Experience of the endoscopist increases detection rates of smaller size and higher histological grade polyps

Artificial intelligence and colonoscopy experience: lessons from two randomised trials

BACKGROUND AND AIMS

Artificial intelligence has been shown to increase adenoma detection rate (ADR) as the main surrogate outcome parameter of colonoscopy quality. To which extent this effect may be related to physician experience is not known. We performed a randomised trial with colonoscopists in their qualification period (AID-2) and compared these data with a previously published randomised trial in expert endoscopists (AID-1).

METHODS

In this prospective, randomised controlled non-inferiority trial (AID-2), 10 non-expert endoscopists (<2000 colonoscopies) performed screening/surveillance/diagnostic colonoscopies in consecutive 40-80 year-old subjects using high-definition colonoscopy with or without a real-time deep-learning computer-aided detection (CADe) (GI Genius, Medtronic). The primary outcome was ADR in both groups with histology of resected lesions as reference. In a post-hoc analysis, data from this randomised controlled trial (RCT) were compared with data from the previous AID-1 RCT involving six experienced endoscopists in an otherwise similar setting.

RESULTS

In 660 patients (62.3±10 years; men/women: 330/330) with equal distribution of study parameters, overall ADR was higher in the CADe than in the control group (53.3% vs 44.5%; relative risk (RR): 1.22; 95% CI: 1.04 to 1.40; p<0.01 for non-inferiority and p=0.02 for superiority). Similar increases were seen in adenoma numbers per colonoscopy and in small and distal lesions. No differences were observed with regards to detection of non-neoplastic lesions. When pooling these data with those from the AID-1 study, use of CADe (RR 1.29; 95% CI: 1.16 to 1.42) and colonoscopy indication, but not the level of examiner experience (RR 1.02; 95% CI: 0.89 to 1.16) were associated with ADR differences in a multivariate analysis.

CONCLUSIONS

In less experienced examiners, CADe assistance during colonoscopy increased ADR and a number of related polyp parameters as compared with the control group. Experience appears to play a minor role as determining factor for ADR.

TRIAL REGISTRATION NUMBER

NCT:04260321.

The analysis of multilevel factors affecting adenoma detection rates for colonoscopies: a large-scale retrospective study

BACKGROUND

Adenoma detection rate (ADR) is a validated primary quality indicator for colonoscopy procedures. However, there is growing concern over the variability associated with ADR indicators. Currently, the factors that influence ADRs are not well understood.

AIMS

In this large-scale retrospective study, the impact of multilevel factors on the quality of ADR-based colonoscopy was assessed.

METHODS

A total of 10,788 patients, who underwent colonoscopies performed by 21 endoscopists between January 2019 and December 2019, were retrospectively enrolled in this study. Multilevel factors, including patient-, procedure-, and endoscopist-level characteristics were analyzed to determine their relationship with ADR.

RESULTS

The overall ADR was 20.21% and ranged from 11.4 to 32.8%. Multivariate regression analysis revealed that higher ADRs were strongly correlated with the following multilevel factors: patient age per stage (OR 1.645; 95% CI 1.577-1.717), male gender (OR 1.959; 95% CI 1.772-2.166), sedation (OR 1.402; 95% CI 1.246-1.578), single examiner colonoscopy (OR 1.330; 95% CI 1.194-1.482) and senior level endoscopists (OR 1.609; 95% CI 1.449-1.787).

CONCLUSION

The ADR is positively correlated with senior level endoscopists and single examiner colonoscopies in patients under sedation. As such, these procedure- and endoscopist-level characteristics are important considerations to improve the colonoscopy quality.

Adenoma detection rate as a quality indicator for colonoscopy: a descriptive cross-sectional study from a tertiary care hospital in Pakistan

