Serrated polyps can progress to colorectal cancer (CRC), through a pathway that is distinct from the conventional adenoma-carcinoma sequence. This pathway includes hyperplastic polyps (HPs), sessile serrated polyps (SSPs), and traditional serrated adenomas (TSAs).

Our review includes the histology and pathological challenges, carcinogenesis, risk factors, detection, emerging technologies, resection, and surveillance.

Serrated polyp management presents many detection, diagnosis, resection, and surveillance challenges. Missed serrated polyps contribute to preventable CRCs. A new SSP detection rate benchmark will guide endoscopists with a goal when improving detection. Furthermore, new SSP-specific surveillance strategies may also aid in reducing CRC burden. Histologic differentiation remains a challenge, underscoring the need for standardized pathology practices and exploring novel ways to stratify risk independent of histology, given interobserver variation. Moreover, the clinical significance of proximal HPs requires further clarification. Which HPs < 1 cm require closer surveillance intervals? Molecular profiling may help identify markers that separate proximal low risk from high-risk HP. The best approach for resection of serrated polyps also needs to be clarified. There is also a lack of robust longitudinal outcome data to guide surveillance recommendations since current guidelines are based on low quality of evidence.

Adequate bowel preparation and tagging are critical in optimizing CTC performance. Iohexol has a higher safety profile than other available tagging agents. This study aims to determine if iohexol serves as an adequate fluid and stool tagging agent in conjunction with minimally cathartic bowel preparation.

In this prospective observational study, 50 participants ingested 50 mL of oral iohexol for tagging and 10 oz magnesium citrate for bowel preparation prior to CTC. Written informed consent was obtained. CTC was performed in all participants in at least two of the standard four positions (supine, prone, right decubitus, and left decubitus). Two board-certified abdominal radiologists independently scored the 6 colonic segments of participants who underwent successful CTC. The amount of residual fluid and solid stool, attenuation of tagged fluid, and efficacy of fluid and stool tagging were recorded in each segment. Statistical analyses were performed with R-4.4.0.

47 participants (mean age 66.39 ± 8.65 years; 39 female) underwent successful CTC. Of 1252 total colonic segments, 14.8% had no residual fluid and 59.5% had < 25% residual fluid. 73.6% of segments with residual fluid demonstrated good tagging. The mean fluid tagging efficacy ratio for all segments was 0.737 (95% CI: 0.700-0.775) with mean attenuation of 467 HU. Fluid tagging efficacy decreased from the cecum (0.934) to rectum (0.493). 92.8% of segments had no residual solid stool. Of the 7.2% of segments containing solid stool, 4.7% of segments had submerged stool ≤ 5 mm, 0.8% had 1-3 pieces of retained stool between 6 and 9 mm, and 1.8% had > 3 pieces 6-9 mm or single pieces > 1 cm.

Low-volume (50 mL) iohexol is an effective fluid and fecal tagging agent for CTC with a minimally cathartic bowel preparation. This provides an easy option to label residual material and cleanse the bowel for patients undergoing CTC.

Background: Colonoscopy is crucial for diagnosing and monitoring inflammatory bowel disease (IBD), assessing disease activity, and detecting dysplasia. However, patient adherence to surveillance remains suboptimal due to discomfort, anxiety, and concerns about bowel preparation. Methods: This multicenter cross-sectional study assessed patient satisfaction with colonoscopy in IBD patients across three Italian centers. Participants completed pre- and post-examination questionnaires, including the Endoscopy Customer Satisfaction Questionnaire (ECSQ) and Perceived Stress Scale (PSS-10). Clinical factors, bowel preparation methods, and healthcare provider expertise were analyzed. Results: Among 444 enrolled patients, overall satisfaction was high (98.8%) but varied across procedural phases. Higher satisfaction was predicted by expert endoscopists (β = 2.11, p = 0.012), disease remission (β = 1.70, p = 0.020), and frequent endoscopic procedures in the last 24 months (β = 0.46, p = 0.041). Conversely, severe disease activity (β = -3.87, p < 0.001) was associated with lower satisfaction. Deep sedation and high-volume bowel preparation negatively impacted satisfaction. Conclusions: Optimizing bowel preparation, enhancing healthcare provider expertise, and implementing stress-reducing strategies could improve patient adherence to surveillance guidelines in IBD care.

This document is an update to the 2014 recommendations for optimizing the adequacy of bowel cleansing for colonoscopy from the US Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. The US Multi-Society Task Force developed consensus statements and key clinical concepts addressing important aspects of bowel preparation for colonoscopy. The majority of consensus statements focus on individuals at average risk for inadequate bowel preparation. However, statements addressing individuals at risk for inadequate bowel preparation quality are also provided. The quality of a bowel preparation is defined as adequate when standard screening or surveillance intervals can be assigned based on the findings of the colonoscopy. We recommend the use of a split-dose bowel preparation regimen and suggest that a 2 L regimen may be sufficient. A same-day regimen is recommended as an acceptable alternative for individuals undergoing afternoon colonoscopy, but we suggest that a same-day regimen is an inferior alternative for individuals undergoing morning colonoscopy. We recommend limiting dietary restrictions to the day before a colonoscopy, relying on either clear liquids or low-fiber/low-residue diets for the early and midday meals. We suggest the adjunctive use of oral simethicone for bowel preparation before colonoscopy. Routine tracking of the rate of adequate bowel preparations at the level of individual endoscopists and at the level of the endoscopy unit is also recommended, with a target of >90% for both rates.

This document is an update to the 2014 recommendations for optimizing the adequacy of bowel cleansing for colonoscopy from the US Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology, the American Gastroenterological Association, and the American Society for Gastrointestinal Endoscopy. The US Multi-Society Task Force developed consensus statements and key clinical concepts addressing important aspects of bowel preparation for colonoscopy. The majority of consensus statements focus on individuals at average risk for inadequate bowel preparation. However, statements addressing individuals at risk for inadequate bowel preparation quality are also provided. The quality of a bowel preparation is defined as adequate when standard screening or surveillance intervals can be assigned based on the findings of the colonoscopy. We recommend the use of a split-dose bowel preparation regimen and suggest that a 2 L regimen may be sufficient. A same-day regimen is recommended as an acceptable alternative for individuals undergoing afternoon colonoscopy, but we suggest that a same-day regimen is an inferior alternative for individuals undergoing morning colonoscopy. We recommend limiting dietary restrictions to the day before a colonoscopy, relying on either clear liquids or low-fiber/low-residue diets for the early and midday meals. We suggest the adjunctive use of oral simethicone for bowel preparation before colonoscopy. Routine tracking of the rate of adequate bowel preparations at the level of individual endoscopists and at the level of the endoscopy unit is also recommended, with a target of >90% for both rates.

