Prospective, randomized study comparing two different regimens of split-dose polyethylene glycol and their effect on endoscopic outcomes

BACKGROUND

Different split regimens of polyethylene glycol are routinely used and no guidelines are available to select an optimal protocol of ingestion. This study aims to compare the efficacy and side effect profile of two different regimens of polyethylene glycol bowel preparation solution: PEG (3 + 1) vs. PEG (2 + 2).

METHODS

240 patients above the age of 18 years were included in the study between June 1st and November 31st, 2023. Patients were randomly assigned either to Group A, consisting of 115 patients receiving a 3 L of PEG the night before the colonoscopy, and 1 L the same morning of the procedure. Or to group B, where 125 patients ingested 2 L the night before the procedure, and the remaining 2 L the same morning. The cleansing efficacy was evaluated by the attending endoscopist using the Boston Bowel Preparation Scale, through a score assigned for each segment of the colon (0-3). Side effects, tolerability, and willingness to retake the same preparation were listed by an independent investigator using a questionnaire administered before the procedure.

RESULTS

A higher percentage of patients had gastric fullness with the 3 + 1 vs. 2 + 2 preparation (58.3% vs. 31.2%; p <.001). A higher Boston bowel preparation score was seen in patients who took the 2 + 2 vs. 3 + 1 preparation (7.87 vs. 7.23). Using the 2 + 2 preparation was significantly associated with higher Boston bowel preparation scores vs. the 3 + 1 preparation (OR = 1.37, p =.001, 95% CI 1.14, 1.64). After adjustment over other variables (age, gender, comorbidities, previous abdominal surgeries, presence of adenoma, and time between last dose and colonoscopy), results remained the same (aOR = 1.34, p =.003, 95% CI 1.10, 1.62).

CONCLUSION

While both (2 + 2) and (3 + 1) regimens of polyethylene glycol are a good choice for a successful colonoscopy, we recommend the use of (2 + 2) regimen for its superior efficacy in bowel cleansing.

Linked color imaging improves colorectal lesion detection especially for low performance endoscopists: An international trial in Asia

BACKGROUND AND AIM

Linked color imaging (LCI) is an image-enhanced endoscopy technique that accentuates the color difference between red and white, potentially improving the adenoma detection rate (ADR). However, it remains unclear whether LCI performance in detecting colorectal lesions differs based on endoscopists' experience levels. We aimed to evaluate the differences in LCI efficacy based on the experience levels of endoscopists by conducting an exploratory analysis.

METHODS

In this post hoc analysis of an international randomized controlled trial comparing the detection of adenoma and other lesions using colonoscopy with LCI and high-definition white light imaging (WLI), we included patients from 11 institutions across four countries/regions: Japan, Thailand, Taiwan, and Singapore. We retrospectively reviewed differences in the lesion detection of LCI according to endoscopists' colonoscopy history or ADR.

RESULTS

We included 1692 and 1138 patients who underwent colonoscopies performed by 54 experts (experience of ≥ 5000 colonoscopies) and by 43 non-experts (experience of < 5000 colonoscopies), respectively. Both expert and non-expert groups showed a significant improvement in ADR with LCI compared to WLI (expert, 61.7% vs 46.4%; P < 0.001; non-expert, 56.6% vs 46.4%; P < 0.001). LCI had no effect on sessile serrated lesion detection rate in non-experts (3.1% vs 2.5%; P = 0.518). LCI significantly improved detection rates in endoscopists with relatively low detection performance, defined as an ADR < 50%.

CONCLUSIONS

This exploratory study analyzed data from a previous trial and revealed that LCI is useful for both experts and non-experts and is even more beneficial for endoscopists with relatively low detection performance using WLI.

Single Versus Second Observer vs Artificial Intelligence to Increase the ADENOMA Detection Rate of Colonoscopy-A Network Analysis

BACKGROUND AND AIMS

Screening colonoscopy has significantly contributed to the reduction of the incidence of colorectal cancer (CRC) and its associated mortality, with adenoma detection rate (ADR) as the quality marker. To increase the ADR, various solutions have been proposed including the utilization of Artificial Intelligence (AI) and employing second observers during colonoscopies. In the interest of AI improving ADR independently, without a second observer, and the operational similarity between AI and second observer, this network meta-analysis aims at evaluating the effectiveness of AI, second observer, and a single observer in improving ADR.

METHODS

We searched the Medline, Embase, Cochrane, Web of Science Core Collection, Korean Citation Index, SciELO, Global Index Medicus, and Cochrane. A direct head-to-head comparator analysis and network meta-analysis were performed using the random-effects model. The odds ratio (OR) was calculated with a 95% confidence interval (CI) and p-value < 0.05 was considered statistically significant.

RESULTS

We analyzed 26 studies, involving 22,560 subjects. In the direct comparative analysis, AI demonstrated higher ADR (OR: 0.668, 95% CI 0.595-0.749, p < 0.001) than single observer. Dual observer demonstrated a higher ADR (OR: 0.771, 95% CI 0.688-0.865, p < 0.001) than single operator. In network meta-analysis, results were consistent on the network meta-analysis, maintaining consistency. No statistical difference was noted when comparing AI to second observer. (RR 1.1 (0.9-1.2, p = 0.3). Results were consistent when evaluating only RCTs. Net ranking provided higher score to AI followed by second observer followed by single observer.

CONCLUSION

Artificial Intelligence and second-observer colonoscopy showed superior success in Adenoma Detection Rate when compared to single-observer colonoscopy. Although not statistically significant, net ranking model favors the superiority of AI to the second observer.

Propofol sedation does not improve measures of colonoscopy quality but increase cost - findings from a large population-based cohort study

Background

Propofol is often used for sedation during colonoscopy. We assessed the impact of propofol sedation on colonoscopy related quality metrics and cost in a population-based cohort study.

Methods

All colonoscopies performed at 21 hospitals in the province of Ontario, Canada, during an 18-month period, from April 1, 2017 to October 31, 2018, using either propofol or conscious sedation were evaluated. The primary outcome was adenoma detection rate (ADR) and secondary outcomes were sessile serrated polyp detection rate (ssPDR), polyp detection rate (PDR), cecal intubation rate (CIR), and perforation rate. Binary outcomes were assessed using a modified Poisson regression model adjusted for clustering and potential confounders based on patient, procedure, and physician characteristics.

Findings

A total of 46,634 colonoscopies were performed, of which 16,408 (35.2%) received propofol and 30,226 (64.8%) received conscious sedation. Compared to conscious sedation, the use of propofol was associated with a lower ADR (24.6% vs. 27.0%, p < 0.0001) but not ssPDR (5.0% vs. 4.7%, p = 0.26), PDR (40.5% vs 40.4%, p = 0.79), CIR (97.1% vs. 96.8%, p = 0.15) or perforation rate (0.04% vs. 0.06%, p = 0.45). On multi-variable analysis, propofol sedation was not associated with any differences in ADR (RR = 0.90, 95% CI 0.74-1.10, p = 0.30), ssPDR (RR = 1.20, 95% CI 0.90-1.60, p = 0.22), PDR (RR = 1.00, 95% CI 0.90-1.11, p = 0.99), or CIR (RR = 1.00, 95% CI 0.80-1.26, p = 0.99). The additional cost associated with propofol sedation was $12,730,496 for every 100,000 cases.

Interpretation

The use of propofol sedation was not associated with improved colonoscopy related quality metrics but increased costs. The routine use of propofol for colonoscopy should be reevaluated.

Funding

None.

Human-artificial intelligence interaction in gastrointestinal endoscopy

The number and variety of applications of artificial intelligence (AI) in gastrointestinal (GI) endoscopy is growing rapidly. New technologies based on machine learning (ML) and convolutional neural networks (CNNs) are at various stages of development and deployment to assist patients and endoscopists in preparing for endoscopic procedures, in detection, diagnosis and classification of pathology during endoscopy and in confirmation of key performance indicators. Platforms based on ML and CNNs require regulatory approval as medical devices. Interactions between humans and the technologies we use are complex and are influenced by design, behavioural and psychological elements. Due to the substantial differences between AI and prior technologies, important differences may be expected in how we interact with advice from AI technologies. Human–AI interaction (HAII) may be optimised by developing AI algorithms to minimise false positives and designing platform interfaces to maximise usability. Human factors influencing HAII may include automation bias, alarm fatigue, algorithm aversion, learning effect and deskilling. Each of these areas merits further study in the specific setting of AI applications in GI endoscopy and professional societies should engage to ensure that sufficient emphasis is placed on human-centred design in development of new AI technologies.

Comparison of the characteristics of the CF-H290I and PCF-Q260JI colonoscopes in non-sedated patients with a history of abdominal or pelvic surgery: a randomized controlled study

BACKGROUND AND AIM

The purpose of this randomized controlled study was to compare the characteristics of the CF-H290I (high-definition) colonoscope with those of the PCF-Q260JI (high-resolution) colonoscope in non-sedated patients with a history of abdominal or pelvic surgery in an effort to help endoscopists to select more effectively and objectively between the various colonoscopes.

METHODS

A total of 397 patients who underwent colonoscopy at the Affiliated Wuxi People's Hospital of Nanjing Medical University, between August 2022 and October 2022 were randomized to a CF-H290I group (n = 198) or a PCF-Q260JI group (n = 199) using a computer-generated allocation method. We compared the adenoma detection rate (ADR), patient satisfaction with the examination, discomfort associated with colonoscopy including abdominal distension and pain, cecal intubation time, and patient willingness to undergo colonoscopy in the future between the CF-H290I and PCF-Q260JI groups.

