study termination was favored by low right colon ADR improvement and lacking substantial surveillance interval change.

CONCLUSION

The additional diagnostic yield of scope retroflexion in the right colon is questionable.

A novel quality scoring system for the evaluation of individual colonoscopy: A multicenter retrospective study

BACKGROUND AND AIM

It is essential to develop a novel evaluation system for the quality of individual colonoscopy and provide guidelines on whether and when to follow up the patient after the initial colonoscopy. This study aimed to establish and validate a scoring system for the quality of individual colonoscopy in terms of the adenoma miss rate (AMR).

METHODS

Patients undergoing two consecutive colonoscopies within 90 days between 2009 and 2011 from different levels of hospitals in China were enrolled into this study. Potential risk factors for adenoma miss at the individual colonoscopy in a cohort of patients were evaluated in univariate and multivariate analyses. Corresponding scores for the procedure-related factors were generated based on their weights, and a scoring system was established and then validated by correlating the system with AMR.

RESULTS

A total of 2093 patients were enrolled. Procedure-related factors at the individual colonoscopy (including bowel preparation and imaging methods), doctor experience, retroflexion, and withdrawal time were identified to be independent risk factors, and each of these factors was scored from 0 to 3. Then, a novel scoring system for the quality of individual colonoscopy (ranging from 0 to 9) was established, which was closely correlated with the AMRs in the establishment (adjusted R(2) = 0.845) and validation databases (adjusted R(2) = 0.733).

CONCLUSIONS

The developed and validated evaluation system, consisting of procedure-related independent factors, successfully assesses the quality of individual colonoscopy in terms of AMRs.

Improved bowel preparation increases polyp detection and unmasks significant polyp miss rate

AIM: To retrospectively compare previous-day vs split-dose preparation in terms of bowel cleanliness and polyp detection in patients referred for polypectomy.

METHODS: Fifty patients underwent two colonoscopies: one diagnostic in a private clinic and a second for polypectomy in a University Hospital. The latter procedures were performed within 12 wk of the index ones. Examinations were accomplished by two experienced endoscopists, different in each facility. Twenty-seven patients underwent screening/surveillance colonoscopy, while the rest were symptomatic. Previous day bowel preparation was utilized initially and split-dose for polypectomy. Colon cleansing was evaluated using the Aronchick scale. We measured the number of detected polyps, and the polyp miss rates per-polyp.

RESULTS: Excellent/good preparation was reported in 38 cases with previous-day preparation (76%) vs 46 with split-dose (92%), respectively (P = 0.03). One hundred and twenty-six polyps were detected initially and 169 subsequently (P < 0.0001); 88 vs 126 polyps were diminutive (P < 0.0001), 25 vs 29 small (P = 0.048) and 13 vs 14 equal or larger than 10 mm. The miss rates for total, diminutive, small and large polyps were 25.4%, 30.1%, 13.7% and 6.6%, respectively. Multivariate analysis revealed that split-dose preparation was significantly associated (OR, P) with increased number of polyps detected overall (0.869, P < 0.001), in the right (0.418, P = 0.008) and in the left colon (0.452, P = 0.02).

CONCLUSION: Split-dose preparation improved colon cleansing, enhanced polyp detection and unmasked significant polyp miss rates.

Effects of the no interruption zone on distraction levels, withdrawal times, and adenoma detection rates of colonoscopy

BACKGROUND

The creation of no interruption zones (NIZs) reduces medical errors by reducing distraction levels on hospital wards. To date, the effect of a NIZ during colonoscopy has not been evaluated.

AIMS

Assess the effects of a NIZ during colonoscopy, on distraction levels, withdrawal times, and adenoma detection rates (ADRs).

METHODS

This was a non-randomized prospective study of screening colonoscopies at a teaching hospital. The intervention, a NIZ, was created by limiting conversations to the care of the patient undergoing the procedure and posting a "do not disturb" sign during the withdrawal phase of colonoscopy. Distraction levels, withdrawal times, and ADRs were analyzed at baseline and after the NIZ.

