Introduction

The quality of a colonoscopy is heavily reliant on the effectiveness of bowel cleansing, which can impact the diagnostic accuracy and identification of adenomas. Various bowel cleansing products have been suggested, but their comparative effectiveness remains uncertain.

Aims & Methods

This systematic review and network meta-analysis aims to compare the performance of different bowel preparations for colonoscopy. MEDLINE, Embase, Scopus, and the Cochrane Library were systematically searched for randomized controlled trials (RCTs) comparing the efficacy of different bowel preparations administered as split or same-day regimen. The primary outcome was cleansing success (CS) defined as a total BBPS score of ≥6. The secondary outcome was ADR.

Results

On network meta-analysis for CS (22 RCTs, 7179 patients, 14 bowel preparations assessed), 2L PEG+simethicone (RR=1.25 [95%CI=1.13-1.37]), 2L PEG+lactulose (RR=1.22 [95%CI=1.10-1.38]) and 1L PEG+ascorbate (ASC) (RR=1.03 [95%CI=1.01-1.06]) were significantly superior to 2L PEG+ASC. Overall, 2L PEG+lactulose resulted as the best product (SUCRA 0.94), followed by 2L PEG+simethicone (SUCRA 0.93), whereas 2L PEG+ASC showed the poorest performance. On network meta-analysis for ADR (17 RCTs, 6639 patients, 11 bowel preparations assessed), only 2L PEG+simethicone (RR=1.60 [95%CI=1.05-2.43]) resulted significantly superior to 2L PEG + ASC.

Conclusion

2L PEG+simethicone, 2L PEG+lactulose, and 1L PEG+ASC seemed to provide high rates of cleansing success, albeit only 2L PEG+simethicone was associated with a significantly higher ADR. Consequently, these products should be preferred for bowel preparation of colonoscopy. Further randomized studies with adequate sample sizes are needed for a more accurate comparison of these products on ADR.

Introduction

Endoscopic submucosal dissection (ESD) is an advanced technique that can provide a successful ‘en-bloc’ and R0 resection rate for large gastrointestinal (GI) lesions. To date, several ESD techniques have been proposed, but their comparative efficacy is still unclear.

Aims & Methods

This network meta-analysis aims to investigate and compare the efficacy and safety of different ESD techniques for resection of colonic lesions. MEDLINE, Embase, Scopus, and the Cochrane Library were systematically searched for randomized controlled trials (RCTs) comparing different ESD techniques through March 2024. The primary outcomes were ‘en-bloc’ and R0 resection rates. The secondary outcome was the incidence of procedure-related AEs. Direct and indirect comparisons were performed among different ESD techniques. Results were expressed as risk ratio (RR) and 95% confidence interval (CI), using the DerSimonian and Laird random-effects model. The relative ranking of the interventions for achieving the aforementioned outcomes was calculated as their surface under the cumulative ranking curve (SUCRA). The study quality was evaluated using the revised Cochrane risk-of-bias (RoB2) tool for randomized trials.

Results

After selection of studies, 9 RCTs were included in the systematic review.
On network meta-analysis for ‘en-bloc’ resection (9 RCTs, 872 patients, 5 techniques assessed), pocked with traction ESD (PT-ESD) (RR=1.02 - 95%CI=0.96-1.07) and pocket ESD (P-ESD) (RR=1.02 - 95%CI=0.98-1.05) showed higher efficacy, whereas hybrid ESD (H-ESD) (RR=0.94 - 95%CI=0.87-1.02) lower efficacy compared to conventional ESD (C-ESD).
On network meta-analysis for R0 resection (7 RCTs, 732 patients, 4 techniques assessed), PT-ESD (RR=1.05 - 95%CI=0.96-1.16) showed higher efficacy, and H-ESD (RR=0.97 - 95%CI=0.84-1.13) lower efficacy compared to C-ESD. Overall, P-ESD resulted the best technique for ‘en-bloc’ resection (SUCRA 0.70) and PT-ESD for R0 (SUCRA 0.83), while H-ESD showed the poorest performance for both outcomes (SUCRA 0.06 and 0.30, respectively) (Table 1).
On network meta-analysis for AEs (9 RCTs, 872 patients, 5 techniques assessed), PT-ESD (RR=0.35 - 95%CI=0.05-2.48) was associated with a lower incidence of AEs, and H-ESD (RR=1.22 - 95%CI=0.30-5.01) with higher incidence of AEs, compared to C-ESD. Overall, PT-ESD resulted as the safest technique (SUCRA 0.83), followed by T-ESD (SUCRA 0.60), whereas H-ESD showed the poorest performance (SUCRA 0.28).
According to the RoB2 tool, none of the studies included was of poor methodological quality except for one.


Table 1. SUCRA score ranking of different interventions in terms of ‘en-bloc’ resection rate, R0 resection rate and incidence of AEs.