RESULTS

There was no statistically significant difference in the overall ADR between the CF-H290I and PCF-Q260JI groups (81 [40.9%] vs 63 [31.7%], Z = 3.674, P = 0.055). However, the ADRs in the transverse colon and left colon were significantly higher in the CF-H290I group (22 [11.1%] vs 6 [3.0%], Z = 9.588, P = 0.002 and 57 [28.8%] vs 37 [18.6%], Z = 5.212, P = 0.017, respectively). More sessile serrated lesions were detected in the CF-H290I group (52 [26.3] vs 30 [15.1%], Z = 7.579, P = 0.006). Patient satisfaction with colonoscopy was better in the PCF-Q260JI group (8.91 ± 1.09 vs 8.51 ± 1.44, t = -3.158, P < 0.01) with less likelihood of discomfort (23 [11.6%] vs 41 [20.7%], Z = 6.144, P = 0.013), The number of patients willing to undergo colonoscopy in the future was significantly greater in the PCF-Q260JI group (168 [84.4%] vs 149 [75.3%], Z = 5.186, P = 0.023). The cecal intubation time was significantly shorter in the CF-H290I group (256.09 ± 155.70 s vs 315.64 ± 171.64 s, P = 0.004). There were no complications such as perforation or bleeding in either group.

CONCLUSION

The CF-H290I and PCF-Q260JI colonoscopes each have advantages when used in patients with a history of abdominal or pelvic surgery. The CF-H290I has higher ADRs in the transverse and left colon whereas the PCF-Q260JI is less painful and better accepted by patients. This study was approved by the Clinical Research Ethics Committee of Wuxi People's Hospital and was registered in the Chinese Clinical Trial Registry (ChiCTR2200063092).

Excellent Bowel Preparation Quality Is Not Superior to Good Bowel Preparation Quality for Improving Adenoma/Polyp Detection Rate

Background

Adequate bowel preparation quality is essential for high-quality colonoscopy according to the current guidelines. However, the excellent effect of bowel preparation on adenoma/polyp detection rate (ADR/PDR) remained controversial.

Methods

During the period from December 2020 to August 2022, a total of 1566 consecutive patients underwent colonoscopy by an endoscopist. Their medical records were reviewed. According to the Boston bowel preparation scale, patients were divided into excellent, good, and poor bowel preparation quality groups. ADR/PDR, diminutive ADR/PDR, small ADR/PDR, intermediate ADR/PDR, large ADR/PDR, and number of adenomas/polyps were compared among them. Logistic regression analyses were performed to identify the factors that were significantly associated with ADR/PDR.

Results

Overall, 1232 patients were included, of whom 463, 636, and 133 were assigned to the excellent, good, and poor groups, respectively. The good group had a significantly higher ADR/PDR (63% vs 55%, P = .015) and a larger number of adenomas/polyps (2.5 ± 3.2 vs 2.0 ± 2.8, P = .030) than the poor group. Both ADR/PDR (63% vs 55%, P = .097) and number of adenomas/polyps (2.2 ± 2.8 vs 2.0 ± 2.8, P = .219) were not significantly different between excellent and poor groups. The excellent (9% vs 4%, P = .045) and good (9% vs 4%, P = .040) groups had a significantly higher intermediate ADR/PDR than the poor group. Logistic regression analyses showed that either good (odds ratio [OR] = 1.786, 95% CI = 1.046-3.047, P = .034) or excellent (OR = 2.179, 95% CI = 1.241-3.826, P = .007) bowel preparation quality was independently associated with a higher ADR/PDR compared with poor bowel preparation quality. Excellent (OR = 1.202, 95% CI = 0.848-1.704, P = .302) bowel preparation quality was not independently associated with a higher ADR/PDR compared with good bowel preparation quality.

Conclusions

The pursuit of excellence in bowel preparation does not show an association with increased ADR/PDR and number of adenomas/polyps compared with a good level. In addition, our study further contributes to the existing evidence that poor bowel preparation compromises ADR/PDR and number of adenomas/polyps.

Evaluation of computer aided detection during colonoscopy among Veterans: Randomized clinical trial

BACKGROUND

There has been significant interest in use of computer aided detection (CADe) devices in colonoscopy to improve polyp detection and reduce miss rate.

AIM

To investigate the use of CADe amongst veterans.

METHODS

Between September 2020 and December 2021, we performed a randomized controlled trial to evaluate the impact of CADe. Patients at Veterans Affairs Palo Alto Health Care System presenting for screening or low-risk surveillance were randomized to colonoscopy performed with or without CADe. Primary outcomes of interest included adenoma detection rate (ADR), adenomas per colonoscopy (APC), and adenomas per extraction. In addition, we measured serrated polyps per colonoscopy, non-adenomatous, non-serrated polyps per colonoscopy, serrated polyp detection rate, and procedural time.

RESULTS

A total of 244 patients were enrolled (124 with CADe), with similar patient characteristics (age, sex, body mass index, indication) between the two groups. Use of CADe was found to have decreased number of adenomas (1.79 vs 2.53, P = 0.030) per colonoscopy compared to without CADe. There was no significant difference in number of serrated polyps or non-adenomatous non-serrated polyps per colonoscopy between the two groups. Overall, use of CADe was found to have lower ADR (68.5% vs 80.0%, P = 0.041) compared to without use of CADe. Serrated polyp detection rate was lower with CADe (3.2% vs 7.5%) compared to without CADe, but this was not statistically significant (P = 0.137). There was no significant difference in withdrawal and procedure times between the two groups or in detection of adenomas per extraction (71.4% vs 73.1%, P = 0.613). No adverse events were identified.

CONCLUSION

While several randomized controlled trials have demonstrated improved ADR and APC with use of CADe, in this RCT performed at a center with high ADR, use of CADe was found to have decreased APC and ADR. Further studies are needed to understand the true impact of CADe on performance quality among endoscopists as well as determine criteria for endoscopists to consider when choosing to adopt CADe in their practices.

Artificial intelligence fails to improve colonoscopy quality: A single centre retrospective cohort study

BACKGROUND

Limited data currently exists on the clinical utility of Artificial Intelligence Assisted Colonoscopy (AIAC) outside of clinical trials.

AIM

To evaluate the impact of AIAC on key markers of colonoscopy quality compared to conventional colonoscopy (CC).

METHODS

This single-centre retrospective observational cohort study included all patients undergoing colonoscopy at a secondary centre in Brisbane, Australia. CC outcomes between October 2021 and October 2022 were compared with AIAC outcomes after the introduction of the Olympus Endo-AID module from October 2022 to January 2023. Endoscopists who conducted over 50 procedures before and after AIAC introduction were included. Procedures for surveillance of inflammatory bowel disease were excluded. Patient demographics, proceduralist specialisation, indication for colonoscopy, and colonoscopy quality metrics were collected. Adenoma detection rate (ADR) and sessile serrated lesion detection rate (SSLDR) were calculated for both AIAC and CC.

RESULTS

The study included 746 AIAC procedures and 2162 CC procedures performed by seven endoscopists. Baseline patient demographics were similar, with median age of 60 years with a slight female predominance (52.1%). Procedure indications, bowel preparation quality, and caecal intubation rates were comparable between groups. AIAC had a slightly longer withdrawal time compared to CC, but the difference was not statistically significant. The introduction of AIAC did not significantly change ADR (52.1% for AIAC vs 52.6% for CC, P = 0.91) or SSLDR (17.4% for AIAC vs 18.1% for CC, P = 0.44).

CONCLUSION

The implementation of AIAC failed to improve key markers of colonoscopy quality, including ADR, SSLDR and withdrawal time. Further research is required to assess the utility and cost-efficiency of AIAC for high performing endoscopists.

Trend of the polyp and adenoma detection rate by sex and age in asymptomatic average-risk and high-risk individuals undergoing screening colonoscopy, 2012-2019

Adenoma detection rate (ADR) is an imperative quality measure for colorectal cancer (CRC) screening. This retrospective observational study aimed to determine the trend of polyp detection rate (PDR) and ADR in asymptomatic average- and high-risk participants in different age groups who underwent screening colonoscopy over the seven years from April 2012 to March 2019 in a tertiary gastroenterology referral center of Iran. Of 1676 participants, 51.8 % were men (mean age 52.3 years). The overall PDR and ADR were 22.7 %, and 13.5 %, respectively. Both Polyps and adenomas were more common in age groups 51-59 and ≥60 years in high-risk patients than in the corresponding groups of average-risk patients (p < 0.05). Also, both PDR and ADR were more frequent in men than in women among all studied age groups, but it was statistically significant only for the youngest age group (16.8 % versus 10.5 %, p < 0.05) for PDR and the oldest age group (19.7 % versus 13 %, p < 0.05) for ADR, respectively. The trend of total ADR was upward over 7 years in both average-risk (6.7 % to 13.3 %) and high-risk (9.8 % to 27 %) groups and across all age groups in both sexes. Multivariable logistic regression revealed that high-risk individuals had an elevated risk of adenoma compared with average-risk patients (OR: 1.6, p = 0.006). Substantial variation in thresholds of polyp and adenoma detection by age, sex, and risk categories emphasizes the need for a risk-adapted approach to CRC screening and prevention programs.

Texture and color enhancement imaging (TXI) plus endocuff vision versus TXI alone for colorectal adenoma detection: a randomized controlled trial

BACKGROUND AND AIMS

Increasing the adenoma detection rate (ADR) helps reduce the risk of post-colonoscopy colorectal cancer. Texture and Color Enhancement Imaging (TXI) improves ADR by enhancing the brightness and contrast of endoscopic images. Endocuff Vision (ECV) is a mucosal exposure device that helps flatten the colonic folds. The benefit of combining TXI with ECV has not been studied previously. Thus, we aimed to compare the ADR between using TXI combined with ECV and TXI alone.