RESULTS

The implementation of the NIZ leads to a significant reduction of high-distraction-level environments (13.1 vs. 5.1 %; p < 0.0001). There was a significant decrease in withdrawal time with NIZs; (10.6 vs. 9.9 min, p = 0.0038). There was no significant difference in ADRs (38 % baseline vs. 36 % NIZs, respectively; p = 0.33).

CONCLUSIONS

Creation of a NIZ was associated with a significant decrease in high-distraction environments and shorter withdrawal times with no significant change in ADRs. Further studies are needed to evaluate whether lower distraction levels in an endoscopy suite translate to improved quality measures.

Optimized sedation improves colonoscopy quality long-term

Background. Quality monitoring and improvement is prerequisite for efficient colonoscopy. Aim. To assess the effects of increased sedation administration on colonoscopy performance. Materials and Methods. During Era 1 we prospectively measured four colonoscopy quality indicators: sedation administration, colonoscopy completion rate, adenoma detection rate, and early complications rate in three cohorts: cohort A: intention for total colonoscopy cases; cohort B: cohort A excluding bowel obstruction cases; cohort C: CRC screening-surveillance cases within cohort B. We identified deficiencies and implemented our plan to optimize sedation. We prospectively evaluated its effects in both short- (Era 2) and long-term period (Era 3). Results. We identified that sedation administration and colonoscopy completion rates were below recommended standards. After sedation optimization its use rate increased significantly (38.1% to 55.8% to 69.5%) and colonoscopy completion rate increased from 88.3% to 90.6% to 96.4% in cohort B and from 93.2% to 95.3% to 98.3% in cohort C, in Eras 1, 2, and 3, respectively. Adenoma detection rate increased in cohort C (25.9% to 30.6% to 35%) and early complications rate decreased from 3.4% to 1.9% to 0.3%. Most endoscopists increased significantly their completion rate and this was preserved long-term. Conclusion. Increased sedation administration results in long-lasting improvement of colonoscopy quality indicators.

Serrated and adenomatous polyp detection increases with longer withdrawal time: results from the New Hampshire Colonoscopy Registry

OBJECTIVES

Detection and removal of adenomas and clinically significant serrated polyps (CSSPs) is critical to the effectiveness of colonoscopy in preventing colorectal cancer. Although longer withdrawal time has been found to increase polyp detection, this association and the use of withdrawal time as a quality indicator remains controversial. Few studies have reported on withdrawal time and serrated polyp detection. Using data from the New Hampshire Colonoscopy Registry, we examined how an endoscopist's withdrawal time in normal colonoscopies affects adenoma and serrated polyp detection.

METHODS

We analyzed 7,996 colonoscopies performed in 7,972 patients between 2009 and 2011 by 42 endoscopists at 14 hospitals, ambulatory surgery centers, and community practices. CSSPs were defined as sessile serrated polyps and hyperplastic polyps proximal to the sigmoid. Adenoma and CSSP detection rates were calculated based on median endoscopist withdrawal time in normal exams. Regression models were used to estimate the association of increased normal withdrawal time and polyp, adenoma, and CSSP detection.

RESULTS

Polyp and adenoma detection rates were highest among endoscopists with 9 min median normal withdrawal time, and detection of CSSPs reached its highest levels at 8-9 min. Incident rate ratios for adenoma and CSSP detection increased with each minute of normal withdrawal time above 6 min, with maximum benefit at 9 min for adenomas (1.50, 95% confidence interval (CI) (1.21, 1.85)) and CSSPs (1.77, 95% CI (1.15, 2.72)). When modeling was used to set the minimum withdrawal time at 9 min, we predicted that adenomas and CSSPs would be detected in 302 (3.8%) and 191 (2.4%) more patients. The increase in detection was most striking for the CSSPs, with nearly a 30% relative increase.