Background and study aims  Adenoma detection rate (ADR) is validated for measuring quality of colonoscopy, however there is lack of colorectal cancer (CRC) screening program in South Asia. The purpose of this study is to analyze and review the polyp detection rate (PDR) and ADR and provide insight into the factors that influence them in Pakistan. Patients and methods  This retrospective, cross-sectional study was performed at the Aga Khan University Hospital, Karachi, Pakistan, on patients ≥ 18 years, who underwent colonoscopy between January 1, 2017 and June 30, 2018. Results  Of 1985 patients, 59 % were male and 41 % female, with mean age of 47.8 ± 16.2 years. The most common indication for colonoscopy was bleeding-per-rectum (28.0 %) and overall PDR and ADR were 17.9 % and 9.9 %, respectively. There was no significant difference between genders for either PDR ( P  = 0.378) or ADR ( P  = 0.574). Significantly higher PDR and ADR were found for patients ≥ 50 years ( P  < 0.001), as well as for suboptimal bowel preparation [PDR (25.7 %; P  = 0.007) and ADR (18.6 %; P  = 0.014)]. Interestingly, endoscopists with < 500 colonoscopy-procedural-experience reported a higher PDR (21.6 %; P  = 0.020) and ADR (14.4 %; P = 0.049), corresponding to a significantly higher PDR (20.6 %; P  = 0.005) and ADR (11.7 %; P  = 0.02) for endoscopists in practice for ≤ 10 years. Conclusions  We have noticed low PDR and ADR, which require further investigation and research. In addition, we believe there should be a different baseline ADR and PDR as a quality indicator for colonoscopy in our region, where no internationally recommended colonoscopic screening programs have been implemented.

A review of water exchange and artificial intelligence in improving adenoma detection

Water exchange (WE) and artificial intelligence (AI) have made critical advances during the past decade. WE significantly increases adenoma detection and AI holds the potential to help endoscopists detect more polyps and adenomas. We performed an electronic literature search on PubMed using the following keywords: water-assisted and water exchange colonoscopy, adenoma and polyp detection, artificial intelligence, deep learning, neural networks, and computer-aided colonoscopy. We reviewed relevant articles published in English from 2010 to May 2020. Additional articles were searched manually from the reference lists of the publications reviewed. We discussed recent advances in both WE and AI, including their advantages and limitations. AI may mitigate operator-dependent factors that limit the potential of WE. By increasing bowel cleanliness and improving visualization, WE may provide the platform to optimize the performance of AI for colonoscopies. The strengths of WE and AI may complement each other in spite of their weaknesses to maximize adenoma detection.

Association Between Endoscopist Annual Procedure Volume and Colonoscopy Quality: Systematic Review and Meta-analysis

BACKGROUND & AIMS

In addition to monitoring adverse events (AEs) and post-colonoscopy colorectal cancers (PCCRC), indicators for assessing colonoscopy quality include adenoma detection rate (ADR) and cecal intubation rate (CIR). It is unclear whether there is an association between annual colonoscopy volume and ADR, CIR, AEs, or PCCRC.

METHODS

We searched publication databases through March 2019 for studies assessing the relationship between annual colonoscopy volume and outcomes, including ADR, CIR, AEs, or PCCRC. Pooled odds ratios (ORs) were calculated using DerSimonian and Laird random effects models. Sensitivity analyses were performed to assess for potential methodological or clinical factors associated with outcomes.

RESULTS

We performed a systematic review of 9235 initial citations, generating 27 retained studies comprising 11,276,244 colonoscopies. There was no association between procedural volume and ADR (OR, 1.00; 95% CI, 0.98-1.02 per additional 100 annual procedures). CIR improved with each additional 100 annual procedures (OR, 1.17; 95% CI, 1.08-1.28). There was a non-significant trend toward decreased overall AEs per additional 100 annual procedures (OR, 0.95; 95% CI, 0.90-1.00). There was considerable heterogeneity among most analyses.

CONCLUSIONS

In a systematic review and meta-analysis, we found higher annual colonoscopy volumes to correlate with higher CIR, but not with ADR or PCCRC. Trends toward fewer AEs were associated with higher annual colonoscopy volumes. There are few data available from endoscopists who perform fewer than 100 annual colonoscopies. Studies are needed on extremes in performance volumes to more clearly elucidate associations between colonoscopy volumes and outcomes.

Factors associated with oesophagogastric cancers missed by gastroscopy: a case-control study

INTRODUCTION

There is increasing demand for gastroscopy in the United Kingdom. In around 10% of patients, gastroscopy is presumed to have missed oesophagogastric (OG) cancer prior to diagnosis. We examine patient, endoscopist and service level factors that may affect rates of missed OG cancers.

METHODS

Gastroscopies presumed to have missed OG cancers performed up to 3 years prior to diagnosis were identified over 6 years in Sheffield, UK. Factors related to the patient, endoscopist and endoscopy lists were examined in a case-control study. Procedures which missed cancer were compared with two procedure controls: the procedures which subsequently diagnosed cancer in the same patient, and second, endoscopist matched procedures diagnostic of small benign focal lesions.