METHODS

We conducted a prospective randomized controlled trial recruiting patients aged ≥ 40 years who underwent colonoscopy for colorectal cancer screening or gastrointestinal symptoms. The participants were randomized in a 1:1 ratio into the TXI with ECV (TXI + ECV) and the TXI groups. Experienced endoscopists with ≥ 40% ADR performed all colonoscopies. The primary outcome was ADR.

RESULTS

We had 189 and 192 patients in the TXI + ECV and TXI groups, respectively. The baseline characteristics of both groups were comparable. The ADR was significantly higher in the TXI + ECV group than in the TXI group (65.6% vs. 52.1%, P = 0.007). Adenoma per colonoscopy (APC) was significantly greater in the TXI + ECV group than in the TXI group (1.6 vs. 1.2, P = 0.021), prominently proximal (1.0 vs. 0.7, P = 0.031), non-pedunculated (1.4 vs. 1.1, P = 0.035), and diminutive (1.3 vs. 1, P = 0.045) adenomas. Serrated lesion detection rate, insertion time, and withdrawal time did not differ between the groups.

CONCLUSION

Adding ECV to TXI significantly improves ADR and APC compared to using TXI alone.

TRIAL REGISTRATION

Thai Clinical Trials Registry TCTR20220507004.

Effectiveness of switching endoscopists for repeat surveillance colonoscopy: a retrospective study

BACKGROUND

Surveillance colonoscopy decreases colorectal cancer mortality; however, lesions are occasionally missed. Although an appropriate surveillance interval is indicated, variations may occur in the methods used, such as scope manipulation or observation. Therefore, individual endoscopists may miss certain areas. This study aimed to verify the effectiveness of performing repeat colonoscopies with a different endoscopist from the initial procedure.

METHODS

We retrospectively reviewed a database of 8093 consecutive colonoscopies performed in the Omori Red Cross Hospital from January 1st 2018 to June 30th 2021. Data from repeat total colonoscopies performed within three months were collected to assess missed lesions. The patients were divided into two groups according to whether the two examinations were performed by different endoscopists (group D) or the same endoscopist (group S). The primary outcome in both groups was the missed lesion detection rate (MLDR).

RESULTS

Overall, 205 eligible patients were analyzed. In total, 102 and 103 patients were enrolled in groups D and S, respectively. The MLDR was significantly higher in group D (61.8% vs. 31.1%, P < 0.0001). Multivariate logistic regression analysis for the detection of missed lesions identified performance by the different endoscopists (odds ratio, 3.38; 95% CI, 1.81-6.30), and sufficient withdrawal time (> 6 min) (odds ratio, 3.10; 95% CI, 1.12-8.61) as significant variables.

CONCLUSIONS

Overall, our study showed a significant improvement in the detection of missed lesions when performed by different endoscopists. When performing repeat colonoscopy, it is desirable that a different endoscopist perform the second colonoscopy.

TRIAL REGISTRATION

This study was approved by the Institutional Review Board of the Omori Red Cross Hospital on November 28, 2022 (approval number:22-43).

The incremental yield of adenoma detection with I-Scan versus high-definition white light colonoscopy-a systematic review and meta-analysis of randomized studies

INTRODUCTION

The incremental yield of I-Scan virtual chromoendoscopy compared to high-definition white light endoscopy (HD-WLE) in detection of colorectal adenomas has not been thoroughly elucidated.

METHODS

A systematic search from inception to April 2023 was conducted to identify randomized controlled trials (RCTs) comparing I-Scan to HD-WLE for detection of adenomas. A random effects model was used to compute risk difference (RD) with corresponding 95% confidence intervals in adenoma detection rate (ADR). Influence analysis was done to assess robustness of findings. The number needed to diagnose was computed. Heterogeneity was assessed using the I2 statistic and explored further by subgroup analyses defined a priori. Certainty in effect estimates was assessed using the GRADE approach.

RESULTS

We identified four studies (I-Scan n = 730, HD-WLE n = 765). I-Scan increased adenoma detection by 9% (risk difference (RD), 0.09; 0.04, 0.14; I2 02%; certainty, low). Influence analysis revealed that the gain in yield remained statistically significant with exclusion of all but one study. The number needed to capture one additional adenomatous polyp with I-Scan use was 11.2. I-Scan 1 use was associated with a statistically significant gain in ADR, whereas no significant difference in ADR was noted with I-Scan use on subgroup analysis.

DISCUSSION

In conclusion, I-Scan increases the yield of adenoma detection by 9% compared to HD-WLE, with low certainty in the estimate of this effect. Data on the gain in yield of detecting large polyps, sessile serrated lesions, and on the impact of formally training endoscopists and trainees in I-Scan use and similar technology on adenoma detection rate are needed.

Human immunodeficiency virus patients with low CD4 counts are more likely to have precancerous polyps identified during index colonoscopy

BACKGROUND

Antiretroviral treatment (ART) has improved the life expectancy of patients living with human immunodeficiency virus (HIV). As these patients age, they are at increased risk for developing non-acquired immunodeficiency syndrome defining malignancies (NADMs) such as colon cancers.

AIM

To determine which factors are associated with the development of precancerous polyps on screening colonoscopy in patients with HIV and to investigate whether HIV disease status, measured by viral load and CD4 count, might influence precancerous polyp development.

METHODS

A retrospective review of records at two urban academic medical centers was performed for HIV patients who had a screening colonoscopy between 2005-2015. Patients with a history of colorectal cancer or polyps, poor bowel preparation, or inflammatory bowel disease were excluded. Demographic data such as sex, age, race, and body mass index (BMI) as well as information regarding the HIV disease status such as CD4 count, viral load, and medication regimen were collected. Well-controlled patients were defined as those that had viral load < 50 copies, and poorly-controlled patients were those with viral load ≥ 50. Patients were also stratified based on their CD4 count, comparing those with a low CD4 count to those with a high CD4 count. Using colonoscopy reports in the medical record, the size, histology, and number of polyps were recorded for each patient. Precancerous polyps included adenomas and proximal serrated polyps. Data was analyzed using Fisher's exact tests and logistic regression through SAS 3.8 software.

RESULTS

Two hundred and seven patients met our inclusion criteria. The mean age was 56.13 years, and 58% were males. There were no significant differences in terms of age, race or ethnicity, insurance, and smoking status between patients with CD4 counts above or below 500. BMI was lower in patients with CD4 count < 500 as compared to those with count > 500 (P = 0.0276). In patients with CD4 > 500, 53.85% of patients were female, and 70.87% of patients with CD4 < 500 were male (P = 0.0004). Only 1.92% of patients with CD4 ≥ 500 had precancerous polyps vs 10.68% of patients with CD4 < 500 (P = 0.0102). When controlled for sex, BMI, and ART use, patients with CD4 < 500 were 9.01 times more likely to have precancerous polyps [95% confidence interval (CI): 1.69-47.97; P = 0.0100]. Patients taking non-nucleoside reverse transcriptase inhibitors were also found to be 10.23 times more likely to have precancerous polyps (95%CI: 1.08-97.15; P = 0.0428). There was not a significant difference noted in precancerous polyps between those that had viral loads greater or less than 50 copies.

CONCLUSION

Patients with low CD4 counts were more likely to have precancerous polyps on their screening colonoscopy although the etiology for this association is unclear. We also found an increased risk of precancerous polyps in patients taking non-nucleoside reverse transcriptase inhibitors, which is contradictory to prior literature showing ART has decreased the risk of development of NADMs. However, there have not been studies looking at colorectal cancer and ART by drug class, to our knowledge. Further prospective studies are needed to determine the effect of HIV control and therapies on polyp development.

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

INTRODUCTION

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

AREAS COVERED

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

EXPERT OPINION

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

Efficacy of image-enhanced endoscopy for colorectal adenoma detection: A multicenter, randomized trial

BACKGROUND

Improved adenoma detection at colonoscopy has decreased the risk of developing colorectal cancer. However, whether image-enhanced endoscopy (IEE) further improves the adenoma detection rate (ADR) is controversial.

AIM

To compare IEE with white-light imaging (WLI) endoscopy for the detection and identification of colorectal adenoma.

METHODS

This was a multicenter, randomized, controlled trial. Participants were enrolled between September 2019 to April 2021 from 4 hospital in China. Patients were randomly assigned to an IEE group with WLI on entry and IEE on withdrawal (n = 2113) or a WLI group with WLI on both entry and withdrawal (n = 2098). The primary outcome was the ADR. The secondary endpoints were the polyp detection rate (PDR), adenomas per colonoscopy, adenomas per positive colonoscopy, and factors related to adenoma detection.

RESULTS

A total of 4211 patients (966 adenomas) were included in the analysis (mean age, 56.7 years, 47.1% male). There were 2113 patients (508 adenomas) in the IEE group and 2098 patients (458 adenomas) in the WLI group. The ADR in two group were not significantly different [24.0% vs 21.8%, 1.10, 95% confidence interval (CI): 0.99-1.23, P = 0.09]. The PDR was higher with IEE group (41.7%) than with WLI group (36.1%, 1.16, 95%CI: 1.07-1.25, P = 0.01). Differences in mean withdrawal time (7.90 ± 3.42 min vs 7.85 ± 3.47 min, P = 0.30) and adenomas per colonoscopy (0.33 ± 0.68 vs 0.28 ± 0.62, P = 0.06) were not significant. Subgroup analysis found that with narrow-band imaging (NBI), between-group differences in the ADR, were not significant (23.7% vs 21.8%, 1.09, 95%CI: 0.97-1.22, P = 0.15), but were greater with linked color imaging (30.9% vs 21.8%, 1.42, 95%CI: 1.04-1.93, P = 0.04). the second-generation NBI (2G-NBI) had an advantage of ADR than both WLI and the first-generation NBI (27.0% vs 21.8%, P = 0.01; 27.0% vs 21.2.0%, P = 0.01).