CONCLUSIONS

A withdrawal time of 9 min resulted in a statistically significant increase in adenoma and serrated polyp detection. Colonoscopy quality may improve with a median normal withdrawal time benchmark of 9 min.

Location, size, and distance: criteria for quality in esophagogastroduodenos copy reporting for pre-operative gastric cancer evaluation

BACKGROUND

There is a lack of existing literature regarding the quality of esophagogastroduodenoscopy (EGD) reporting for gastric cancer evaluation. This study aims to determine criteria for quality endoscopic evaluation of gastric cancer in North America by identifying important features of the EGD report for pre-operative evaluation of gastric cancer and assessing inclusion of these features in existing reports.

METHODS

Semi-structured interviews were conducted with experienced endoscopists from community and academic hospitals affiliated with the University of Toronto to identify essential elements for an EGD report. Then, 225 EGD reports from 2005 to 2008 were evaluated by two trained reviewers for inclusion of recommended EGD report elements and global assessment of report quality and adequacy for surgical planning.

RESULTS

Essential elements recommended by interviewed endoscopists include tumor size, location, and distance from gastroesophageal junction (GEJ). Approximately 95 % of all reports documented the location of lesions, <5 % documented distance from the GEJ, and <15 % documented tumor size. Overall report quality was rated as excellent for 4-5 % of reports; 20-42 % of all reports were deemed to be adequate for surgical planning. All surgeons interviewed as part of the endoscopist panel indicated that they would repeat the EGD before consulting with patients regarding surgical planning.

CONCLUSIONS

For pre-operative evaluation of gastric cancer, tumor size, location, and distance from key anatomical landmarks were proposed as essential elements of a quality EGD report. Most of the reviewed reports did not document these elements. Report quality is perceived to be poor and may lead to repeat endoscopy. Developing a standardized EGD reporting format based on inclusion of individual parameters can improve the quality of gastric cancer management.

The association between cecal insertion time and colorectal neoplasm detection

BACKGROUND

Information on the impact of cecal insertion time on colorectal neoplasm detection is limited. Our objective was to determine the association between cecal insertion time and colorectal neoplasm detection rate in colonoscopy screening.

METHODS

We performed a cross-sectional study of 12,679 consecutive subjects aged 40-79 years undergoing screening colonoscopy in routine health check-ups at the Center for Health Promotion of the Samsung Medical Center from December 2007 to June 2009. Fixed effects logistic regression conditioning on colonoscopist was used to eliminate confounding due to differences in technical ability and other characteristics across colonoscopists.

RESULTS

The mean cecal insertion time was 5.9 (SD, 4.4 minutes). We identified 4,249 (33.5%) participants with colorectal neoplasms, of whom 1,956 had small single adenomas (<5 mm), 595 had medium single adenomas (5-9 mm), and 1,699 had multiple adenomas or advanced colorectal neoplasms. The overall rates of colorectal neoplasm detection by quartiles of cecal insertion time were 36.8%, 33.4%, 32.7%, and 31.0%, respectively (p trend <0.001).The odds for small single colorectal adenoma detection was 16% lower (adjusted OR 0.84; 95% CI 0.71 to 0.99) in the fourth compared to the first quartile of insertion time (p trend 0.005). Insertion time was not associated with the detection rate of single adenomas ≥5 mm, multiple adenomas or advanced colorectal neoplasms.

CONCLUSION

Shorter insertion times were associated with increased rates of detection of small colorectal adenomas <5 mm. Cecal insertion time may be clinically relevant as missed small colorectal adenomas may progress to more advanced lesions.

Advanced adenoma detection rate is independent of nonadvanced adenoma detection rate

OBJECTIVES

Adenoma detection rate (ADR) is the accepted rate marker in colonoscopy quality. Advanced adenomas detected at index colonoscopy, while less frequent than nonadvanced adenomas, carry greater risk for future advanced neoplasia during surveillance colonoscopy. This study aimed to determine the effect of the colonoscopist and other factors on advanced ADR and to define the correlation of advanced and nonadvanced ADRs among colonoscopists.