RESULTS

We identified 48 (7.7%) cases of missed OG cancer. Endoscopy lists on which OG cancer diagnoses were missed contained a greater number of total procedures compared with lists on which diagnoses were subsequently made (OR 1.42 95% CI 1.13 to 1.78) and when compared with lists during which matched endoscopists diagnosed benign small focal lesions (OR 1.25, 95% CI 1.02 to 1.52). The use of sedation, endoscopist profession and experience, or time of procedure were not associated with a missed cancer.

CONCLUSION

7.7% of patients diagnosed with OG cancer could have been diagnosed and treated earlier. Our study suggests that endoscopy lists with greater numbers of procedures may be associated with missed OG cancers. The use of sedation, endoscopist background or time of procedure did not increase the risk of missed cancer procedures.

Risk factors associated with the detection and missed diagnosis of colorectal flat adenoma: a Chinese multicenter observational study

OBJECTIVES

Flat colorectal adenomas have a high risk of malignancy; however, their detection is often difficult due to their flat morphology. In this retrospective, large-scale study, we investigated the prevalence and characteristics of flat adenomas in a population in China.

METHODS

We analyzed the data collected for 16951 consecutive patients who underwent colonoscopy at four participating hospitals between September 2013 and September 2015. All colonoscopies were performed without magnification.

RESULTS

Among the 1,6951 patients, 2938 (17.3%) had adenoma and 796 (4.7%) had flat adenomas. The detection of flat adenoma showed a weak correlation with the detection of adenoma (r = 0.666). Multivariable logistic regression analysis revealed the following independent factors influencing the detection of flat adenomas: patient-related factors of age, presence of warning symptoms, history of adenomas and bowel preparation as well as endoscopist-related factors of endoscopist's level of proficiency, number of colonoscopy operators and withdrawal time.

CONCLUSIONS

The prevalence of flat adenomas in our study on Chinese patients was consistent with that reported from other countries. Factors conducive to the detection of flat adenomas were patient age of > 60 years, warning symptoms, history of adenoma, good bowel preparation, experienced endoscopist, single-operator colonoscopy and colonoscopy withdrawal time of >6 min.

The evaluation of three treatment protocols using oral prednisone and oral meloxicam for therapy of canine idiopathic lymphoplasmacytic rhinitis: a pilot study

Background

Idiopathic lymphoplasmacytic rhinitis (LPR) is a common inflammatory disorder of the nasal cavity in dogs due to unknown etiology. It is characterised by non-specific clinical signs, including nasal discharge, epistaxis and breathing problems. Diagnosis is usually based on the histopathologic identification of infiltrating plasmocytes and lymphocytes in the nasal mucosa and the exclusion of other underlying diseases. Treatment strategies include glucocorticoids, non-steroidal anti-inflammatory drugs, antibiotics and antifungal medications. The aim of this study was to evaluate the efficacy of various therapeutic protocols for managing canine lymphoplasmacytic rhinitis based on the results of clinical, endoscopic and histological examinations, and to determine the relapse rate for LPR in dogs.

Twenty dogs of different breeds and both sexes, aged 1 to 14 years, were divided into four groups, each consisting of five dogs, including three experimental groups diagnosed with LPR and a control group.

The dogs from the first experimental group were administered prednisone orally at 1 mg/kg/day in the first 4 weeks and 0,5 mg/kg/day in the following 2 weeks. The second group of dogs was administered meloxicam orally at 0,1 mg/kg/day in the first 3 weeks, followed by prednisone at 1 mg/kg/day in the following 2 weeks and 0,5 mg/kg/day in the last week of the treatment. The dogs from the third experimental group were administered meloxicam orally at 0,1 mg/kg/day for 6 weeks. The control group of dogs was administered empty gelatin capsules (placebo) orally for 6 weeks. Clinical signs, endoscopic and histopathologic lesions were scored before and after treatment. Groups were compared using Chi- squared statistics in a 2 × 2 table for pre- versus post-treatment scores.