Conclusion

The results of this network meta-analysis show a trend towards greater effectiveness and safety of PT-ESD for the removal of colonic lesions. H-ESD was associated with worse results and should be avoided, preferring other techniques.

Introduction

AI (artificial intelligence)-driven computer-aided detection (CADe) systems are typically trained using high-quality, standardized colonoscopy images/videos, assuming its use under optimal bowel preparation. However, it remains uncertain how varying levels of bowel cleanliness affect CADe performance.

Aims & Methods

To measure the impact of bowel preparation quality on the adenoma detection capability of CADe systems.
This is a cumulative post-hoc analysis of individual data from three randomized controlled studies with similar design comparing CADe-assisted with standard colonoscopy (SC). Only patients with adequate bowel preparation (Boston Bowel Preparation Scale [BBPS] >2 in each colonic segment) were included. The primary outcome measure was the difference in adenoma detection rate (ADR) and adenoma per colonoscopy (APC) between the CADe-assisted and SC groups, according to the quality level of bowel preparation, classified as good (BBPS 6–7) or excellent (BBPS 8–9).

Results

A total of 2103 patients (1047 CADe, 1056 SC; mean age 61.5 ± 9.2 years; 50.4% male) were included. Bowel preparation was rated as good in 906 patients (43.1%) and excellent in 1197 patients (56.9%). CADe increased ADR and APC compared to SC in both good (52.2% vs. 43.8%; 1.21 vs. 0.93) and excellent (54.5% vs. 43.9%; 1.09 vs. 0.89) bowel preparation groups. The absolute increase in ADR with CADe was +8.4% (95% CI: 1.9–14.9) and +10.6% (95% CI: 5.0–16.2) in good and excellent preparation groups, respectively, with no significant interaction between preparation quality and CADe effect (Δ = +2.2%, 95% CI: -6.4–10.8; interaction p = 0.612). Similarly, APC increases were +0.28 (95% CI: 0.06–0.50) and +0.20 (95% CI: 0.03–0.36) for the good and excellent preparation groups, respectively, without significant interaction observed (Δ = -0.08, 95% CI: –0.22 to +0.06, interaction p = 0.261). Similar trends were observed when the analysis was restricted to the right colon or to diminutive adenomas.

Conclusion

In patients with adequate bowel preparation, CADe improves adenoma detection regardless of cleansing quality grades.

References

1. Repici, A, Badalament M, Maselli R et al. Efficacy of Real-Time Computer-Aided Detection of Colorectal Neoplasia in a Randomized Trial. Gastroenterology 2020; 159: 512–520
2. Repici A, Spadaccini M, Antonelli G, et al. Artificial intelligence and colonoscopy experience: lessons from two randomised trials. Gut 2022; 71: 757-765.
3. Rondonotti E, Di Paolo D, Rizzotto ER, et al. Efficacy of a computer-aided detection system in a fecal immunochemical test-based organized colorectal cancer screening program: a randomized controlled trial (AIFIT study). Endoscopy. 2022; 54: 1171-1179.

Introduction

A good bowel preparation for colonoscopy is fundamental to improve the quality of the examination, reduce procedural complications and achieve optimal polyp detection. Among possible strategies to enhance bowel preparation, visual booklets have been proposed with conflicting results. Therefore we aimed to perform a systematic review with meta-analysis of randomized controlled studies (RCT) to ascertain whether booklets may be useful in this setting.

Aims & Methods

Literature search was performed in July 2022, in main databases (PUBMED, SCOPUS, ScienceDirect, the Cochrane Central Register of Controlled Trials and ClinicalTrials.gov). only RCTs were selected. The primary outcome was the quality of bowel preparation. Further outcomes were the adenoma detection rate (ADR), number of polyps detected per patient, rate of cecal intubation, time of insertion and withdrawal, adverse events, willingness to repeat preparation and colonoscopy. We estimated odd ratios (OR) for dichotomous outcomes. mean differences (MD) or standardized mean differences (SMD) were used for continuous outcomes. We estimated heterogeneity among studies with the Chi2 (Cochran Q) and the I2 statistics. In case of high heterogeneity, a random effect model was used, otherwise a fixed effects model was preferred. All analyses were performed using RevMan version 5.4.1.