METHODS

An observational study of a cohort of patients undergoing first-time colorectal cancer screening colonoscopy was conducted. Patient characteristics and colonoscopic findings were collected. Adenoma, advanced adenoma, and nonadvanced ADRs were calculated. Logistic regression was used to determine variable effects on advanced adenoma detection, and Spearman's rank-order correlation was used to evaluate the relationship between advanced and nonadvanced ADRs.

RESULTS

A total of 1,944 patients had first-time screening colonoscopies by 14 colonoscopists. All colonoscopists had adequate (>20%) ADRs. The variability in the colonoscopist ranges of detection was 22.22 to 44.66% for adenomas and 2.00 to 18.18% for advanced adenomas. Logistic regression showed that increasing patient age (odds ratio (OR) 1.16 per 5-year increase, 95% confidence interval (CI) 1.05-1.28, P=0.008) and male gender (OR 2.15, 95% CI 1.51-3.06, P<0.0001) were variables associated with advanced adenoma detection. Colonoscopists were significantly different in detecting advanced adenomas by random effects model (P=0.002), adjusting for patient age, gender, race, year of colonoscopy, gastroenterology fellow participation during colonoscopy, and nonadvanced adenomas. Spearman's rank-order correlation coefficient of -0.42 (95% CI -0.77 to 0.14, P=0.13) was not significant and showed no correlation between advanced and nonadvanced adenoma detection by the group of colonoscopists.

CONCLUSIONS

Advanced ADR is variable among colonoscopists with acceptable ADRs. Colonoscopists' advanced ADRs are independent of their nonadvanced ADRs.

Endoscopy and polyps-diagnostic and therapeutic advances in management

Despite multiple efforts aimed at early detection through screening, colon cancer remains the third leading cause of cancer-related deaths in the United States, with an estimated 51000 deaths during 2013 alone. The goal remains to identify and remove benign neoplastic polyps prior to becoming invasive cancers. Polypoid lesions of the colon vary widely from hyperplastic, hamartomatous and inflammatory to neoplastic adenomatous growths. Although these lesions are all benign, they are common, with up to one-quarter of patients over 60 years old will develop pre-malignant adenomatous polyps. Colonoscopy is the most effective screening tool to detect polyps and colon cancer, although several studies have demonstrated missed polyp rates from 6%-29%, largely due to variations in polyp size. This number can be as high as 40%, even with advanced (> 1 cm) adenomas. Other factors including sub-optimal bowel preparation, experience of the endoscopist, and patient anatomical variations all affect the detection rate. Additional challenges in decision-making exist when dealing with more advanced, and typically larger, polyps that have traditionally required formal resection. In this brief review, we will explore the recent advances in polyp detection and therapeutic options.

Quality colonoscopy: A matter of time, technique or technology?

Quality colonoscopy is defined by the detection of adenomatous polyps at least 25% of the time in men and 15% of the time in women. Recent studies highlight the importance of key aspects of high quality colonoscopy. These include the amount of time spent examining the mucosa or withdrawal time, the quality of withdrawal technique and new technologies which seek to maximize the detection of colonic neoplasia. This review summarizes the latest evidence regarding the role of time, technique and technology in shaping the quality of colonoscopy.

An endoscopic quality improvement program improves detection of colorectal adenomas

OBJECTIVES

Adenoma detection rate (ADR) is a key measure of quality in colonoscopy. Low ADRs are associated with development of interval cancer after "negative" colonoscopy. Uncontrolled studies mandating longer withdrawal time, and other incentives, have not significantly improved ADR. We hypothesized that an endoscopist training program would increase ADRs.

METHODS

Our Endoscopic Quality Improvement Program (EQUIP) was an educational intervention for staff endoscopists. We measured ADRs for a baseline period, then randomly assigned half of the 15 endoscopists to undergo EQUIP training. We then examined baseline and post-training study ADRs for all endoscopists (trained and un-trained) to evaluate the impact of training. A total of 1,200 procedures were completed in each of the two study phases.