Results

Clinical signs persisted in the group treated with meloxicam and were mostly resolved in prednisone-treated dogs. However, endoscopic and histological changes were still observed in these two groups after treatment. The severity of all diagnostic features was reduced in the group treated with meloxicam for 3 weeks followed by prednisone for 3 weeks. The significant differences (p < 0.05) were noted between experimental and control groups. The dogs showed a statistically significant reduction in characteristics of the LPR before and after treatment, as measured by clinical signs (Group 1vs.4 p = 0.00, group 2 vs 4 p = 0.00, group 3 vs 4 p = 0,01), by endoscopy (1 vs 4 p = 0,01, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03), and by histopathology (groups 1 vs 4 p = 0,00, 2 vs 4 p = 0,00, 3 vs 4 p = 0,03). The significant differences were noted between experimental groups, as measured by endoscopy (group 2vs 3 p = 0,04), and by relapse rate (groups 1 and 2 p = 0,03, groups 2 and 3 p = 0,01).

Conclusions

The three treatment protocols administered to dogs improved clinical, endoscopic and histological status. However, oral administration of meloxicam for 3 weeks, followed by prednisone for 3 weeks, appeared to be the most successful treatment. These patients remained asymptomatic for 6 months.

Association between endoscopic findings related to colonic diverticula and bowel habits: A multicenter study in Japan

BACKGROUND AND AIM

Few studies have shown the associations between colonic diverticula and endoscopic findings such as location, inflammation, number of diverticula, sigmoid colon rigidity, and bowel habits.

METHODS

Japanese subjects who underwent total colonoscopies at six centers in Japan from November 2015 to October 2016 were analyzed. Bowel habits were evaluated using the Gastrointestinal Symptom Rating Scale. Location and number of diverticula, inflammation, and sigmoid colon rigidity were evaluated from endoscopy results.

RESULTS

A total of 762 subjects (486 men and 276 women [ratio, 1.76:1]) whose mean age was 65.5 ± 11.4 years were evaluated. In multivariate analysis, presence of constipation was associated with a significantly lower likelihood of left-sided colonic diverticula (odds ratio = 0.40, 95% confidence interval 0.20-0.82, P = 0.012), whereas right-sided and bilateral-sided colonic diverticula, multiple colonic diverticula, inflammation findings, and sigmoid colon rigidity were not related to bowel habits.

CONCLUSIONS

Among endoscopic findings related to colonic diverticula and bowel habits, only left-sided colonic diverticula were inversely associated with constipation, whereas inflammation findings, multiple diverticula, and sigmoid colon rigidity were not related to bowel habits. However, the association of inflammation findings with colonic diverticula and bowel habits should be further studied. Investigation of changes in left-sided colonic diverticula may lead to new treatments for constipation.

ADENOMA DETECTION RATE EVALUATION AND QUALITY OF COLONOSCOPY IN THE CENTER-WEST REGION OF BRAZIL

BACKGROUND

Colorectal cancer is the third commonest cancer in men and the second in women worldwide. Peculiarities of its evolution allow secondary prevention measures through colonoscopy, with high diagnostic and therapeutic capacity. In this context, the quality indicators of the procedure become important, among them the adenoma detection rate (ADR).

OBJECTIVE

To relate the ADR in a medium risk population subjected to colonoscopy with sociodemographic, technical and histopathological indicators.

METHODS

This was a descriptive, observational and retrospective study whose data were collected from medical records of colonoscopy exams with the indication of colorectal cancer screening or prevention in the period from August to October 2016.

RESULTS

A total of 436 exams were included for analysis. Female sex represented 66.3% with 289 patients versus 33.7% for men. Patients aged between 50 and 59 years were 223 (51.1%) and those between 60 and 75 years were 213 (48.9%). In 99 exams (22.7%) chromoscopy was used, and 420 patients (96.3%) were adequately prepared. There were 118 patients with adenomas, resulting in an overall ADR of 27.1%. The ADR for men was 30.6% and 25.3% for women. Patients between 60 and 75 years old had a significantly higher ADR (31.9%, compared to 22.4% of the younger ones). Examinations in which chromoscopy was used also presented higher ADR.

CONCLUSION

The ADR values found for the population of the studied region were compatible with internationally established goals. Continuous evaluation of the ADR may yield interventions aimed at improving quality standards for colonoscopy and promote better prevention of colorectal cancer.

Annual colonoscopy volume and maintenance of competency for surgeons

INTRODUCTION

To determine whether the annual case volume of general surgeons (greater or less than 200 colonoscopies) is associated with quality outcomes.