CONCLUSION

This prospective study confirmed that, among Chinese, IEE didn’t increase the ADR compared with WLI, but 2G-NBI increase the ADR.

Is There a Difference in Adenoma Detection Rates According to Indication? An Experience in a Panamanian Colorectal Cancer Screening Program

Background

The benefit of colorectal cancer screening in reducing cancer risk and related death is unclear. There are quality measure indicators and multiple factors that affect the performance of a successful colonoscopy. The main objective of our study was to identify if there is a difference in polyp detection rate (PDR) and adenoma detection rate (ADR) according to colonoscopy indication and which factors might be associated.

Methods

We conducted a retrospective review of all colonoscopies performed between January 2018 and January 2019, in a tertiary endoscopic center. All patients ≥ 50 years old scheduled for a nonurgent colonoscopy and screening colonoscopy were included. We stratified the total number of colonoscopies into two categories according to the indication: screening vs. non-screening, and then calculated PDR, ADR and serrated polyp detection rate (SDR). We also performed logistic regression model to identify factors associated with detecting polyps and adenomatous polyps.

Results

A total of 1,129 and 365 colonoscopies were performed in the non-screening and screening group, respectively. In comparison with the screening group, PDR and ADR were lower for the non-screening group (33% vs. 25%; P = 0.005 and 17% vs. 13%; P = 0.005). SDR was non-significantly lower in the non-screening group when compared with the screening group (11% vs. 9%; P = 0.53 and 22% vs. 13%; P = 0.007).

Conclusion

In conclusion, this observational study reported differences in PDR and ADR depending on screening and non-screening indication. These differences could be related to factors related to the endoscopist, time slot allotted for colonoscopy, population background, and external factors.

Factors affecting the quality of bowel preparation for colonoscopy in hard-to-prepare patients: Evidence from the literature

Adequate bowel cleansing is critical for a high-quality colonoscopy because it affects diagnostic accuracy and adenoma detection. Nevertheless, almost a quarter of procedures are still carried out with suboptimal preparation, resulting in longer procedure times, higher risk of complications, and higher likelihood of missing lesions. Current guidelines recommend high-volume or low-volume polyethylene glycol (PEG)/non-PEG-based split-dose regimens. In patients who have had insufficient bowel cleansing, the colonoscopy should be repeated the same day or the next day with additional bowel cleansing as a salvage option. A strategy that includes a prolonged low-fiber diet, a split preparation regimen, and a colonoscopy within 5 h of the end of preparation may increase cleansing success rates in the elderly. Furthermore, even though no specific product is specifically recommended in the other cases for difficult-to-prepare patients, clinical evidence suggests that 1-L PEG plus ascorbic acid preparation are associated with higher cleansing success in hospitalized and inflammatory bowel disease patients. Patients with severe renal insufficiency (creatinine clearance < 30 mL/min) should be prepared with isotonic high volume PEG solutions. Few data on cirrhotic patients are currently available, and no trials have been conducted in this population. An accurate characterization of procedural and patient variables may lead to a more personalized approach to bowel preparation, especially in patients undergoing resection of left colon lesions, where intestinal preparation has a poor outcome. The purpose of this review was to summarize the evidence on the risk factors influencing the quality of bowel cleansing in difficult-to-prepare patients, as well as strategies to improve colonoscopy preparation in these patients.

Melanosis coli: a contrast effect or an oncogenic effect? A large-scale retrospective cohort study

BACKGROUND

Melanosis coli is characterized by brown mucosa with pigmentation. Studies have showed an increased adenoma detection rate in melanosis patients, whether it is caused by a contrast effect or an oncogenic effect is still controversial. The detection of serrated polys in melanosis patients remains unknown.

AIMS

The study aimed to clarify the correlation of adenoma detection rate with melanosis coli and discuss outcomes in less-experienced endoscopists. Serrated polyp detection rate was also been investigated.

METHODS

A total of 2150 patients and 39,630 controls were enrolled. A propensity score matching method was used to balance covariates between the two groups. The detection of polyps, adenomas, serrated polyps, and their features was analyzed.

RESULTS

The polyp detection rate (44.65% vs 41.01%, P = 0.005) and adenoma detection rate (30.34% vs 23.92%, P < 0.001) were significantly higher, and the serrated polyp detection rate (0.93% vs 1.58%, P = 0.033) was significantly lower in melanosis coli. The percentage of low-risk adenomas (44.60% vs 39.16%, P < 0.001) and polyps with 6 to 10 mm in size (20.16% vs 16.21%, P < 0.001) were higher in melanosis coli. The detection of large serrated polyps was lower (0.11% vs 0.41%, P = 0.026) in melanosis coli.

CONCLUSION

Melanosis coli correlates with an increased adenoma detection rate. The detection of large serrated polyps was lower in melanosis patients. Melanosis coli may not be considered a precancerous lesion.

The application of artificial intelligence in improving colonoscopic adenoma detection rate: Where are we and where are we going

Colorectal cancer (CRC) is one of the common malignant tumors in the world. Colonoscopy is the crucial examination technique in CRC screening programs for the early detection of precursor lesions, and treatment of early colorectal cancer, which can reduce the morbidity and mortality of CRC significantly. However, pooled polyp miss rates during colonoscopic examination are as high as 22%. Artificial intelligence (AI) provides a promising way to improve the colonoscopic adenoma detection rate (ADR). It might assist endoscopists in avoiding missing polyps and offer an accurate optical diagnosis of suspected lesions. Herein, we described some of the milestone studies in using AI for colonoscopy, and the future application directions of AI in improving colonoscopic ADR.

Clinical Evaluation of Computer-Aided Colorectal Neoplasia Detection Using a Novel Endoscopic Artificial Intelligence: A Single-Center Randomized Controlled Trial

INTRODUCTION

Computer-aided diagnostic systems are emerging in the field of gastrointestinal endoscopy. In this study, we assessed the clinical performance of the computer-aided detection (CADe) of colonic adenomas using a new endoscopic artificial intelligence system.

METHODS

This was a single-center prospective randomized study including 415 participants allocated into the CADe group (n = 207) and control group (n = 208). All endoscopic examinations were performed by experienced endoscopists. The performance of the CADe was assessed based on the adenoma detection rate (ADR). Additionally, we compared the adenoma miss rate for the rectosigmoid colon (AMRrs) between the groups.

RESULTS

The basic demographic and procedural characteristics of the CADe and control groups were as follows: mean age, 54.9 and 55.9 years; male sex, 73.9% and 69.7% of participants; and mean withdrawal time, 411.8 and 399.0 s, respectively. The ADR was 59.4% in the CADe group and 47.6% in the control group (p = 0.018). The AMRrs was 11.9% in the CADe group and 26.0% in the control group (p = 0.037).

CONCLUSION

The colonoscopy with the CADe system yielded an 11.8% higher ADR than that performed by experienced endoscopists alone. Moreover, there was no need to extend the examination time or request the assistance of additional medical staff to achieve this improved effectiveness. We believe that the novel CADe system can lead to considerable advances in colorectal cancer diagnosis.

Escrutinio para el cáncer de colon: ¿cuál fue el impacto en los primeros 2 años de la pandemia de COVID-19? Experiencia en una clínica privada ambulatoria

BACKGROUND

COVID-19 pandemic had a negative impact on colorectal cancer (CRC) screening programs.

OBJECTIVE

The care strategy was modified throughout the pandemic, this paper evaluates its impact and short-term consequences.

METHODS

A retrospective, descriptive and cross-sectional study was carried out in a private ambulatory endoscopic center, in average risk subjects. The study compared two periods: pre-pandemic and pandemic (subdivided into pre-vaccination and vaccination).

RESULTS

During this period, 54.4% of scheduled colonoscopies were due to the screening program. The average age was 60.4 ± 7 years. Women were 52.0%. The overall cancellation rate was 41.1%, higher during pre-vaccination period. There were no differences in the degree of colonic cleansing, colonoscope exit time, and patient satisfaction. The adenoma detection rate (38.4% vs. 42.8% vs. 36.4%; p = 0.8) and the total number of adenomas (p = 0.02) was statistically significant during the pre-vaccination period. The rate of adenoma/patient showed a higher trend during this period (p = 0.06). The number of colorectal cancers was 10, without differences between periods.

CONCLUSION

In conclusion, the impact of the decrease in screening colonoscopy procedures for CRC detection was similar to what was seen worldwide. In this period no increase in cancer cases, although this effect may be observed in the long term.

An Italian prospective multicenter study on colonoscopy practice and quality: What has changed in the last 10 years

BACKGROUND

A relevant number of adenomas can be missed during colonoscopy.

AIMS

Assess the current status of colonoscopy procedures in Italian centers.

METHODS

A prospective observational study involving 17 hospitals (34 endoscopists) included consecutive patients undergoing standard colonoscopy. In the first phase, endoscopists performed consecutive colonoscopies. In the second phase, retraining via an online learning platform was planned, while in the third phase data were collected analogously to phase 1.

RESULTS

A total of 3,504 patients were enrolled. Overall, a BBPS score ≥6 was obtained in 95.6% of cases (94.8% and 96.9% in the pre- and post-training phases, respectively). 88.4% of colonoscopies had a withdrawal time ≥6 min (88.2% and 88.7% in the pre- and post-training phases). Median adenoma detection rate (ADR) was 39.1%, with no significant differences between the pre- and post-training phases (40.1% vs 36.9%; P = 0.83). In total, 81% of endoscopists had a ADR performance above the 25% threshold.