RESULTS

Patient characteristics were similar between randomization groups and between study phases. The overall ADR in baseline phase was 36% for both groups of endoscopists. In the post-training phase, the group of endoscopists randomized to EQUIP training had an increase in ADR to 47%, whereas the ADR for the group of endoscopists who were not trained remained unchanged at 35%. The effect of training on the endoscopist-specific ADRs was estimated with an odds ratio of 1.73 (95% confidence interval 1.24-2.41, P=0.0013).

CONCLUSIONS

Our results indicate that ADRs can be improved considerably through simple educational efforts. Ultimately, a trial involving a larger number of endoscopists is needed to validate the utility of our training methods and determine whether improvements in ADRs lead to reduced colorectal cancer.

Relationship between detection of adenomas by flexible sigmoidoscopy and interval distal colorectal cancer

BACKGROUND & AIMS

Low rates of adenoma detection by colonoscopy have been associated with increased rates of interval colorectal cancer. We evaluated the relationship between the rate of adenoma detection by flexible sigmoidoscopy and interval distal colorectal cancer.

METHODS

We analyzed data from the Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer screening trial, which used flexible sigmoidoscopy as a colorectal cancer screening modality (46,835 subjects; 66,711 examinations by 93 examiners). An adenoma detection rate was defined for each examiner as the number of examinations that identified adenomas (confirmed by pathology analysis) divided by the total number of screening examinations. Interval cancers were defined as cancers presumed detectable but not detected, which was based on the stage at diagnosis and the elapsed time from screening to diagnosis.

RESULTS

The Prostate, Lung, Colorectal, and Ovarian Cancer study identified 32 interval distal cancers. The incidence of interval cancer for individuals screened by examiners in the lowest quartile of distal adenoma detection (2.0%-7.2%) was 9.0/10,000 examinations, whereas the incidence of interval cancers was lower among individuals whose examiners were in higher quartiles of adenoma detection, ranging from 3.0 to 5.4/10,000 examinations. The odds of interval distal cancer were significantly increased for patients of examiners in the lowest quartile of distal adenoma detection (<7.2%), with an adjusted odds ratio of 2.4 (95% confidence interval, 1.1-5.0; P = .02).

CONCLUSIONS

Lower levels of adenoma detection by flexible sigmoidoscopy increase the risk for interval distal cancer. Detection of distal adenomas is a marker of the performance quality of flexible sigmoidoscopy.

Sedation in screening colonoscopy: impact on quality indicators and complications

OBJECTIVES

Quality indicators including cecal intubation rate (CIR) and adenoma detection rate (ADR) are established. Sex differences of quality indicators are observed, but the influence of sedation has not been investigated so far. The objective of this study is to assess the impact of sedation on quality indicators, including CIR and ADR, according to sex.

METHODS

We analyzed data of 52,506 screening colonoscopies performed by 196 endoscopists between November 2007 and April 2011 according to the Austrian "quality management for colon cancer prevention" program.

RESULTS

Sedation did not affect polyp detection rate (women P=0.7972, men P=0.3711) or ADR for both sexes (women P=0.2773, men P=0.8676). ADR was not significantly influenced by sedation (P=0.1272), but by age and sex (both P<0.0001), when the executing endoscopist was considered. Although women were more often sedated than men (90.70 vs. 81.83%; P<0.0001), CIR was slightly lower in women than in men (94.69 vs. 96.58%; P<0.0001). Sedation improved the CIR in women by 2.95% (94.96 vs. 92.01%; P<0.0001), whereas in men it was just by 1.28% (96.81 vs. 95.53%; P<0.0001). Sedated women only reached the CIR of unsedated men (94.96 vs. 95.53%; P=0.1005). Accounting for the intra-observer influence of the endoscopist, the overall CIR was influenced by the interaction of sex and age (P=0.0049), but not by sedation (P=0.1435).