METHODS

This retrospective cohort study involved all adults who underwent colonoscopy by a surgeon in the city of St. John's, NL, during the first 6 months of 2012. Subjects were identified through records from the health authority, and data were recorded on a standardized data sheet. Univariate analysis followed by stepwise multivariable logistic regression was performed to determine whether there was an association between quality outcomes (colonoscopy completion rate, adenoma detection rate) and predictors of these outcomes including annual colonoscopy volume, patient age, gender, indication for colonoscopy, and ASA score. A Chi-squared test was used to determine whether other outcomes were associated with annual colonoscopy volume.

RESULTS

Data were collected on 1060 patients. Mean age was 59.5 (sd 12.2) years with 550 females. A total of 13 surgeons were studied, of which 7 performed less than 200 annual colonoscopies over the previous 2 years (low-volume group) and 6 performed more than 200 annual colonoscopies over the previous 2 years (high-volume group). While there was a significant difference in the colonoscopy completion rate favoring the high-volume group (82.2 vs. 91.1 %, p < 0.001), no difference was noted in the adenoma detection rate between groups (16.7 vs. 17.7 %, p = 0.762). The regression model revealed that colonoscopy completion was also associated with an indication of screening or surveillance and an ASA score of 1 or 2. The adenoma detection rate was associated with older age and male gender. There was no statistically significant association between annual colonoscopy volume and other safety outcome measures.

CONCLUSION

Performing over 200 colonoscopies annually is associated with higher colonoscopy completion rates, but does not appear to be associated with other quality measures.

Colonoscopy without sedation: Patient factors alone are less likely to influence its uptake

BACKGROUND AND STUDY AIMS

Conscious sedation during colonoscopy minimizes discomfort, improves polyp detection rates, and reduces technical failure, but carries medication-related risks and requires dedicated and costly recovery services. Sedation-free procedures may offer a safer alternative. We aimed to compare this group with those receiving sedation to determine differences in patient characteristics, cecal intubation rates, polyp detection rates, discomfort levels and safety in patients for whom anesthesia is high risk.

PATIENTS AND METHODS

Prospectively collected data from all colonoscopies performed over a 1-year period at three district general hospitals were analyzed. Conscious sedation was offered to all patients and outcomes in those who refused were compared with outcomes in those who received sedation.

RESULTS

One hundred ninety-four of 1694 (11 %) colonoscopies were performed without sedation (61 % male, P < 0.001) but rates varied between hospitals. Of these, 55 % were American Society of Anesthesiologists (ASA) grade 3 or more and 5 % experienced moderate discomfort, compared to 40 % (P < 0.0001) and 10 % (P = 0.023) respectively of those receiving sedation. They were more likely to have indications of rectal bleeding or frequency of stool and less likely to have anaemia or macroscopic inflammation at colonoscopy. Complications, completion. and polyp detection rates were similar in both groups.

CONCLUSIONS

Colonoscopy without sedation can be completed successfully in select patients without compromising comfort or polyp detection rates and is safe in those for whom anesthesia is high risk. It is therefore a safe alternative for clinicians concerned about sedation, but the findings suggest that hospital, rather than patient factors, may prevent its uptake.

Effect of Colonoscopy Volume on Quality Indicators

Background. The purpose of this study is to determine if colonoscopy quality is associated with the annual case volume of endoscopists. Methods. A retrospective cohort study was performed on 3235 patients who underwent colonoscopy in the city of St. John's, NL, between January and June 2012. Data collected included completion of colonoscopy (CCR) and adenoma detection rates (ADR). Endoscopists were divided into quintiles based on annual case volume. To account for potential confounding variables, univariate analyses followed by multivariable logistic regression were used to identify variables independently associated with CCR and ADR. Results. A total of 13 surgeons and 8 gastroenterologists were studied. There was a significant difference in CCR (p < 0.001) and ADR (p < 0.001) based on annual volume. Following multivariable regression, predictors of successful colonoscopy completion included annual colonoscopy volume, lower age, male sex, an indication of screening or surveillance, and a low ASA score. Predictors of adenoma detection included older age, male sex, an indication of screening or surveillance, and gastroenterology specialty. Conclusion. Higher annual case volume is associated with better quality of colonoscopy in terms of completion. However, gastroenterology specialty appears to be a better predictor of ADR than annual case volume.