Colonoscopy is the gold standard for early detection and monitoring of colorectal cancer. Procedural effectiveness is dependent on optimal bowel preparation. Traditional polyethylene glycol (PEG) solutions are difficult to tolerate, whereas newer low-volume alternatives, including PEG with ascorbic acid and oral sulfate solutions (OSS), offer improved efficacy and tolerability. The meta-analysis was performed to evaluate the efficacy and safety of OSS compared to PEG for bowel preparation in colonoscopy.

Studies were identified by searching PubMed, Embase, Cochrane CENTRAL, and clinicaltrials.gov from inception until June 2024. Only randomized controlled trials comparing OSS with PEG were included. Data was analyzed using R version 4.4.0 using a random effects model to calculate risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs).

Twenty-one studies with 6346 participants met the inclusion criteria. OSS significantly improved adenoma detection (RR, 1.13; 95% CI, 1.04-1.22; p-value <0.01; I2 = 0%) and polyp detection rates (RR, 1.16; 95% CI, 1.06-1.26; p-value <0.01; I2 = 0%), and had a higher Boston Bowel Preparation Scale (BBPS) score (MD, 0.31; 95% CI, 0.13-0.50; p-value <0.01; I2 = 81%). PEG was associated with more sleep disturbances (RR, 0.45; 95% CI, 0.25-0.82; p-value = 0.03; I2 = 0%). However, other adverse effects were similar between both solutions.

OSS demonstrated superior adenoma and polyp detection rates. When compared to PEG, patients utilizing OSS achieved higher BBPS scores. Data gleaned support enhanced cleansing efficacy and safety of OSS as a bowel preparation regimen.

This document is an update to the 2014 recommendations for optimizing the adequacy of bowel cleansing for colonoscopy from the US Multi-Society Task Force on Colorectal Cancer, which represents the American College of Gastroenterology and the American Society for Gastrointestinal Endoscopy. The US Multi-Society Task Force developed consensus statements and key clinical concepts addressing important aspects of bowel preparation for colonoscopy. The majority of consensus statements focus on individuals at average risk for inadequate bowel preparation. However, statements addressing individuals at risk for inadequate bowel preparation quality are also provided. The quality of a bowel preparation is defined as adequate when standard screening or surveillance intervals can be assigned based on the findings of the colonoscopy. We recommend the use of a split-dose bowel preparation regimen and suggest that a 2 L regimen may be sufficient. A same-day regimen is recommended as an acceptable alternative for individuals undergoing afternoon colonoscopy, but we suggest that a same-day regimen is an inferior alternative for individuals undergoing morning colonoscopy. We recommend limiting dietary restrictions to the day before a colonoscopy, relying on either clear liquids or low-fiber/low-residue diets for the early and midday meals. We suggest the adjunctive use of oral simethicone for bowel preparation before colonoscopy. Routine tracking of the rate of adequate bowel preparations at the level of individual endoscopists and at the level of the endoscopy unit is also recommended, with a target of >90% for both rates.

The quality of a colonoscopy is heavily reliant on the effectiveness of bowel cleansing. Various cleansing solutions are currently available, but their comparative efficacy remains uncertain. 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. The primary outcome was cleansing success (CS), and the secondary outcome was adenoma detection rate (ADR).

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

2 L PEG + simethicone, 2 L PEG + lactulose, and 1 L PEG + ASC seemed to provide high rates of CS, albeit only 2 L PEG + simethicone was associated with 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.

The carcinogenesis of colorectal cancer is well understood. Adenomas are the precursor lesions in about 70% of cases, highlighting the importance of screening programs.

The aim of this study was to analyze the effectiveness of colonoscopy examinations performed in a private tertiary service by calculating the polyp detection rate (PDR) and adenoma detection rate (ADR) and comparing these rates with literature data.

This retrospective observational study evaluated colonoscopies performed at Hospital Centro Médico de Campinas between 2018 and 2020. It assessed the indications and complications of colonoscopy, sex, age group, bowel preparation, cecal intubation rate, ADR, PDR, and advanced adenoma detection rate (AADR).

During the period, 3,686 colonoscopies were performed, and 3,076 were included in the analysis. The mean patient age was 57.2 years, and most patients were female (53.5%). Complications occurred in 39 colonoscopies (1.3%), with bleeding in six cases and perforation in one case. Tubular adenoma was the most prevalent histological subtype found in 20% of tests and in 62.7% of those with positive findings. The PDR was 23% and significantly increased with advancing age (p<0.01). The ADR was 20% and also significantly increased with age (p<0.001). This rate was higher in men (27%). The AADR was 4%.

Colonoscopy is an effective polyp detection method, and the PDR was higher in men and significantly increased with age. The ADR and AADR were comparable to the literature data.

Despite lower patient adherence, the overnight split-dose (SD) intestinal preparation regimen is currently recommended for early morning colonoscopies. Using low-volume preparation, we compared performance of a "day before late" (DBL) regimen, with the whole preparation taken between 8.30 pm and midnight on the day before the endoscopic procedure vs the overnight SD regimen for colonoscopies scheduled between 8 am and 10 am.

Patients were randomized to the DBL group (n = 162) or SD group (n = 158). The SD group took the second dose 5 hours before colonoscopy. Successful bowel cleansing, defined as an overall Boston Bowel Preparation Score ≥ 3, safety, compliance and tolerability were assessed in the two groups.

The DBL regimen failed to demonstrate non-inferiority compared with the SD regimen in terms of successful bowel cleansing (DBL, 88.2 % vs SD, 98.1%, P < 0.001). Subgroup analysis on colonoscopies before 9 am showed BBPS ≥ 3 rates of 94.6% and 100% in the DBL and SD groups, respectively P = 0.126). The two regimens showed similar compliance and tolerability. Compared with SD patients (25.5%), a lower proportion of DBL patients (13.9%) reported fear of incontinence during the journey to the hospital ( P = 0.01).

Albeit more tolerable, the DBL regimen was less effective than the SD regimen with regard to successful bowel cleansing for colonoscopies between 8 am and 10 am. Subgroup analysis on colonoscopies scheduled before 9 am showed that the two regimens have similar efficacy, suggesting that the DBL regimen may be a valuable alternative to the SD regimen for very early morning colonoscopies.