CONCLUSIONS

Sedation does not increase adenoma or polyp detection, although it leads to an increase in CIR in men and women. This effect is more pronounced in women, yet CIR of men remains higher compared with women. Quality indicators are mainly influenced by the patient's age, sex, and the endoscopists' individual performance, rather than the endoscopists' subspeciality or procedural experience.

Quality audit of colonoscopy reports amongst patients screened or surveilled for colorectal neoplasia

AIM: To complete a quality audit using recently published criteria from the Quality Assurance Task Group of the National Colorectal Cancer Roundtable.

METHODS: Consecutive colonoscopy reports of patients at average/high risk screening, or with a prior colorectal neoplasia (CRN) by endoscopists who perform 11 000 procedures yearly, using a commercial computerized endoscopic report generator. A separate institutional database providing pathological results. Required documentation included patient demographics, history, procedure indications, technical descriptions, colonoscopy findings, interventions, unplanned events, follow-up plans, and pathology results. Reports abstraction employed a standardized glossary with 10% independent data validation. Sample size calculations determined the number of reports needed.

RESULTS: Two hundreds and fifty patients (63.2 ± 10.5 years, female: 42.8%, average risk: 38.5%, personal/family history of CRN: 43.3%/20.2%) were scoped in June 2009 by 8 gastroenterologists and 3 surgeons (mean practice: 17.1 ± 8.5 years). Procedural indication and informed consent were always documented. 14% provided a previous colonoscopy date (past polyp removal information in 25%, but insufficient in most to determine surveillance intervals appropriateness). Most procedural indicators were recorded (exam date: 98.4%, medications: 99.2%, difficulty level: 98.8%, prep quality: 99.6%). All reports noted extent of visualization (cecum: 94.4%, with landmarks noted in 78.8% - photodocumentation: 67.2%). No procedural times were recorded. One hundred and eleven had polyps (44.4%) with anatomic location noted in 99.1%, size in 65.8%, morphology in 62.2%; removal was by cold biopsy in 25.2% (cold snare: 18%, snare cautery: 31.5%, unrecorded: 20.7%), 84.7% were retrieved. Adenomas were noted in 24.8% (advanced adenomas: 7.6%, cancer: 0.4%) in this population with varying previous colonic investigations.

CONCLUSION: This audit reveals lacking reported items, justifying additional research to optimize quality of reporting.

Diagnostic yield of small bowel capsule endoscopy depends on the small bowel transit time

AIM: To investigate whether the small bowel transit time (SBTT) influences the diagnostic yield of capsule endoscopy (CE).

METHODS: Six hundred and ninety-one consecutive CE procedures collected in a database were analyzed. SBTT and CE findings were recorded. A running mean for the SBTT was calculated and correlated to the diagnostic yield with a Spearman’s correlation test. Subgroup analyses were performed for the various indications for the procedure.

RESULTS: There was a positive correlation between the diagnostic yield and SBTT (Spearman’s rho 0.58, P < 0.01). Positive correlations between diagnostic yield and SBTT were found for the indication obscure gastrointestinal bleeding (r = 0.54, P < 0.01), for polyposis and carcinoid combined (r = 0.56, P < 0.01) and for the other indications (r = 0.90, P <0.01), but not for suspected Crohn’s disease (r = -0.40).

CONCLUSION: The diagnostic yield in small bowel capsule endoscopy is positively correlated with the small bowel transit time. This is true for all indications except for suspected Crohn’s disease.

Quality evaluation of colonoscopy reporting and colonoscopy performance in daily clinical practice

BACKGROUND

Comprehensive monitoring of colonoscopy quality requires complete and accurate colonoscopy reporting.

OBJECTIVE

This study aimed to assess the compliance with colonoscopy reporting and to assess the quality of colonoscopy performance.

DESIGN

Consecutive colonoscopy reports were reviewed by hand. Four hundred reports were included from each department.