CONCLUSION

High colonoscopy quality standards are achieved by the Italian hospitals involved. Quality improvement initiatives and repeated module-based colonoscopy-training have been promoted in Italy during the last decade, which appear to have had a significant impact on quality colonoscopy metrics together with the activation of colorectal cancer screening programs.

Quality of colonoscopy performed by medical or surgical specialists and trainees in five Australian hospitals

BACKGROUND

Ensuring colonoscopy procedure quality is vital to the success of screening and surveillance programmes for bowel cancer in Australia. However, the data on the performance of quality metrics, through adequate adenoma detection, bowel preparation, and procedure completion rates, in the Australian public sector is limited. Understanding these can inform quality improvement to further strengthen our capacity for prevention and early detection of colorectal cancer.

AIM

To determine the quality of colonoscopy in Australian teaching hospitals and their association with proceduralist specialty, trainee involvement, and location.

METHODS

We retrospectively evaluated 2443 consecutive colonoscopy procedure reports from 1 January to 1 April, 2018 from five public teaching tertiary hospitals in Australia (median 60 years old, 49% male). Data for bowel preparation quality, procedure completion rates, and detection rates of clinically significant adenomas, conventional adenomas, and serrated lesions was collected and compared to national criteria for quality in colonoscopy. Participating hospital, proceduralist specialty, and trainee involvement indicators were used for stratification. Data was analysed using Chi-squared tests of independence, Mann-Whitney U, One-way ANOVA, and multivariate binary logistic regression.

RESULTS

Fifty-two point two percent (n = 1276) and 43.3% (n = 1057) were performed by medical and surgical proceduralists respectively, whilst 29.8% (n = 728) involved a trainee. Inadequate bowel preparation affected 7.3% of all procedures. The procedure completion rate was 95.1%, which increased to 97.5% after adjustment for bowel preparation quality. The pooled cancer, adenoma, and serrated lesion detection rates for all five hospitals were 3.5%, 40%, and 5.9% respectively. Assessed hospitals varied significantly by patient age (P < 0.001), work-force composition (P < 0.001), adequacy of bowel preparation (P < 0.001), and adenoma detection rate (P < 0.001). Two hospitals (40%) did not meet all national criteria for quality, due to a procedure completion rate of 94.5% or serrated lesion detection rate of 2.6%. Although lower than the other hospitals, the difference was not significant. Compared with surgical specialists, procedures performed by medical specialists involved older patients [65 years (inter-quartile range, IQR 58-73) vs 64 years (IQR 56-71); P = 0.04] and were associated with a higher adenoma detection rate [odds ratio (OR) 1.53; confidence interval: 1.21-1.94; P < 0.001]. Procedures involving trainee proceduralists were not associated with differences in the detection of cancer, adenoma, or serrated lesions, compared with specialists, or according to their medical or surgical background. On multivariate analysis, cancer detection was positively associated with patient age (OR 1.04; P < 0.001) and negatively associated with medical compared to surgical proceduralists (OR 0.54; P = 0.04). Conventional adenoma detection rates were independently associated with increasing patient age (OR 1.04; P < 0.001), positively associated with medical compared to surgical proceduralists (OR 1.41; P = 0.002) and negatively associated with male gender (OR 0.53; P < 0.001).

CONCLUSION

Significant differences in the quality of colonoscopy in Australia exist, even when national benchmarks are achieved. The role of possible contributing factors, like procedural specialty and patient gender need further evaluation.

Impact of sedation type on adenoma detection rate by colonoscopy

BACKGROUND & AIMS

Endoscopic detection of polyps and adenomas decreases the incidence and mortality of colorectal cancer. The available data concerning the relationship between the sedation type and adenoma detection rate (ADR) or polyp detection rate (PDR) is inconclusive. The aim of our study was to evaluate the impact of conscious vs. deep (propofol) sedation on the ADR/PDR in diagnostic and screening colonoscopies.

METHODS

This was a retrospective cohort study. Patients aged 50-75 years old presenting for a first screening or diagnostic colonoscopy were included. Baseline demographic characteristics were collected, as well as PDR and ADR. Endoscopic withdrawal time and quality of bowel preparation rated in a binary fashion were also collected. Two multivariate logistic regression models were used to evaluate the independent predictors of endoscopic detection of polyps and adenomas.

RESULTS

574 patients met our inclusion criteria. Mean age was 59.26 ± 7.21 with 52.4% females and an average BMI of 28.08 ± 4.89. 374 patients (65.2%) underwent screening colonoscopies, and deep sedation was performed in 200 patients (34.8%). Only 4.7% had bad bowel preparation. PDR was 70% and ADR was 52%. On bivariate analysis, no significant difference was shown in PDR and ADR between conscious and deep sedation groups (0.70, 0.71; p = 0.712 and 0.50, 0.54; p = 0.394, respectively). On multivariate analysis for PDR, age and withdrawal time were independent predictors. For ADR, age, female sex, and withdrawal time were independent predictors. Sedation type and the indication did not reach statistical significance in both models.

CONCLUSION

The use of deep sedation didn't influence the ADR/PDR quality metrics in our mixed cohort of screening and diagnostic colonoscopies.

Prevalence of Adenomas on Surveillance Colonoscopies for Patients with a History of Colonic Polyps of Unknown Histology

BACKGROUND

Guidelines for surveillance colonoscopy depend on polyp histology. When patients present to a new healthcare system and report a personal history of "colon polyps," however, information on polyp histology is frequently unavailable.

AIMS

To assess adenoma prevalence in patients with a history of colonic polyps of unknown histology and to compare it to patients undergoing either screening colonoscopy or surveillance colonoscopy for known adenomatous polyps.

METHODS

This cohort study evaluated colonoscopies of patients ≥ 50 years of age over a 14-year period at a single institution. The exposure of interest was colonoscopy indication, categorized into three groups: screening colonoscopy, surveillance colonoscopy for history of colonic polyp(s) of unknown histology, and surveillance colonoscopy for history of adenoma(s). The primary outcome was adenoma detection rate. Multivariable logistic regression was used to assess the association between colonoscopy indication and adenoma detection rate.

RESULTS

Of 31,856 colonoscopies, the adenoma prevalence was 26.1% for patients undergoing screening colonoscopy, 32.9% for patients with a history of polyps of unknown histology, and 41.9% for patients with a history of known adenomatous polyps. Relative to screening colonoscopies, there were higher odds of adenoma detection in surveillance colonoscopies for polyps of unknown histology (aOR compared to screening 1.42, 95% CI 1.30-1.55) and even higher odds among surveillance colonoscopies for a history of adenoma (aOR compared to screening 1.89, 95% CI 1.75-2.05).

CONCLUSION

The adenoma prevalence on surveillance colonoscopy for patients with polyps of unknown histology was higher than that of screening colonoscopies but lower than that of surveillance colonoscopies for patients with adenomatous polyps.

Single-Day Low-Residue Diet Prior to Colonoscopy Demonstrates Improved Bowel Preparation Quality and Patient Tolerance over Clear Liquid Diet: A Randomized, Single-Blinded, Dual-Center Trial

BACKGROUND AND AIMS

Patients often refer to bowel preparation and associated dietary restrictions as the greatest deterrents to having a colonoscopy completed or performed. Large studies comparing a low-residue diet (LRD) and a clear liquid diet (CLD) are still limited. The aim of this study is to compare LRD and CLD with regard to bowel preparation quality, tolerance, and satisfaction among a diverse patient population.

METHODS

This study is a dual-center, randomized, single-blinded, prospective trial involving adult patients undergoing outpatient colonoscopy at the University of California Irvine Medical Center and an affiliated Veterans Administration hospital. Patients were randomized to consume either a CLD or a planned LRD for the full day prior to colonoscopy. Both groups consumed 4L split-dosed PEG-ELS. The adequacy of bowel preparation was evaluated using the Boston Bowel Preparation Score (BBPS). Adequate preparation was defined as a BBPS ≥ 6 with no individual segment less than a score of 2. Hunger and fatigue pre - and post-procedure were graded on a ten-point scale. Nausea, vomiting, bloating, abdominal cramping, overall discomfort, satisfaction with the diet, willingness to repeat the same preparation and overall experience were assessed.

RESULTS

A total of 195 subjects who underwent colonoscopy from October 2014 to October 2017 were included. The mean BBPS for the LRD and CLD groups was 8.38 and 7.93, respectively (p = 0.1). There was a significantly higher number of adequate preparations in the LRD group compared to CLD (p = 0.05). Evening hunger scores just before starting the bowel preparation were significantly lower in the LRD than the CLD group, 2.81 versus 5.97, respectively (p = 0.006). Subjects in the LRD group showed significantly less nausea (p = 0.047) and bloating (p = 0.04). Symptom scores for vomiting, abdominal cramping, and overall discomfort were similar between the groups. Satisfaction with diet was significantly higher in the LRD group than CLD, 72% versus 37.66%, respectively (p < 0.001). The overall colonoscopy experience and the satisfaction with the preparation itself were also better reported in the LRD group (p < 0.001 and p = 0.002, respectively).

CONCLUSIONS

This study, which included a diverse group of patients, demonstrated that patients using a LRD before colonoscopy achieve a bowel preparation quality that is superior to patients on a CLD restriction. This study shows that a low-residue diet improves patient satisfaction and results in significantly better tolerability of bowel preparation. As a less restrictive dietary regimen, the low-residue diet may help improve patient participation in colorectal cancer screening programs.