Results

Six studies were selected, enrolling overall 1755 patients (857 in the booklet and 898 in the control group). Adequate bowel preparation was achieved in the 86.7% (743 out of 857) of booklet preparation versus the 77.5% (696 out of 898) in the control group, with an OR of 2.31 in favour of booklet (95% CI 1.20-4.45, p = 0.01). Booklet was more effective than control in the transverse colon (MD = 0.37, 95% CI 0.01-0.72, p = 0.03), while no differences were found in right colon and left colon. In four studies a 4-L PEG-based preparation was used and the pooled analysis did not find any difference compared to controls, while when sodium phosphate and magnesium citrate or sodium phosphate or PEG were used, preparation with booklet was better than in controls (OR = 5.10, 95% CI 1.82-14.27, p = 0.002). Two studies were performed in inpatient setting, without difference between booklet and controls while in outpatients patients receiving booklets were better prepared than controls (OR = 7.13, 95% CI 5.39-9.45, p < 0.001). ADR was similar between the two groups, with an OR = 0.93 (95% CI 0.75-1.16, p = 0.53). The mean number of polyps per patient did not differ between the two groups (MD = 0.22, 95% CI -0.14-0.58, p = 0.23).

Conclusion

The present meta-analysis demonstrated that booklets are useful to enhance bowel preparation. Outpatients and non PEG-based preparations seem to benefit more from booklets, while no effect on ADR has been observed.

Introduction

Intubation of the terminal ileum (TI) is the gold standard for completion of colonoscopy.
Our aim was to assess if this objective was achieved in our centre between endoscopists using various bowel preparations.
Poly ethylene glycol 4000 Vs Magnesium sulphate combined with potassium and sodium sulphates were the two commonly used bowel preparations. Magnesium containing preparations must be used with caution and avoided in patients with renal insufficiency, cardiac disease or pre-existing electrolyte abnormality and patients on diuretic therapy.
The Boston Bowel Preparation Scale was developed to limit inter-observer variability in the rating of bowel preparation quality, while preserving the ability to distinguish various degrees of bowel cleanliness and is mainly designed for adults. There is no dedicated bowel preparation score available for paediatric colonoscopies, BBPS is being used for critical comparison in our prospective cohort.

Aims & Methods

Objectives: To compare the intubation rate of TI between two endoscopists with quality of bowel preparation of colonoscopies in a tertiary health care centre and to assess the quality of bowel preparation of individual colonoscopies performed vis-a-vis, Boston bowel preparation scale as a prospective study over a period of 1 year.
Material and methods: A prospective study in a tertiary referral centre in children who underwent colonoscopies, aged 1 month to 17 years over a period of 1 year.
All children whose parents consented were included in the study. Results were collated using Microsoft Excel ™.A total of 135 cases were enrolled during our study period.

Results

1. TI intubation rate in PEG-4000 + bisacodyl based laxative formula is 87%
2. TI intubation rate in Magnesium/sodium/potassium based saline laxative formula is 79%
3. No side effects were encountered/ observed in either of the cohort.

Conclusion

In our study albeit the fact that our endoscopist chose different bowel preparations based on their anecdotal evidence based experience, we found that the bowel preparation was adequate.
There was no standardised paediatric bowel preparation globally and we note that every hospital or department or clinician have devised their own bowel preparation based either on personal experience or current available scientific literature.
We also note that we do not have a BBPS for paediatrics which will of immense value for research evaluation and revalidation of bowel preps.

References

1. Hien PT, Thoi VH, Ha NT, Kalach N. Efficacy of Two Regimens for Colon Cleansing Using Polyethylene Glycol 4000: A Randomized Open Label Trial. Indian Pediatr. 2021 Dec 15;58(12):1119-1123. Epub 2021 May 28.
2. Goodman and Gilman’s The pharmacological basis of therapeutics., 13^th edition
3. Mamula, Petar, and Noor Nema. “Bowel Preparation for Pediatric Colonoscopy.” Frontiers in pediatrics vol. 9 705624. 1 Sep. 2021
4. Barraclough H, Gillett P, Basude D, et al OC68 A multicentre assessment of adequacy of bowel preparation for paediatric ileocolonoscopy using the Boston bowel preparation scale (BBPS) Frontline Gastroenterology 2023;14:A42.

Introduction

Inadequate bowel preparation is linked to reduced adenoma detection rates (ADR), and establishing a threshold for bowel preparation below which colonoscopies should be repeated early is crucial for patient outcomes. However, manual bowel cleansing efficacy evaluation relies on the clinical observer's experience, resulting in subjectivity with clinical and economic implications. The Boston Bowel Preparation Scale (BBPS) is the most validated scoring scale. Our group previously constructed an AI-based bowel preparation assessment model to calculate e-BBPS scores.

Aims & Methods

This prospective, single-center study was conducted at the Eighth Affiliated Hospital, Sun Yat-sen University in China from October 2021 to November 2022. Eligible patients underwent screening colonoscopy by one of three study endoscopists. The AI calculated the e-BBPS score during colonoscope withdrawal. The endoscopist assessed bowel preparation adequacy using BBPS after the colonoscopy. If both BBPS and e-BBPS deemed bowel preparation adequate, the same endoscopist performed a second colonoscopy. If either considered it inadequate, the patient underwent bowel re-cleansing before the second colonoscopy. Video recordings were evaluated for bowel preparation using BBPS by five independent endoscopist raters.