SETTING

Daily clinical practice in 12 Dutch endoscopy departments.

PATIENTS

Consecutive patients undergoing scheduled colonoscopy procedures.

MAIN OUTCOME MEASUREMENTS

Quality of reporting was assessed by using the American Society for Gastrointestinal Endoscopy criteria for colonoscopy reporting. Quality of colonoscopy performance was evaluated by using the cecal intubation rate and adenoma detection rate (ADR).

RESULTS

A total of 4800 colonoscopies were performed by 116 endoscopists: 70% by gastroenterologists, 16% by gastroenterology fellows, 10% by internists, 3% by nurse-endoscopists, and 1% by surgeons. The mean age of the patients was 59 years (standard deviation 16), and 47% were male. Reports contained information on indication, sedation practice, and extent of the procedure in more than 90%. Only 62% of the reports mentioned the quality of bowel preparation (range between departments 7%-100%); photographic documentation of the cecal landmarks was present in 71% (range 22%-97%). The adjusted cecal intubation rate was 92% (range 84%-97%). The ADR was 24% (range 13%-32%).

LIMITATIONS

Dependent on reports, no intervention in endoscopic practice. No analysis for performance per endoscopist.

CONCLUSION

Colonoscopy reporting varied significantly in clinical practice. Colonoscopy performance met the suggested standards; however, considerable variability between endoscopy departments was found. The results of this study underline the importance of the implementation of quality indicators and guidelines. Moreover, by continuous monitoring of quality parameters, the quality of both colonoscopy reporting and colonoscopy performance can easily be improved.

MiraLAX vs. Golytely: is there a significant difference in the adenoma detection rate?

BACKGROUND

In recent clinical trials (RCT) of bowel preparation, Golytely was more efficacious than MiraLAX. We hypothesised that there is a difference in adenoma detection between Golytely and MiraLAX.

AIMS

To compare the adenoma detection rate (ADR) between these bowel preparations, and to identify independent predictors of bowel preparation quality and adenoma detection.

METHODS

This was a post hoc analysis of an RCT that assessed efficacy and patient tolerability of Golytely vs. MiraLAX/Gatorade in average risk screening colonoscopy patients. Bowel preparation quality was measured with the Boston Bowel Preparation Scale (BBPS). An excellent/good equivalent BBPS score was defined as ≥ 7. Polyp pathology review was performed. ADR was defined as the proportion of colonoscopies with an adenoma. Univariate and multivariate analyses were conducted.

RESULTS

One hundred and ninety patients were prospectively enrolled (87 MiraLAX, 103 Golytely). Golytely had a higher rate of a BBPS score ≥ 7 (82.5% vs. MiraLAX 67.8%, P=0.02). The ADR in the Golytely cohort was 26.2% (27/103), and was 16.1% (14/87) for MiraLAX (P = 0.091). On multivariate analyses, Golytely was 2.13 × more likely to be associated with a BBPS ≥ 7 (95% CI 1.05-4.32, P = 0.04) and 2.28 × more likely to be associated with adenoma detection (95% CI 1.05-4.98, P = 0.04) than MiraLAX.

CONCLUSIONS

Golytely was more efficacious than MiraLAX in bowel cleansing, and was independently associated with both bowel prep quality (BBPS ≥ 7) and higher adenoma detection. Golytely should be used as first line for bowel prep for colonoscopy. Studies with larger populations are needed to confirm these results.

Current status of chromoendoscopy and narrow band imaging in colonoscopy

Colonoscopy, the preferred procedure for colon cancer screening, has well-documented limitations. To improve colonoscopy's effectiveness, augmented endoscopy techniques, such as chromoendoscopy and narrow band imaging (NBI) have been evaluated. Both techniques are inexpensive, safe, and relatively easy to perform. Chromoendoscopy has an increasingly important role in surveillance of IBD, but significant work is needed to determine the optimal staining techniques and mucosal surface pattern analysis before this technique can be incorporated into routine clinical practice. NBI is a much newer technology with far less data. Well-designed prospective randomized controlled trials have failed to identify a benefit of NBI in screening colonoscopy, in surveillance for high-risk populations or as an adjunct for therapeutic procedures.