The quality of bowel preparation is one of the key determinants of a successful colonoscopy. Bowel preparation regimens have evolved greatly over the past few decades, with attempts to improve the efficiency and tolerability; still an ideal agent or regimen continues to be oblivious. To compare the efficacy, safety, and tolerance of three bowel preparation regimens for colonoscopy: split dose of oral sulfate solution (OSS), split dose of polyethylene glycol (PEG), and same-day single dose PEG.

This study was a randomized, single-blind control design with three study groups. Group A received a split dose of OSS, group B received a split dose of PEG, and Group C received a single dose of PEG for bowel preparation. The quality of preparation was assessed using the Boston Bowel Preparation Scale (BBPS), and the adverse effects and tolerance were noted. The data were compared statistically for any significant difference between the regimens.

Mean total BBPS scores were 8.08, 7.52, and 7.92 for groups A, B, and C, respectively (P=0.076). Segmental BBPS scores were statistically similar for the right and transverse colon but differed for the left colon (A: B: C=2.79: 2.54: 2.75; P<0.01). Gastrointestinal side effects and electrolyte disturbances were similar across the three groups. Split-dose preparations were associated with more significant sleep disturbances than single-dose PEG (P<0.001). Patients who received OSS reported more taste intolerance (P<0.01), while those who received single PEG reported more volume intolerance (P<0.001).

Split-dose OSS, split-dose PEG, and single-dose PEG regimens provide adequate and comparable bowel preparation for colonoscopy with good patient tolerance and no significant adverse effects. Overnight PEG and OSS preparations were associated with more substantial sleep disturbances. OSS is associated with more taste intolerance, while single PEG is associated with more volume intolerance.

The adenoma detection rate (ADR), recognized as a surrogate marker for colorectal cancer (CRC) incidence and mortality reduction, is closely linked to the efficacy of bowel cleansing. However, there is a dearth of evidence examining the impact on ADR when using 2 distinct very-low-dose bowel cleansing products. This study sought to compare ADR in an immunochemical fecal occult blood test (iFOBT)-based organized screening program by using 1 L of polyethylene glycol plus ascorbate (1L-PEGA) versus sodium picosulfate with magnesium citrate (SPMC), both administered in a split-dose regimen.

We conducted a comparative, parallel, randomized, noninferiority, and low-intervention clinical trial targeting individuals from a population CRC screening program aged 50 to 69 years with a positive iFOBT result scheduled for a workup colonoscopy in the morning. Participants were randomized to either 1L-PEGA or SPMC for bowel cleansing. The main outcome was ADR, whereas secondary outcomes were bowel preparation quality, safety, tolerability, and satisfaction.

A total of 1002 subjects, 501 were included in each group. There were no differences between groups with respect to pooled ADR (SPMC, 56.5% [95% CI, 52.1-60.8]; 1L-PEGA, 53.7% [95% CI, 49.3-58.0]; relative risk, .95 [95% CI, .85-1.06]); therefore, SPMC demonstrated noninferiority in ADR compared with 1L-PEGA (difference, 2.8%; 2-sided 95% lower confidence limit, -3.4). In addition, there were no significant differences in mean lesions regardless of size and location between arms. Bowel preparation favored 1L-PEGA (96.2% vs 89.2%, P < .001), whereas SPMC exhibited significantly higher safety and tolerability, as shown by fewer nonserious treatment-emergent adverse events.

SPMC emerged as a noninferior laxative compared with 1L-PEGA concerning ADR. Despite the superior bowel preparation quality associated with 1L-PEGA, the safety, tolerability, and overall satisfaction of participants were higher with SPMC. (Clinical trial registration number: EudraCT: 2019-003186-18.).

Several randomized clinical trials comparing different bowel preparations (BP) have shown similar efficacy; however, there is a lack of real-world studies on this topic.

This study aims to identify the most effective BP regimen in a real-world setting and any predictors of inadequate BP.

A retrospective single-center study was conducted over 14 months at an academic hospital including outpatient colonoscopies in which adult patients did not teach on how to perform BP before colonoscopy. Colonoscopies with 1L-PEG, 2L-PEG and picosulphate mixtures were considered. A multivariable analysis for factors associated to poor BP was fitted.

Overall, 1779 patients (51 %F, 60±14) years were included. The 1L-PEG regimen provided a higher rate of BP adequacy at multivariate analysis (adjusted OR 2.30, 95 %CI 1.67-3.16,p < 0.001) and was associated with higher median Boston Bowel Preparation Scale score (p < 0.001), higher rate of right-colon cleansing (p < 0.001) and exam completion (p = 0.04). Furthermore, we identified male sex, history of constipation, active smoking, previous pelvic surgery, concomitant psychiatric/neurological or chronic kidney diseases as predictors of inadequate BP.

This is the largest real-world study comparing 1L-PEG to other BP regimens. Our results suggest 1L-PEG provides better BP in a non-controlled setting, improving clinical practice quality and minimizing the need for repeated colonoscopies and saving healthcare resources.

Polyethylene glycol (PEG) is considered the gold standard regimen for bowel preparation; however, due to the necessity of a large volume, patient tolerance is impaired. Therefore, lactulose is a novel alternative for colonoscopy preparation. This study aimed to investigate the efficacy and safety of lactulose-based bowel preparations in comparison with PEG for colonoscopy.

This is a prospective, non-blinded, comparative study. Outpatients were randomly divided into two groups: group 1 (111 patients), PEG; and group 2 (111 patients), lactulose. The following clinical outcomes were assessed in each group: degree of bowel clearance using the Boston bowel preparation score, colorectal polyp detection rate, adenoma detection rate, tolerability, and side effects.

The rate of inadequate bowel preparation was 8.1% and 1.8% for the PEG and lactulose groups, respectively (p=0.030). The Boston bowel preparation score for the entire colon was 7.34±1.17 and 8.36±1.09 for the PEG and lactulose groups, respectively (p<0.001). The satisfactory overall experience rates were 27.9% and 62.2% for the PEG and lactulose groups, respectively (p<0.001).

The novel bowel preparation with oral lactulose was superior to that with PEG in terms of colon cleansing, adenoma detection rate, tolerance, and patient experience.

An easy-to-use preparation-related model (PRM) predicting inadequate bowel preparation (BP) was developed and proved superior to traditional models in our previous study. Here we aimed to investigate whether PRM-based individualized intervention can improve BP adequacy.

Patients undergoing morning colonoscopy were prospectively enrolled in 5 endoscopic centers in China. After standard BP of split-dose polyethylene glycol (PEG) was completed, patients were randomized (1:1) to the individualized group or standard group. High-risk patients predicted by PRM score ≥3 were instructed to drink an additional 1.5 L PEG in the individualized group while not in standard group. The primary endpoint was the rate of adequate BP, defined by segmental Boston bowel preparation scale ≥2. Secondary outcomes included adenoma detection rate (ADR) and adverse events.