Factors affecting colorectal adenoma detection rate

Colorectal cancer is a kind of malignant tumors that seriously threatens the health of Chinese people, and its morbidity and mortality rank third and fifth among malignant tumors in China, respectively. High-quality colonoscopy is an effective means of preventing colorectal cancer. Adenoma detection rate (ADR) is defined as the proportion of those who have adenomas in the total number of patients undergoing colonoscopy. With the increase of ADR, the incidence rate and mortality rate of colorectal cancer gradually decrease. Previous studies have found that ADR is affected by many factors. In this paper, we describe the factors that affect ADR from the aspects of colonoscopy, doctors, and equipment, with a purpose to strengthen the understanding of endoscopists on ADR and to increase ADR during colonoscopy.

Water immersion sigmoidoscopy versus standard insufflation for colorectal cancer screening: A cohort study

BACKGROUND

Although the efficacy of water-assisted colonoscopy is well established, the role of water immersion sigmoidoscopy (WIS) remains unclear. We compared WIS with carbon dioxide insufflation sigmoidoscopy (CO₂S) on patient outcomes.

METHODS

We conducted an analysis of prospectively collected data from a single-center quality improvement program about patients undergoing unsedated screening sigmoidoscopy (WIS and CO₂S) between May 2019 and January 2020. Outcomes studied included the following: Rates of severe pain <17% (score of ≥7 on a numeric rating scale of 0-10, and on a Likert scale), willingness to repeat the procedure without sedation, adequate bowel cleanliness >75% (proportion of Boston Bowel Preparation Scale score: 2-3) and adenoma detection rate (ADR).

RESULTS

In total, 234 patients (111 WIS; 123 CO₂S) were included. All patients were aged 58 years and 58.9% were female; baseline characteristics were comparable between groups. There were no significant differences in rates of severe pain (WIS: 16.5%, CO₂S: 13.8%; P = 0.586), willingness to repeat the unsedated procedure (WIS: 82.3%, CO₂S: 84.5%; P = 0.713), adequate bowel cleanliness (WIS: 78.4%, CO₂S: 78%, P = 0.999) or ADR (WIS: 25.2%, CO₂S: 16.3%; P = 0.106) between groups. However, average procedure times were longer with WIS (9.06 min) compared to CO₂S (6.45 min; P < 0.001). Overall, 29.6% of women reported that they would repeat sigmoidoscopy only if sedated.

CONCLUSIONS

WIS does not ameliorate tolerance to and quality of sigmoidoscopy screening measured by several scores. When offered a choice, the women's willingness to repeat WIS or CO₂S without sedation was poor and raises concern on the opportunity of screening sigmoidoscopy without sedation in these subjects.

Adenoma and serrated lesion detection with distal attachment in screening colonoscopy: a randomized controlled trial

BACKGROUND

Adenoma detection rate (ADR) is the single most important measure of quality in colonoscopy, but little is known about the detection rate of serrated lesions (SLDR). To improve ADR, Endocuff Vision (EV) can be used. Studies have shown differing results as to the effect on ADR; an effect on SLDR has not been shown. To investigate the effect of Endocuff Vision on ADR in a screening population, this randomized controlled open label trial with concealed allocation was performed. Randomization to trial group was carried out by the endoscopist using prepared numbered envelopes.

METHODS

Patients referred as part of the national bowel screening program at Regional Hospital Herning, Denmark were recruited and allocated to one of two groups: Endocuff Vision colonoscopy (EVC) and standard colonoscopy (SC). Outcomes were ADR, mean number, site, and size of lesions per procedure. SLDR as outcome was added after inclusion had begun.

RESULTS

A total of 1178 participants were included, with 1166 (EVC 583 and SC 583) available for analysis. There was no clinical relevant difference in ADR (59.2% [CI 55.1; 63.1] v 60.5% [CI 56.5; 64.4]) or SLDR (13.0% [CI 10.5; 16.0] v 10.3% [CI 8.0; 13.0]) between groups. More serrated lesions were found per procedure (MSP) (0.2 v 0.1, IRR 57% [CI 17; 109]. Removal rate of EV was similar in the two study groups.

CONCLUSION

We found no significant effects of the use of Endocuff Vision on ADR, when compared to standard colonoscopy, but more serrated lesions were detected in the Endocuff group.

TRIAL REGISTRATION

Clinical Trials NCT04651062.

Impact of Fellow Participation During Colonoscopy on Adenoma Detection Rates

BACKGROUND

An endoscopist's adenoma detection rate (ADR) is inversely related to interval colorectal cancer risk and cancer mortality. Previous studies evaluating the impact of gastroenterology fellow participation in colonoscopy on ADR have generated conflicting results.

AIMS

We aimed to determine the impact of fellow participation, duration of fellowship training, and physician sex on ADR and advanced ADR (AADR).

METHODS

We retrospectively analyzed average-risk patients undergoing screening colonoscopy at Veterans Affairs New York Harbor Healthcare System Brooklyn Campus and Kings County Hospital Center. Review of colonoscopy and pathology reports were performed to obtain adenoma-specific details, including the presence of advanced adenoma and adenoma location (right vs. left colon).

RESULTS

There were 893 colonoscopies performed by attending only and 502 performed with fellow participation. Fellow participation improved overall ADR (44.6% vs. 35.4%, p < 0.001), right-sided ADR (34.1% vs. 25.2%, p < 0.001), and AADR (15.3% vs. 8.3%, p < 0.001); however, these findings were institution-specific. Year of fellowship training did not impact overall ADR or overall AADR, but did significantly improve right-sided AADR (p-value for trend 0.03). Female attending physicians were associated with increased ADR (47.1% vs. 37.0%, p = 0.0037). Fellow sex did not impact ADR.

CONCLUSIONS

Fellow participation in colonoscopy improved overall ADR and AADR, and female attending physicians were associated with improved ADR. Year of fellowship training did not impact overall ADR or AADR.

When should we perform colonoscopy to increase the adenoma detection rate?

The rate of adenoma detection is the most reliable quality indicator of colonoscopy. Studies have reported that colonoscopy performed in morning has a higher adenoma detection rate (ADR) than that performed in the afternoon. These studies have explained that several physician-related factors such as undergoing an emergency procedure the night before colonoscopy, accumulated workload, and increased fatigue level in the afternoon might have led to such finding. However, several opposing articles have indicated that the time of day and ADR is not quite related. Complex confounding factors can impact study results. Colonoscopy withdrawal time and bowel preparation quality are key factors. However, queue list numbers, participation of academic fellows, nurses' assistance, and the number of colonoscopies allocated per hour are also notable factors. Recently, an attempt has been made to homogenize the ADR in the morning and afternoon through artificial intelligence-assisted colonoscopy. This review article introduces the history of this long-debated topic, discusses points to consider in real-world practice, and suggests new ideas for planning future research. By understanding this issue, the rate of adenoma detection during colonoscopy is expected to be improved further.

Does time of day matter for colonoscopy quality? A review of over 13,000 screening colonoscopies in a colorectal surgery unit

BACKGROUND

There exists conflicting data in the literature with regard to adequate adenoma detection rate (ADR) as well as other quality metrics during colonoscopy based on the time of day that the procedure is performed. The aim of this study was to investigate the effect of time of day on quality metrics in patients undergoing screening colonoscopy.

METHODS

Screening colonoscopies performed between January 2010 and September 2018 by twenty-eight colorectal surgeons were queried from a prospectively maintained database. Quality parameters examined included adenoma detection rate (ADR), gender-specific ADR, withdrawal time, total examination time, cecal intubation rate, bowel preparation quality, and intra-procedural complications. Colonoscopies were compared between morning (07:30-11:59 AM) and afternoon (12:00-17:00 PM) groups.

RESULTS

There were 13,809 endoscopic screening examinations performed in asymptomatic patients older than 45 years. Patients had a mean age of 59.8 years, and 48.5% were female. A total of 8868 (64%) of the scopes were performed in the morning and 4941 (36%) were performed in the afternoon. Median endoscopist volume was 189 [54, 701] and included only surgeons who performed both afternoon and morning colonoscopies. There was no difference in both ADR and bowel preparation quality between the two groups. Both groups exceeded all national quality benchmarks, with the morning group having significantly shorter examination times.

CONCLUSIONS

In our practice, colonoscopies meet and exceed all national quality benchmarks, independent of the time of day they are performed.

Progress in understanding of factors related to colonoscopic adenoma detection rate

Adenoma detection rate (ADR) is the proportion of average-risk patients undergoing screening colonoscopy in whom an adenoma is found, and it is an important quality indicator of colonoscopy. ADR is closely related to the risk of interval colorectal cancer. A deeply study of ADR is essential for endoscopists. In this paper, we review the progress in the understanding of factors related to ADR before, during, and after colonoscopy, as well as several issues worthy of attention.

Application of deep learning based artificial intelligence technology in identification of colorectal polyps

Colorectal cancer is a cancer type that is most suitable for screening since subjects at risk of this malignancy can clearly benefit from colonoscopy screening. In 2017, there were about 431951 new cases of colorectal cancer in China, with an increase of 203.5% in 28 years. Early detection and early removal of adenomatous polyps and other precancerous lesions during colonoscopy can prevent the occurrence of colorectal cancer. However, various factors lead to missed diagnosis of polyps during colonoscopy, which increases the risk of colorectal cancer. In recent years, with the rapid development of artificial intelligence technology in the medical field, colonoscopy assisted by artificial intelligence can increase the detection rate of polyps and improve the quality of colonoscopy. This paper mainly reviews the quality control, bowel preparation, diagnosis and classification of colorectal polyps, and the future opportunities and challenges faced by convolutional neural network based artificial intelligence technology in the field of colonoscopy, hoping to provide some reference for clinical work.