Results

From October 8, 2021, to November 9, 2022, a total of 393 patients were included for analysis. In patients with unqualified-AI, the >5mm AMR was significantly higher than in patients with qualified-AI (p=0.0056, OR 0.2734, 95% CI 0.1139, 0.6565), as were the AMR <0.001 (p=0.2532, 95% CI 0.1583, 0.4052), diminutive AMR (p<0.001, OR 0.2160, 95% CI 0.1206, 0.3867), >5mm PMR (p=0.0152, OR 0.4335, 95% CI 0.2288, 0.8213), and PMR (p <0.001, OR 0.4532, 95% CI 0.3447, 0.5958). No significant differences were observed in the overall >5mm ADR, ADR, >5mm PDR, and PDR. In the first pass, no statistical differences were found in ADR between the qualified-AI and unqualified-AI groups, though there was a trend toward a higher ADR in the qualified-AI group. In the second pass, patients in the qualified-AI group achieved significantly lower >5mm ADR, ADR, diminutive ADR, advanced ADR, >5mm PDR, and PDR compared to those in the unqualified-AI group.
Cohen's kappa analysis revealed high agreement between expert raters, clinical scoring, and e-BBPS (ranging from 0.7791 to 0.8322). However, the agreement between general endoscopists and other raters was only low to moderate (0.2937 to 0.6071). Fleiss' kappa also indicated that the overall agreement among all raters was only 0.575 (p < 0.001, 95% CI 0.574, 0.575), while the Fleiss' kappa for Expert and Clinical scoring, as well as Expert, Clinical scoring, and e-BBPS were 0.809 (p < 0.001, 95% CI 0.807, 0.810) and 0.800 (p < 0.001, 95% CI 0.799, 0.801), respectively.

Conclusion

This study validates the e-BBPS bowel preparation evaluation threshold, confirming that patients with a score of ≤3 have adequate bowel preparation for detecting >5mm adenomatous polyps, while those with a score of >3 require repeat bowel preparation. This conclusion supports the implementation and promotion of fully automated bowel preparation assessment systems, which may improve the objectivity of bowel preparation evaluation and standardize clinical practice for screening colonoscopies in the future.

Introduction

One-fourth of colorectal neoplasia is missed at screening colonoscopy, representing the leading cause of interval colorectal cancer (I-CRC). Colonoscopy assisted by artificial intelligence (AI) with computer-aided polyp detection (CADe) showed higher adenoma detection rate (ADR) and higher adenoma per colonoscopy compared to white light (WL) colonoscopy in randomized clinical trials (RCTs). Despite ADR is a reliable quality indicator and has been associated to the risk of I-CRC and death, an adequate ADR does not eliminate the risk of lesion miss rate since the relationship between ADR and adenoma miss rate (AMR) is only indirect.

Aims & Methods

The aim of this meta-analysis is to summarise the performance of CADe systems on miss rate of colonic lesions. PubMed/Medline, Embase and Cochrane Library were systematically searched through October 2022 by two independent reviewers (M.M. and A.F.) for tandem-design RCTs comparing miss rate of colonic lesions in CAD-first colonoscopy followed by WL colonoscopy (experimental arm) vs WL-first colonoscopy followed by CAD colonoscopy (control arm).
The primary outcomes were pooled AMR and polyp miss rate (PMR). Secondary outcomes were advanced adenoma miss rate (aAMR) and sessile serrated lesion miss rate (SMR). Lesion miss rate was defined as the number of lesions detected at second colonoscopy divided by the total number of same lesions detected at first and second colonoscopy. A random-effect model was applied for pooling results. Heterogeneity was expressed as I².

Results

Overall, 4 RCTs (1166 patients), were included in the analysis. Pooled AMR was significantly lower in the CAD-first compared to WL-first arm (131/842, 15.5% vs 300/857, 35.0%; RR, 0.45; 95% CI, 0.35-0.58; P<0.001; I²=49%). PMR was also lower in the CAD-first compared to WL-first arm (192/1198, 16.0% vs 474/1244, 38.1%; RR, 0.43; 95% CI, 0.30-0.61; P<0.001; I²=82%).
No significant difference in aAMR (2/23, 8.7% vs 5/32, 15.6%; RR, 1.28; 95% CI, 0.34-4.83; P=0.71; I²=0%) and in SMR (5/43, 11.6% vs 27/67, 40.3%; RR, 0.44; 95% CI, 0.15-1.28; P=0.13; I²=46%) were observed.

Table 1. Characteristics of the studies included in the meta-analysis.

Conclusion

According to available evidence, the use of colonoscopy assisted by AI with CADe results in a significant lower AMR and PMR, with a potential implication in reducing the incidence of I-CRC. No significant difference in aAMR and SMR has been observed, even if these results should be further confirmed in studies with larger sample sizes.