900 patients were randomly allocated to the individualized group (n = 449) and the control (n = 451). Baseline characteristics were similar between the two groups. The rates of high-risk patients were 19.6 % in individualized group and 19.7 % in standard group. In intention-to-treat analysis, adequate BP was 91.8 % in individualized group and 84.7 % in the standard group (p = 0.001). Among high-risk patients, adequate BP rate was 94.3 % in individualized group and 49.3 % in standard group (p < 0.001), and ADR were 40.9 % vs 16.9 %, respectively (p < 0.001). No significant differences were found regarding the adverse events and willingness to repeat BP (all p >0.05).

The individualized intervention using an additional dose of PEG to high-risk patients predicted by PRM, significantly improved BP quality. The intervention significantly improved ADR in high-risk patients. (ClinicalTrials.gov number: NCT04434625).

Adequate bowel cleansing is essential for colonoscopy quality. A novel 1 L polyethylene glycol plus ascorbate (1 L PEG+ASC) solution has been recently introduced. Nevertheless, the efficacy of 1 L PEG+ASC as compared to that of high-volume bowel preparation in both inpatients and outpatients is still unclear.

This single-blinded, non-inferiority study randomized patients undergoing colonoscopy to receive split-dose 1 L PEG+ASC or 4 L PEG. The primary endpoint was the overall cleansing success. Secondary endpoints were excellent cleansing and high-quality cleansing of the right colon, as well as lesions detection rate, patient compliance, tolerability and safety.

Overall, 478 patients were randomized to 1 L PEG+ASC (N = 236) or 4 L PEG (N = 242). The 1 L PEG+ASC showed higher cleansing success rate (91.8% vs 83.6%; P=0.01) and a high-quality cleansing of the right colon (52.3% and 38.5%; P=0.004) compared to 4 L PEG. Moreover, 1 L PEG+ASC achieved a higher cleansing success in out-patients (96.3%% vs 88.6%; P=0.018), and a similar success rate in the in-patients (84.7% vs 76.7%; P=0.18). Adenoma detection rate, tolerability and incidence of adverse events were comparable between preparations.

The 1 L PEG+ASC showed higher efficacy in achieving adequate colon cleansing compared with 4 L PEG, particularly in the right colon. No differences in the tolerability and safety were detected.

Methods that minimize the time for on-site bowel preparation before colonoscopy are needed. We prospectively validated that a novel algorithm-based active cleansing (ABAC) protocol could reduce the time for preparation compared with the conventional method.

This was an open-label, multicenter, prospective comparative study from April to October 2021. The study compared the bowel preparation time for colonoscopy between patients instructed with the ABAC protocol and control groups. Patients in the ABAC protocol group as well as the control group were administered 2000 mL of polyethylene glycol (PEG) within 2 hours. After the first two hours, patients in the protocol group voluntarily took 300 ml of the solution without the instruction of nursing staff depending on the number of defecations in the first 2 hours. The intervention and control groups were adjusted for background characteristics by propensity score matching (PSM).

After adjustment by PSM, 174 patients in each of the two groups were included in the final analysis. In the intention-to-treat analysis, the preparation time was significantly shorter in the intervention group than that in the control group (126.3 ± 32.7 min vs. 144.9 ± 39.9 min, P = 0.018). The proportion of additional PEG intake was significantly higher in the intervention group (16 [9.2%] vs. 6 [3.4%], P = 0.047). The number of defecations was also higher in the intervention group than in the control group (7.8 ± 2.5 vs. 6.3 ± 2.2, P = 0.001).

Simple active instruction protocol is effective to reduce on-site bowel preparation time and nursing staff labor for colonoscopy.

Whether body mass index (BMI) is a risk factor for poor bowel preparation is controversial, and the optimal bowel preparation regimen for people with a high BMI is unclear.

We prospectively included 710 individuals with high BMIs (≥ 24 kg/m2) who were scheduled to undergo colonoscopy from January to November 2021 at 7 hospitals. Participants were randomly allocated into 3 L split-dose polyethylene glycol (PEG) group (n=353) and 2 L PEG group (n=357). The primary outcome was the rate of adequate bowel preparation, and the secondary outcomes included Boston Bowel Preparation Scale (BBPS) score, polyp detection rate, cecal intubation rate, and adverse reactions during bowel preparation. Furthermore, we did exploratory subgroup analyses for adequate bowel preparation.

After enrollment, 15 individuals didn't undergo colonoscopy, finally 345 participants took 3 L split-dose PEG regimen, and 350 participants took 2 L PEG regimen for colonoscopic bowel preparation. 3 L split-dose PEG regimen was superior to 2 L PEG regimen in the rate of adequate bowel preparation (81.2% vs. 74.9%, P = 0.045), BBPS score (6.71±1.15 vs. 6.37±1.31, P < 0.001), and the rate of polyp detection (62.0% vs. 52.9%, P = 0.015). The cecal intubation rate was similar in both groups (99.7%). Regarding adverse reactions, individuals were more likely to feel nausea in the 3 L PEG group (30.9% vs. 19.3%; P = 0.001); however, the degree was mild. In the subgroup analysis for adequate bowel preparation, 3 L split-dose PEG regimen performed better than 2 L PEG regimen in the overweight (BMI 25-29.9 kg/m2 ) (P = 0.006) and individuals with constipation (P = 0.044), while no significant differences were observed in relatively normal (BMI 24-24.9 kg/m2) (P = 0.593) and obese individuals (BMI ≥ 30 kg/m2) (P = 0.715).

3 L split-dose PEG regimen is superior to 2 L PEG regimen for colonoscopic Bowel Preparation in relatively high-BMI individuals, especially overweight individuals (BMI 25-29.9 kg/m2 ).

This trial was registered in the Chinese Clinical Trials Registry (ChiCTR2000039068). The date of first registration, 15/10/2020, http://www.chictr.org.cn.

Surgical site infection (SSI) is a serious complication of intestinal surgery. In this meta-analysis, we aimed to explore the efficacy and safety of different preoperative oral antibiotic preparation (OABP) compared with intravenous antibiotic preparation (IVAP) and/or mechanical bowel preparation (MBP).

A meta-analysis consisting of adult patients adopting oral antibiotics versus other regimens during the preoperative preparation of elective intestinal surgery was performed. The outcome included overall SSI, organ space SSI, superficial SSI, deep SSI, and mortality rate.