Time of day variation in polyp detection rate for colonoscopies performed on a 3-hour shift schedule

BACKGROUND

Recent research suggests that the colonoscopy polyp detection rate (PDR) varies by time of day, possibly because of endoscopist fatigue. Mayo Clinic Rochester (MCR) schedules colonoscopies on 3-hour shifts, which should minimize fatigue.

OBJECTIVE

To examine PDR variation with the MCR shift schedule.

DESIGN

Retrospective cohort.

SETTING

Outpatient tertiary-care center.

PATIENTS

This study involved completed outpatient colonoscopies in 2008. Procedures were excluded for lack of withdrawal time stamps, indications other than average-risk screening, inadequate bowel preparation, fellow participation, or performance by endoscopists with a low number of endoscopies performed.

INTERVENTION

None.

MAIN OUTCOME MEASUREMENTS

PDR (colonoscopies with ≥1 polyp divided by total number of colonoscopies) by shift of day.

RESULTS

We analyzed 3846 colonoscopies. PDR varied significantly by shift (P = .008) on univariate analysis; results for shifts 1 and 3 were similar (39.0% vs 38.7%, respectively) whereas shift 2 had the highest PDR (44.7%). Mean withdrawal times were stable (P = .92). PDR also varied significantly (P < .0001) by month of year on univariate analysis. On multivariate analysis, patient age (P < .0001), patient gender (P < .0001), endoscopist mean withdrawal time (P < .0001), month of year (P = .0002), endoscopist experience (P = .04), and shift of day (P = .048) significantly predicted PDR.

LIMITATIONS

Retrospective study.

CONCLUSION

MCR's 3-hour shift schedule does not show a decrease in PDR as the day progresses, as seen in other recent studies. Intervention trials at other institutions could determine whether alterations in shift length lead to PDR improvements.

Quality measures and credentialing in gastrointestinal endoscopy

PURPOSE OF REVIEW

Quality assessment and improvement are now mainstream activities in medicine. This review presents recent publications pertaining to quality, proposed quality measures, and associated topics in credentialing and delivery of endoscopic services.

RECENT FINDINGS

The literature continues to focus primarily on colonoscopy services. Surveillance colonoscopy continues to suffer from underuse in high-risk patients and overuse in average to moderate-risk patients, based upon current guidelines for application. Several series update and add to our understanding of adenoma detection rates as measures of quality. One study confirmed an inverse association between adenoma detection rates at screening endoscopy and the risk for identification of colorectal cancer at a subsequent diagnostic or surveillance procedure. Credentialing guidelines proposed for worldwide application are becoming uniform and similar to those from several national societies. Quality measures for use in endoscopic ultrasonography and endoscopic retrograde cholangiopancreatography are just beginning to be assessed in large series.

SUMMARY

Proposed quality measures for colonoscopy are maturing, with increasing emphasis on adenoma detection rates rather than indirect proxies for neoplasia detection. Personal and unit-based benchmarking appears to be gaining favor and is facilitated by use of automated reporting systems. Greater attention is being focused on individual performance and assuring competence of the endoscopy workforce.

[Quality colonoscopy: assumptions and expectations]

Colonoscopy has become accepted as the most effective method of screening of the colon for neoplasia. Evidences prove that utilization of colonoscopy has increased dramatically in the past few years, largely because of increased rates of CRC screening. Effectiveness and safety of colonoscopy depend on the quality of examination, and growing body of evidence suggests that the quality of colonoscopy varies in clinical practice. Quality assurance of colonoscopy could be expected to contribute significantly to improved patient care. There is a clear need for evidence-based quality measures to ensure the quality of colonoscopy. In this review we present an overview of literature concerning criteria for best practice and important quality indicators for colonoscopy.