Comparing right colon adenoma detection rate during water exchange and air insufflation: a double-blind randomized controlled trial

BACKGROUND

Randomized controlled trials (RCTs) have reported that water exchange (WE) produced the highest adenoma detection rate (ADR) but did not evaluate right colon adenoma detection rate (rADR) as a primary outcome and only one of the trials employed blinded colonoscopists. The aim of our study was to determine whether, compared with air insufflation, WE significantly increases rADR and right colon serrated lesion detection rate (rSLDR) and decreases adenoma miss rate (rAMR).

METHODS

This prospective, double-blind RCT was conducted at a regional hospital in Taiwan between December 2015 and February 2020. Standard WE and air insufflation were performed. After cecal intubation, the second blinded endoscopist examined the right colon and obtained rADR (primary outcome) and rSLDR. Then, the primary colonoscopist reinserted the scope to the cecum with WE in both groups and performed a tandem examination of the right colon to obtain rAMR.

RESULTS

There were 284 patients (50.9% male, mean age 58.9 ± 9.4 years) who were randomized to WE (n = 144) or air insufflation (n = 140). The baseline characteristics were similar. The rADR (34.7% vs. 22.3%, p = 0.025), Boston Bowel Preparation Scale scores (mean, 2.6 ± 0.6vs. 2.2 ± 0.6, p < 0.001), rSLDR (18.1% vs. 7.1%, p = 0.007), and rAMR (31.5% vs. 45.2%, p = 0.038) were significantly different between WE and air insufflation.

CONCLUSIONS

The current study demonstrated a significantly higher rADR and rSLDR with the WE method performed by blinded colonoscopists. The impact of the significant findings in this report on the occurrence of interval cancers deserves to be studied.

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.

Artificial intelligence and colonoscopy − enhancements and improvements

Artificial intelligence is a technology that processes and analyzes information with reproducibility and accuracy. Its application in medicine, especially in the field of gastroenterology, has great potential to facilitate in diagnosis of various disease states. Currently, the role of artificial intelligence as it pertains to colonoscopy revolves around enhanced polyp detection and characterization. The aim of this article is to review the current and potential future applications of artificial intelligence for enhanced quality of detection for colorectal neoplasia.

Patient, Physician, and Procedure Characteristics Are Independently Predictive of Polyp Detection Rates in Clinical Practice

BACKGROUND

Variability in colon polyp detection impacts patient outcomes. However, the relative influence of physician, patient, and procedure-specific factors on polyp detection is unclear. Therefore, determining how these factors contribute to adenoma and sessile serrated polyp (SSP) detection is important to contextualize measures of colonoscopy quality such as adenoma detection rate and patient outcomes.

AIMS

To determine the relative contribution of physician, patient, and procedure-specific factors in total polyp, adenoma, and SSP detection rates.

METHODS

We performed a retrospective study of patients undergoing screening colonoscopy and used a two-level generalized linear mixed regression model to identify factors associated with polyp detection.

RESULTS

7799 average risk screening colonoscopies were performed between July 2016 and October 2017. The patient factor most strongly associated with increased risk of adenoma and sessile serrated polyp detection was white race (OR 1.21, 95% CI 1.05-1.39 and OR 3.17, 95% CI 2.34-4.30, respectively). Adenomatous (OR 1.92, 95% CI 1.04-3.57) and sessile serrated polyps (OR 5.56, 95% CI 1.37-20.0) were more likely to be found during procedures performed with anesthesia care as compared to those with moderate sedation. Physician with a luminal gastrointestinal focus had increased odds of adenoma detection (OR 1.61, 95% CI 1.02-2.50).

CONCLUSIONS

In a multi-level model accounting for clustering effects, we identified patient, provider and procedural factors independently influence adenoma and sessile serrated polyp detection. Our findings suggest that to compare polyp detection rates between endoscopists, even at the same institution, risk adjustment by characteristics of the patient population and practice is necessary.

Reducing adenoma miss rate of colonoscopy assisted by artificial intelligence: a multicenter randomized controlled trial

BACKGROUND

We have developed the computer-aided detection (CADe) system using an original deep learning algorithm based on a convolutional neural network for assisting endoscopists in detecting colorectal lesions during colonoscopy. The aim of this study was to clarify whether adenoma miss rate (AMR) could be reduced with CADe assistance during screening and surveillance colonoscopy.

METHODS

This study was a multicenter randomized controlled trial. Patients aged 40 to 80 years who were referred for colorectal screening or surveillance at four sites in Japan were randomly assigned at a 1:1 ratio to either the "standard colonoscopy (SC)-first group" or the "CADe-first group" to undergo a back-to-back tandem procedure. Tandem colonoscopies were performed on the same day for each participant by the same endoscopist in a preassigned order. All polyps detected in each pass were histopathologically diagnosed after biopsy or resection.

RESULTS

A total of 358 patients were enrolled and 179 patients were assigned to the SC-first group or CADe-first group. The AMR of the CADe-first group was significantly lower than that of the SC-first group (13.8% vs. 36.7%, P < 0.0001). Similar results were observed for the polyp miss rate (14.2% vs. 40.6%, P < 0.0001) and sessile serrated lesion miss rate (13.0% vs. 38.5%, P = 0.03). The adenoma detection rate of CADe-assisted colonoscopy was 64.5%, which was significantly higher than that of standard colonoscopy (53.6%; P = 0.036).

CONCLUSION

Our study results first showed a reduction in the AMR when assisting with CADe based on deep learning in a multicenter randomized controlled trial.

Overtreatment in nonmalignant lesions detected in a colorectal cancer screening program: a retrospective cohort study

Background

Although colorectal cancer (CRC) screening programs reduce CRC incidence and mortality, they are associated with risks in healthy subjects. However, the risk of overtreatment and overdiagnosis has not been determined yet. The aim of this study was to report the surgery rates in patients with nonmalignant lesions detected within the first round of a fecal immunochemical test (FIT) based CRC screening program and the factors associated with it.

Methods

We included in this analysis all patients with nonmalignant lesions detected between May 2013 and June 2019 in the Galician (Spain) CRC screening program. We calculated surgery rate according to demographic variables, the risk classification according to the colonoscopy findings (European guidelines for quality assurance), the endoscopist’s adenoma detection rate (ADR) classified into quartiles and the hospital’s complexity level. We determined which variables were independently associated with surgery rate and expressed the association as Odds Ratio and its 95% confidence interval (CI).

Results

We included 15,707 patients in the analysis with high (19.9%), intermediate (26.9%) low risk (23.3%) adenomas and normal colonoscopy (29.9%) detected in the analyzed period. Colorectal surgery was performed in 162 patients (1.03, 95% CI 0.87–1.19), due to colonoscopy complications (0.02, 95% CI 0.00–0.05) and resection of colorectal benign lesions (1.00, 95% CI 0.85–1.16). Median hospital stay was 6 days with 17.3% patients developing minor complications, 7.4% major complications and one death. After discharge, complications developed in 18.4% patients. In benign lesions, an endoscopic resection was performed in 25.4% and a residual premalignant lesion was detected in 89.9%. The variables independently associated with surgery in the multivariable analysis were age (≥60 years = 1.57, 95% CI 1.11–2.23), sex (female = 2.10, 95% CI 1.52–2.91), the European guidelines classification (high risk = 67.94, 95% CI 24.87–185.59; intermediate risk = 5.63, 95% CI 1.89–16.80; low risk = 1.43; 95% CI 0.36–5.75), the endoscopist’s ADR (Q4 = 0.44, 95% CI 0.28–0.68; Q3 = 0.44, 95% CI 0.27–0.71; Q2 = 0.71, 95% CI 0.44–1.14) and the hospital (tertiary = 0.54, 95% CI 0.38–0.79).

Conclusions

In a CRC screening program, the surgery rate and the associated complications in patients with nonmalignant lesions are low, and related to age, sex, endoscopic findings, endoscopist’s ADR and the hospital’s complexity.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08606-w.

Utility of artificial intelligence in colonoscopy

Colorectal cancer is one of the major causes of death worldwide. Colonoscopy is the most important tool that can identify neoplastic lesion in early stages and resect it in a timely manner which helps in reducing mortality related to colorectal cancer. However, the quality of colonoscopy findings depends on the expertise of the endoscopist and thus the rate of missed adenoma or polyp cannot be controlled. It is desirable to standardize the quality of colonoscopy by reducing the number of missed adenoma/polyps. Introduction of artificial intelligence (AI) in the field of medicine has become popular among physicians nowadays. The application of AI in colonoscopy can help in reducing miss rate and increasing colorectal cancer detection rate as per recent studies. Moreover, AI assistance during colonoscopy has also been utilized in patients with inflammatory bowel disease to improve diagnostic accuracy, assessing disease severity and predicting clinical outcomes. We conducted a literature review on the available evidence on use of AI in colonoscopy. In this review article, we discuss about the principles, application, limitations, and future aspects of AI in colonoscopy.

Comparative Effectiveness of Commercial Bowel Preparations in Ambulatory Patients Presenting for Screening or Surveillance Colonoscopy

BACKGROUND

Inadequate bowel preparation (IBP) is associated with reduced adenoma detection. However, limited research has examined the impact of different commercial bowel preparations (CBPs) on IBP and adenoma detection. We aim to determine whether type of CBP used is associated with IBP or adenoma detection.

METHODS

We retrospectively evaluated outpatient, screening or surveillance colonoscopies performed in the Cleveland Clinic health system between January 2011 and June 2017. IBP was defined by the Aronchick scale. Multilevel mixed-effects logistic regression was performed to assess the association between CBP type and IBP and adenoma detection. Fixed effects were defined as demographics, comorbidities, medication use, and colonoscopy factors. Random effect of individual endoscopist was considered.