A total of 35 randomized controlled trials (RCTs) consisting of 8445 adult patients were included in our present analysis. OABP regimens were combined with IVAP in 29 RCTs. In general, the incidence of overall SSI in the OABP group was less compared with the IVAP alone or IVAP+MBP group (RR 0.56, 95% CI 0.46-0.69, P < .00001, I2 = 47%). Metronidazoles plus quinolones or aminoglycosides showed the best effect on reducing the overall SSI. OABP in combination with preoperative and postoperative IVAP was both significantly associated with reduced SSI. IVAP before and within 24 h after surgery showed the best advantage. No difference was found between the OABP without IVAP group and the control group in reducing SSI. OABP regimens also demonstrated a lower incidence rate of organ space SSI, superficial SSI, deep SSI, and mortality.

OABP in combination with preoperative IVAP and within 24 h post-operation significantly reduced the incidence of SSI in intestinal surgery. Metronidazoles accompanied with quinolones or aminoglycosides might be the appropriate combinations for OABP regimens.

Proper bowel preparation is of paramount importance for enhancing adenoma detection rates and reducing postcolonoscopic colorectal cancer risk. Despite recommendations from gastroenterology societies regarding the optimal rates of successful bowel preparation, these guidelines are frequently unmet. Various approaches have been employed to enhance the rates of successful bowel preparation, yet the quality of cleansing remains suboptimal. Intensive bowel preparation techniques, supplementary administration of bowel solutions, and educational interventions aimed at improving patient adherence to instructions have been commonly utilized, particularly among patients at a high risk of inadequate bowel preparation. Expedited strategies conducted on the same day as the procedure have also been endorsed by scientific organizations. More recently, the utilization of artificial intelligence (AI) has emerged for the preprocedural detection of inadequate bowel preparation, holding the potential to guide the preparation process immediately preceding colonoscopy. This manuscript comprehensively reviews the current strategies employed to optimize bowel cleansing, with a specific focus on patients with elevated risks for inadequate bowel preparation. Additionally, the prospective role of AI in this context is thoroughly examined.

While a majority of outpatients may achieve cleanliness with standard cleansing protocols, dealing with hard-to-prepare patients remains a challenge. Rescue strategies based on AI are promising, but such evidence remains limited. To ensure proper bowel cleansing, a combination of strategies should be performed.

Bowel preparation is a crucial factor affecting the diagnostic accuracy of colonoscopy, and few randomized control trials evaluated enhancement in bowel preparation. In this study, we aimed to evaluate the effectiveness of walking exercises on bowel preparation before a colonoscopy procedure.

The present study is a single-blind randomized controlled trial involving 262 patients scheduled for colonoscopy procedures. These patients were randomly assigned to two groups: an intervention group (n = 131) and a control group (n = 131). In the intervention group, participants followed a predetermined plan that included the consumption of specific liquids and foods, bisacodyl pills, polyethylene glycol powder, and a regimen of walking exercises in preparation for their colonoscopy. Conversely, individuals in the control group followed the same regimen but were not instructed to engage in walking exercises. On the day of the colonoscopy, both groups were assessed for their level of physical activity using a foot counter. Additionally, an experienced gastroenterologist evaluated and compared the bowel preparation between the two groups using the Boston Bowel Preparation Scale (BBPS).

The number of footsteps recorded in the two groups exhibited a significant difference (P < 0.001). Although there was no statistically significant difference between the intervention and control groups in terms of mean BBPS scores (6.26 ± 1.9 vs. 6.29 ± 1.9, P = 0.416), individuals who took more than 6900 steps had significantly higher BBPS scores compared to those with fewer than 6900 footsteps (6.62 ± 1.8 vs. 5.92 ± 1.9, P = 0.003).In the univariate analysis, BBPS was found to be significantly associated with individuals under the age of 50 (OR: 2.45, 95% CI: 1.30-4.61, P = 0.006) and smoking status (OR: 0.41, 95% CI: 0.17-0.94, P = 0.043). In the multivariate analysis, the relationship between BBPS and age below 50 and smoking remained significant (OR: 2.50, 95% CI: 1.30-4.70, P = 0.005, and OR: 0.38, 95% CI: 0.16-0.93, P = 0.034, respectively).

A higher number of footsteps taken especially more than 6900 can significantly enhance bowel preparation; however, walking exercise as an intervention before colonoscopy is not significantly associated with BBPS. Also, older people and smokers seem to have fewer benefits from walking exercises for bowel preparation.

ISRCTN32724024 (Registration date:22/08/2018).

Based on published evidence and our expert experience, we provide recommendations to maximize the efficacy, safety, efficiency, and cost-effectiveness of routine colonoscopy. High-quality colonoscopy begins with colon preparation using a split or same-day dose and preferably a low-volume regimen for optimal patient tolerance and compliance. Successful cecal intubation can be achieved by choosing the correct colonoscope and using techniques to facilitate navigation through challenges such as severe angulations and redundant colons. Safety is a primary goal, and complications such as perforation and splenic rupture can be prevented by avoiding pushing through fixed resistance and avoiding loops in proximal colon. Furthermore, barotrauma can be avoided by converting to water filling only (no gas insufflation) in every patient with a narrowed, angulated sigmoid. Optimal polyp detection relies primarily on compulsive attention to inspection as manifested by adequate inspection time, vigorous probing of the spaces between haustral folds, washing and removing residual debris, and achieving full distention. Achieving minimum recommended adenoma detection rate thresholds (30% in men and 20% in women) is mandatory, and colonoscopists should aspire to adenoma detection rate approaching 50% in screening patients. Distal attachments can improve mucosal exposure and increase detection while shortening withdrawal times. Complete resection of polyps complements polyp detection in preventing colorectal cancer. Cold resection is the preferred method for all polyps < 10 mm. For effective cold resection, an adequate rim of normal tissue should be captured in the snare. Finally, cost-effective high-quality colonoscopy requires the procedure not be overused, as demonstrated by following updated United States Multi Society Task Force on Colorectal Cancer postpolypectomy surveillance recommendations.

Inpatients are more likely to have inadequate bowel preparation compared to outpatients. Although experts recommend 4L split polyethylene glycol (PEG) preparation, bowel preparation with castor oil (CaO) was recently found to reduce the volume of solution required. The aim of the study was to evaluate the cleansing effect and safety of 2L-PEG with Cao in bowel preparation among inpatients. Our study retrospectively analyzed the medical records and colonoscopy reports of inpatients (n = 1251) who underwent colonoscopy in the Affiliated Changzhou No.2 People Hospital of Nanjing Medical University, and the inpatients were divided into 2L-PEG-CaO and 4L-PEG group according to different bowel preparation protocols. Boston Bowel Preparation Scale (BBPS) is used to assess bowel preparation efficacy before colonoscopy. Furthermore, we also calculated other outcomes, such as polyp or adenoma detection rates and adverse events. A total of 1251 patients undergoing colonoscopy were included in this study, 738 were taken 4L-PEG and 513 2L-PEG-CaO. Both inpatients groups were matched for baseline characteristics. The 2L-PEG-CaO group was significantly higher than the 4L-PEG group on both BBPS (7.26 ± 1.75 vs 7.06 ± 1.58, P = .043) and adequate bowel cleansing rates (83.2% vs 77.4%, P = .011). Regarding adverse events, the 4L-PEG group was significantly higher than the 2L-PEG-CaO group on the incidence of abdominal fullness (6.4% vs 9.6%, P = .045) and adverse events (33.7% vs 28.5%, P = .048). The 2L split PEG with CaO preparation increased quality of bowel cleansing and improved tolerance in inpatients. Bowel preparation with 2L-PEG-CaO is suitable alternative to traditional 4L split PEG bowel preparation for colonoscopy of inpatients.

The single dose of 2 L polyethylene glycol (PEG) has shown high cleaning efficacy and tolerability in low-risk patients. However, the dosage of this regimen is still challenging for many patients. We investigated the efficacy and tolerability of a novel ultra-low-volume regimen using 1 L PEG and linaclotide (1 L PEG+L) versus a single dose of 2 L PEG in low-risk patients.

In this prospective, randomized, observer-blinded, multicenter study, low-risk adult patients scheduled for colonoscopy were enrolled and randomized (1:1) to receive the 1 L PEG+L regimen or the 2 L PEG regimen. The primary outcome was the effectiveness of bowel cleansing according to the Boston Bowel Preparation Scale. Secondary outcomes included cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate and adenoma detection rate, tolerability, adverse events, and willingness to repeat bowel preparation. The full analysis set (FAS) and per-protocol set (PPS) were used for statistical analyses.

A total of 548 patients comprised the FAS, and 522 patients comprised the PPS. Noninferiority on adequate bowel cleansing of 1 L PEG+L vs 2 L PEG was established both in FAS (90.5% vs 91.6%, P = .644) and PPS (90.3% vs 92.4%, P = .390). There were no significant differences regarding the total score and each segment scores of the Boston Bowel Preparation Scale, cecal intubation rate, cecal insertion time, withdrawal time, polyp detection rate, and adenoma detection rate (all, P > .05). However, patients in the 1 L PEG+L group reported less nausea (7.7% vs 17.1%, P < .01) and vomiting (4.0% vs 10.9%, P < .01) and had a higher willingness to repeat bowel preparation (95.2% vs 82.2%, P < .01).

The regimen of 1 L PEG+L was not inferior to 2 L PEG on colon cleansing, with better tolerability and higher willingness to repeat the bowel preparation in a low-risk population. (Clinical trial registration number: ChiCTR2100053273.).

Several risk factors affecting the adequacy of colon cleansing have been proposed during the last decades. However, less is known about the impact that atmospheric aspects could have on adequacy of the bowel cleansing. The study aimed to investigate if the atmospheric temperature could impact on the bowel cleansing during colonoscopy.

A prospective maintained database of the colonoscopies performed since 1st August 2017 to 31st March 2020 was retrospective reviewed. The primary outcome of the study was to identify if the atmospheric temperature was associated with inadequate colon cleansing during colonoscopy. Secondary outcome was to identify the other factors associated with an inadequate colon cleansing.

One thousand two hundred twenty patients were enrolled. High atmospheric temperature (> 25 °C) significantly influenced the colon cleansing (p < 0.0001). Adequate colon cleansing was negatively influenced by gender (female patients were associated with higher colon cleansing rate, p = 0.013), diabetes (p < 0.0001), previous pelvic surgery (p = 0.001), use of Beta-Blocker (p = 0.001), anti-platelet (p = 0.017), angiotensin converting enzyme inhibitors (p = 0.001), the adoption of 4 L Poly Ethylene Glycol solution (p = 0.009), single-dose regimen (p < 0.0001) low patients' compliance (p < 0.0001), higher age and body mass index (p < 0.0001 and p = 0.025), lower education levels (p < 0.0001). On the contrary, admission to the ward to perform bowel preparation positively impacted on colon cleansing (p = 0.002).

Atmospheric temperature could play an important role in the colon cleansing during colonoscopy, being high temperature (> 25 °C) associated with lower rate of adequate bowel cleansing. However, being this relationship never studied before, these results must be confirmed by other studies.

Colorectal cancer (CRC) is one of the most common cancers worldwide and its global incidence is rapidly increasing among adults younger than 50 years, especially in the 20-39 age group. Once a curative resection is achieved, surveillance is mandatory. Colonoscopy has a pivotal role aimed at resecting premalignant neoplasms and detecting cancer at a curable stage. In the current review, an update on the role of surveillance colonoscopy after CRC is provided, considered the most recent international guidelines and evidence published on this issue. In particular, several questions have been answered, why, how and how often colonoscopy should be performed, whether intensive surveillance is more effective than standard surveillance, how endoscopically resected T1 cancer should be followed, the different management existing between colon and rectal cancer, and, finally, how to improve the endoscopic surveillance. In a period of resource constraints, appropriateness will be mandatory, thus understanding how to optimize the role of colonoscopy in the surveillance of patients with a history of CRC is of crucial importance. Improving the quality of colonoscopy and identifying risk factors for recurrent and new-onset CRC, will allow us to individualize the surveillance program while sparing health care cost.

Screening-related colonoscopy is a vital component of screening initiatives to both diagnose and prevent colorectal cancer (CRC), with prevention being reliant upon early and accurate detection of pre-malignant lesions. Several strategies, techniques, and interventions exist to optimize endoscopists' adenoma detection rates (ADR).

This narrative review provides an overview of the importance of ADR and other colonoscopy quality indicators. It then summarizes the available evidence regarding the effectiveness of the following domains in terms of improving ADR: endoscopist factors, pre-procedural parameters, peri-procedural parameters, intra-procedural strategies and techniques, antispasmodics, distal attachment devices, enhanced colonoscopy technologies, enhanced optics, and artificial intelligence. These summaries are based on an electronic search of the databases Embase, PubMed, and Cochrane performed on 12 December 2022.