RESULTS

Of 153,639 colonoscopies, 75,874 records met inclusion criteria. Median age was 54; 50% were female; 17.7% had IBP, and adenoma detection rate was 32.6%. In adjusted analyses, compared to GoLYTELY, only NuLYTELY [OR 0.66 (95% CI 0.60, 0.72)] and SuPREP [OR 0.53 (95% CI 0.40, 0.69)] were associated with reduced IBP. Adenoma detection did not vary based on the type of bowel preparation used.

CONCLUSIONS

Among patients referred for screening or surveillance colonoscopy, choice of CBP was not associated with adenoma detection. Decisions about CBP should be based on other factors, such as tolerability, cost, or safety.

Impact of second forward-view examination on adenoma detection rate during unsedated colonoscopy: a randomized controlled trial

Objectives

Colorectal cancer on the right side of the colon has been suggested to be harder to detect by colonoscopy. The aim of this study was to evaluate whether a second forward-view examination of the right side of the colon could increase the adenoma detection rate (ADR) and/or polyp detection rate (PDR).

Methods

This was a single-centre randomized controlled trial. Patients undergoing colonoscopy were recruited and randomly assigned to the second forward-view examination (SFE) group, in which the right side of the colon was examined twice or the traditional colonoscopy (TC) group in which the colonoscopy was performed in a standard manner. The primary outcome was the ADR of right colon. The overall PDR and ADR, PDR of the right colon, per-adenoma miss rate of the right colon, and advanced lesion detection rate were also recorded and compared.

Results

A total of 392 patients were included in the study (SFE group 197 vs. TC group 195). The ADR and PDR of the right colon in the SFE group were significantly higher than those in the TC group (ADR 10.7% vs. 5.1%; P = 0.042); PDR 17.8% vs. 9.7%, P = 0.021). No significant difference was found in overall PDR/ADR, or advanced lesion detection rate between the two groups.

Conclusions

This prospective controlled study revealed that a second forward-view examination could modestly increase the ADR and PDR of the right colon during unsedated colonoscopies. This simple, safe and time-effective technique might be recommended for routine unsedated colonoscopy.

Trial registration: Clinical Trials.gov, NCT03619122. Registered on 7/8/2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-01783-9.

Oral IBGard™ Before Colonoscopy: A Single-Center Double-Blinded, Randomized, Placebo-Controlled Trial

BACKGROUND

Peppermint oil is well known to inhibit smooth muscle contractions, and its topical administration during colonoscopy is reported to reduce colonic spasms.

AIMS

We aimed to assess whether oral administration of IBGard™, a sustained-release peppermint oil formulation, before colonoscopy reduces spasms and improves adenoma detection rate (ADR).  METHODS: We performed a single-center randomized, double-blinded, placebo-controlled trial. Patients undergoing screening or surveillance colonoscopies were randomized to receive IBGard™ or placebo. The endoscopist graded spasms during insertion, inspection, and polypectomy. Bowel preparation, procedure time, and time of drug administration were documented. Statistical analysis was performed using the Student's t test and Wilcoxon rank-sum test.

RESULTS

There was no significant difference in baseline characteristics or dose-timing distribution between IBGard™ and placebo groups. Similarly, there was no difference in ADR (IBGard™ = 47.8%, placebo = 43.1%, p = 0.51), intubation spasm score (1.23 vs 1.2, p = 0.9), withdrawal spasm score (1.3 vs 1.23, p = 0.72), or polypectomy spasm score (0.52 vs 0.46, p = 0.69). Limiting the analysis to patients who received the drug more than 60 min prior to the start of the procedure did not produce any significant differences in these endpoints.

CONCLUSIONS

This randomized controlled trial failed to show benefit of orally administered IBGard™ prior to colonoscopy on the presence of colonic spasms or ADR. Because of its low barrier to widespread adoption, the use of appropriately formulated and timed oral peppermint oil warrants further study to determine its efficacy in reducing colonic spasms and improving colonoscopy quality.

Longer Withdrawal Time Is More Important than Excellent Bowel Preparation in Colonoscopy of Adequate Bowel Preparation

BACKGROUND

Adequate bowel preparation is crucial for effective screening colonoscopy. However, it is unclear whether higher bowel preparation scores correspond to beneficial effects on the adenoma and polyp detection rate (ADR and PDR) in the adequate bowel preparation group.

AIMS

This study aimed to evaluate the effects of bowel preparation, according to the Boston Bowel Preparation Scale (BBPS), and colonoscopy withdrawal time (CWT) on ADR and PDR in the adequate bowel preparation group.

METHODS

Healthy examinees between 50 and 75 years old who underwent colonoscopy between September 2015 and August 2016 were included. BBPS scores, CWT, ADR, and PDR were reviewed retrospectively. Predictors of ADR and PDR were analyzed with a generalized linear mixed model.

RESULTS

A total of 5073 cases with adequate bowel preparation (BBPS ≥ 6) were analyzed. Examinees with good (BBPS = 6, 7) and excellent (BBPS = 8, 9) bowel preparation were 1898 (37.4%) and 3175 (62.6%), respectively. Both ADR and PDR were higher in the good bowel preparation group than in the excellent bowel preparation group (ADR 47.3% vs. 45.0%, P = 0.035; PDR 73.7% vs. 69.5%, P = 0.004, respectively). In the multivariate analysis, CWT, rather than BBPS, was significantly associated with both ADR (OR 1.04; 95% CI 1.02-1.06; P < 0.001) and PDR (OR 1.05; 95% CI 1.02-1.07; P = 0.002).

CONCLUSIONS

Both ADR and PDR were lower when bowel preparation was excellent rather than good. However, CWT, not BBPS, was significantly associated with ADR and PDR in the adequate bowel preparation group. Therefore, meticulous inspection is important for high-quality colonoscopy regardless of the BBPS score in examinees with adequate bowel preparation.

Effects of L-Menthol and Carbon Dioxide on the Adenoma Detection Rate during Colonoscopy: L-Menthol and Carbon Dioxide on Colonoscopy

BACKGROUND AND AIMS

We examined the efficacy of the combined use of L-menthol spraying (L-mentholS) as an antispasmodic agent and carbon dioxide insufflation (CO2I) on the adenoma detection rate (ADR) in a prospective, single-center trial with a 2 × 2 factorial design.

METHODS

We randomly assigned 611 patients scheduled to undergo colonoscopy to 4 groups: (1) the L-mentholS + CO2I (n = 153), (2) L-mentholS + air insufflation (AI; n = 156), (3) CO2I (n = 153), and (4) AI (n = 149) groups. We used 20 mL of 0.8%-L-menthol solution for the L-mentholS. The primary outcome was the difference in the ADR, and the secondary outcomes were the differences in colonic peristalsis and abdominal pain. -Results: The ADRs were not different among the groups: 1/2/3/4; 39.9%/43.6%/41.2%/51.0%. CO2I was associated with a significant decrease in the ADR (OR 0.57; 95% CI 0.35- 0.93) with a multiple logistic regression. The interaction between L-mentholS and CO2I was associated with a suppression of the decrease in the ADR. Both L-mentholS and CO2I were associated with a significant decrease in abdominal pain, and L-mentholS was associated with a significant improvement of peristalsis.

CONCLUSIONS

The fact that CO2I was associated with significant decreases in the ADR was a problem. The combined use of L-mentholS and CO2I could help to suppress the decrease in the ADR.

Oral indigo carmine for the detection of colon adenoma

OBJECTIVES

Colonoscopy is currently considered the optimal method to detect colorectal neoplasia; however, some adenomas remain undetected. While indigo carmine staining with a dye-spray catheter has demonstrated promising results for reducing the miss rate, we investigated the oral indigo carmine method. The aim of this study was to determine whether oral indigo carmine intake before standard colonoscopy increases the adenoma (and adenocarcinoma) detection rate (ADR) or the mean number of adenomas per patient (MAP).

MATERIALS AND METHODS

The oral indigo carmine method was performed from April 2018 to July 2020 in two hospitals. Data were collected in a prospective manner and compared to the conventional group whose data were collected retrospectively and consecutively from January 2016 to March 2018. All data were anonymized.

RESULTS

Among the 704 patients included, colonoscopies were completely performed in 693 patients (347 in the indigo group). The ADR did not significantly differ between the groups: 42.3% vs. 40.3% (indigo vs. conventional group; odds ratio: 1.13; 95% confidence interval: 0.9-1.33, p = .33). The MAP was significantly greater in the indigo group (1.15) than that in the conventional group (0.82; p = .009). The cecal intubation rate and time to cecal intubation did not differ between the indigo and conventional group (98.6% vs. 98.3%, p = .83, and 6.2 min vs. 5.9 min, p = .39, respectively).

CONCLUSION

The routine use of oral indigo carmine does not lead to a higher ADR despite the higher MAP.

Screening colonoscopy: The present and the future

In the United States, colorectal cancer (CRC) is the second leading cause of mortality in men and women. We are now seeing an increasing number of patients with advanced-stage diagnosis and mortality from colorectal cancer before 50 years of age, which requires earlier screening. With the increasing need for CRC screening through colonoscopy, and thus endoscopists, easier and simpler techniques are needed to train proficient endoscopists. The most widely used approach by endoscopists is air insufflation colonoscopy, where air distends the colon to allow visualization of the colonic mucosa. This technique is un-comfortable for patients and requires an anesthetist to administer sedation. In addition, patients commonly complain about discomfort post-op as air escapes into the small bowel and cannot be adequately removed. Current research into the use of water insufflation colonoscopies has proved promising in reducing the need for sedation, decreasing discomfort, and increasing the visibility of the colonic mucosa. Future direction into water insufflation colonoscopies which have shown to be simpler and easier to teach may increase the number of proficient endoscopists in training to serve our aging population.