Given the prevalence and associated morbidity and mortality of CRC, the quality of screening-related colonoscopy quality is appropriately prioritized by patients, endoscopists, units, and payers alike. Endoscopists performing colonoscopy should be up to date regarding available strategies, techniques, and interventions to optimize their performance.

Data regarding bowel preparation in patients with Inflammatory Bowel Disease (IBD) are scarce.

To compare efficacy, safety, and tolerability of low-volume preparations in patients with IBD.

Single-center, randomized, prescriber, and colonoscopist-blinded clinical trial. IBD outpatients undergoing colonoscopy were randomized 1:1:1 to receive 1 Liter-polyethylene glycol-ascorbate (1L-PEG), 2 Liters-PEG, or sodium picosulfate (SP). The primary endpoint was percentage of quality cleansing assessed via the Boston Bowel Preparation Scale (BBPS ≥6, segments ≥2). Secondary endpoints were total high quality cleansing (BBPS 8 or 9), high-quality segmental BBPS (≥2), and patients' tolerability, symptoms, and satisfaction, assessed by questionnaires. Safety was monitored by adverse event reporting, laboratory evaluation at colonoscopy, and telephonic follow-up.

Ninety-two patients were included (33 1L-PEG, 28 2L-PEG, and 31 SP). No significant differences between preparations were observed in quality or high-quality total BBPS or high-quality segmental BBPS. Complete intake of the solution was higher for SP (p = 0.006) and lower for 1L-PEG (p = 0.02) compared to 2L-PEG intake (p = 0.55). Clinically irrelevant hyponatremia was higher in the SP group (p < 0.0001). SP instructions were easier to understand from patient's point of view (p = 0.01). Willingness to retake was higher with SP (p < 0.0001) and less for 1L-PEG (p < 0.0001). No serious adverse events were reported.

We observed no differences in efficacy between low-volume preparations in patients with IBD. Complete intake was higher for SP and lower for 1L-PEG. SP and 2L-PEG instructions were better understood and graded, and SP was more likely to be retaken. Willingness to retake was lower for 1L-PEG. No serious adverse events were reported.

No differences in terms of efficacy were regarded in this clinical trial comparing low-volume preparations for colonoscopy in patients with IBD: however, Sodium Pisoculfate is better tolerated and accepted from patient's point of view. No serious adverse events were reported.

The oral sulfate tablet (OST), commercially available as Orafang^® (Pharmbio Korea Co., Seoul, Korea) in Korea, is being used increasingly because of its bowel-cleansing efficacy, safety, and tolerability in adults undergoing colonoscopy. Other bowel cleansing agents, such as polyethylene glycol and sodium picosulfate/magnesium citrate, can cause plasma volume depletion and electrolyte disturbances, such as hyponatremia. On the other hand, the OST has never been reported to cause hyponatremia in Korea. To our knowledge, the authors experienced the first case of hyponatremic seizure in an 81-year-old woman to whom an OST was administered for bowel preparation before a colonoscopy. After ingesting the OST, she presented with seizure, confusion, and dyspnea. Upon arrival, her serum sodium level was 120 mEq/L, and the urine osmolality and sodium levels were 449 mOsm/kg and 253 mOsm/kg, respectively; chest imaging suggested pulmonary edema. The associated symptoms disappeared following treatment with an intravenous injection of normal saline and 3% NaCl to normalize the sodium level. This case shows that the OST can cause hyponatremia and other severe complications related to hyponatremia.

Colonoscopy is a fundamental tool in colorectal cancer (CRC) prevention. Nevertheless, one-fourth of colorectal neoplasms are still missed during colonoscopy, potentially being the main reason for post-colonoscopy colorectal cancer (PCCRC). Adenoma detection rate (ADR) is currently known as the best quality indicator correlating with PCCRC incidence.

We performed a literature review in order to summarize evidences investigating key factors affecting ADR: endoscopists education and training, patient management, endoscopic techniques, improved navigation (exposition defect), and enhanced lesions recognition (vision defect) were considered.

'Traditional' factors, such as split dose bowel preparation, adequate withdrawal time, and right colon second view, held a significant impact on ADR. Several devices and technologies have been developed to promote high-quality colonoscopy, however artificial intelligence may be considered the most promising tool for ADR improvement, provided that endoscopists education and recording are guaranteed.

Background and study aims  Clinical practice patterns for image-enhanced endoscopy (IEE) and colonic endoscopic resection practices vary among endoscopists. We conducted a survey to understand the differences in IEE and colonoscopic resection practices among endoscopists from India. Methods  An online cross-sectional survey comprising 40 questions regarding quality control of colonoscopy, IEE, and colonic endoscopic resection practices was circulated through the registry of the Indian Society of Gastroenterology and Association of Colon and Rectal Surgeons of India. Participation was voluntary and response to all questions was compulsory. Results  There were 205 respondents to the survey (93.2 % gastroenterologists, 90.2 % male, 54.6 % aged 30 to 40 years, 36.1 % working in academic institution, 36.1 % working in corporate hospitals). Of the endoscopists, 50.7 % had no training in IEE and 10.7 % performed endoscopy on systems without any IEE modalities. Endoscopists with more experience were more likely to use IEE modalities in practice routinely ( P  = 0.007). Twenty percent never used IEE to classify polyps. Sixty percent of respondents did not use dye-chromoendoscopy. Less experienced endoscopists used viscous solutions as submucosal injectate ( P  = 0.036) more often. Of the respondents, 44 % never tattooed the site of endoscopic resection. Ablation of edges post-endoscopic mucosal resection was not done by 25.5 % respondents. Most respondents used electronic chromoendoscopy (36.1 %) or random four-quadrant sampling (35.6 %) for surveillance in inflammatory bowel disease. Surveillance post-endoscopic resection was done arbitrarily by 24 % respondents at 6 months to 1 year. Conclusions  There are several lacunae in the practice of IEE and colonic endoscopic resection among endoscopists, with need for programs for privileging, credentialing and proctoring these endoscopic skills.

Delays in inpatient colonoscopy are commonly caused by inadequate bowel preparation and result in increased hospital length of stay (LOS) and healthcare costs. Low-volume bowel preparation (LV-BP; sodium sulfate, potassium sulfate, and magnesium sulfate ) has been shown to improve outpatient bowel preparation quality compared with standard high-volume bowel preparations (HV-BP; polyethylene glycol ). However, its efficacy in hospitalized patients has not been well-studied. We assessed the impact of LV-BP on time to colonoscopy, hospital LOS, and bowel preparation quality among inpatients.

We performed a propensity score-matched analysis of adult inpatients undergoing colonoscopy who received either LV-BP or HV-BP before colonoscopy at a quaternary academic medical center. Multivariate regression models with feature selection were developed to assess the association between LV-BP and study outcomes.

Among 1,807 inpatients included in this study, 293 and 1,514 patients received LV-BP and HV-BP, respectively. Among the propensity score-matched population, LV-BP was associated with a shorter time to colonoscopy (β: -0.43 [95% confidence interval: -0.56 to -0.30]) while having similar odds of adequate preparation (odds ratio: 1.02 [95% confidence interval: 0.71-1.46]; P = 0.92). LV-BP was also significantly associated with decreased hospital LOS among older patients (age ≥ 75 years), patients with chronic kidney disease, and patients who were hospitalized with gastrointestinal bleeding.

LV-BP is associated with decreased time to colonoscopy in hospitalized patients. Older inpatients, inpatients with chronic kidney disease, and inpatients with gastrointestinal bleeding may particularly benefit from LV-BP. Prospective studies are needed to further establish the role of LV-BP for inpatient colonoscopies.

Water exchange is superior to air insufflation in reducing discomfort and increasing adenoma detection during colonoscopy. However, prolonged cecal insertion time is a drawback. This study aims to investigate the factors affecting cecal insertion during water exchange colonoscopy.

We pooled data from five randomized clinical trials that included patients undergoing water exchange colonoscopy. Logistic analysis was performed to determine the independent factors associated with prolonged cecal insertion time (> 15 min).

The cohort included 912 patients (493 men and 419 women) with a median age of 57 years (interquartile range, 49-64 years). The median cecal insertion time was 13.5 min (interquartile range, 10.9-17.0 min). Multivariate logistic regression analysis indicated that female sex, body mass index < 25 kg/m² , a history of constipation, no sedation, less experienced endoscopist, Boston Bowel Preparation Scale score ≤ 6, infused water volume during insertion ≥ 1000 mL, and scope length at the cecum ≥ 85 cm were associated with prolonged cecal insertion time. With increasing volume of infused water (1000-2000 mL), the median cecal insertion time increased gradually from 11.4 to 23.0 min (P < 0.001).

The current study identified independent factors associated with prolonged cecal insertion time during water exchange colonoscopy. Several factors are modifiable to achieve a shorter insertion time, including better bowel preparation, the use of sedation, more experienced endoscopist, infusing less water during insertion, and maintaining a shorter scope length.

The quality of bowel preparation is an extremely important determinant of colonoscopy results. However, the efficacy of senna regimens in improving bowel cleanliness is uncertain. We conducted a systematic review and meta-analysis to synthesize data on whether using a senna bowel preparation regimen enhances the bowel cleanliness. We searched Web of Science Core Collection, MEDLINE, PubMed, Embase, Cochrane Library, and Scopus databases (from the inception to August 2021). The primary efficacy outcome was bowel cleanliness. Secondary outcomes included patient compliance, tolerance, and adverse events. Eleven trials fulfilled the inclusion criteria (3,343 patients. Overall, we found no significant differences in bowel cleanliness between the senna regimen and other bowel preparation regimens (odds ratio [95% confidence interval]: 1.02 [0.63, 1.67], p = 0.93). There was significant difference in tolerance (odds ratio [95% confidence interval]: 1.66 [1.08, 2.54], p = .02) and compliance (odds ratio [95% confidence interval]: 3.05 [1.42, 6.55], p = .004). The senna regimen yielded a significantly greater proportion of no nausea (odds ratio [95% confidence interval]: 1.84 [1.45, 2.32]) and vomiting (odds ratio [95% confidence interval]: 1.65 [0.81, 3.35]). Compared with other bowel preparation regimens, the senna regimen may be effective and safe in bowel cleaning before colonoscopy, with superior compliance and tolerance.

Water exchange (WE) improves lesion detection but misses polyps because of human limitations. Computer-aided detection (CADe) identifies additional polyps overlooked by the colonoscopist. Additional polyp detection rate (APDR) is the proportion of patients with at least 1 additional polyp detected by CADe. The number of false positives (because of feces and air bubble) per colonoscopy (FPPC) is a major CADe limitation, which might be reduced by salvage cleaning with WE. We compared the APDR and FPPC by CADe between videos of WE and air insufflation in the right-sided colon.

CADe used a convolutional neural network with transfer learning. We edited and coded withdrawal-phase videos in a randomized controlled trial that compared right-sided colon findings between air insufflation and WE. Two experienced blinded endoscopists analyzed the CADe-overlaid videos and identified additional polyps by consensus. An artifact triggered by CADe but not considered a polyp by the reviewers was defined as a false positive. The primary outcome was APDR.

Two hundred forty-five coded videos of colonoscopies inserted with WE (n = 123) and air insufflation (n = 122) methods were analyzed. The APDR in the WE group was significantly higher (37 [30.1%] vs 15 [12.3%], P = .001). The mean [standard deviation] FPPC related to feces (1.78 [1.67] vs 2.09 [2.09], P = .007) and bubbles (.53 [.89] vs 1.25 [2.45], P = .001) in the WE group were significantly lower.

CADe showed significantly higher APDR and lower number of FPPC related to feces and bubbles in the WE group. The results support the hypothesis that the strengths of CADe and WE complement the weaknesses of each other in optimizing polyp detection.

Adequate bowel cleansing is essential for high-quality colonoscopy. Recently, a new very low-volume 1 litre (1L) polyethylene glycol (PEG) plus ascorbate solution (ASC) has been introduced. Our aims were to assess the effectiveness and tolerability of this product compared to low-volume 2L PEG-ASC and high-volume 4L PEG solutions, in a real-life setting. In six endoscopy units in Sweden, outpatients undergoing colonoscopy were either prescribed solutions according to local routines, or the very low-volume solution in split dose regimen. Bowel cleansing effectiveness and patient experience was assessed using the Boston Bowel preparation scale (BBPS) and a patient questionnaire. A total of 1098 patients (mean age 58 years, 52% women) were included. All subsegment and the total BBPS scores were significantly greater for 1L PEG-ASC in comparison to other solutions (p < 0.05 for 1L PEG-ASC and 4L PEG for transverse and left colon, otherwise p < 0.001). Nausea was more frequent with 1L PEG-ASC compared to 2L PEG-ASC (p < 0.001) and vomiting were more often reported compared to both other solutions (p < 0.01 and p < 0.05 for 2L PEG-ASC and 4L PEG, respectively). Smell, taste, and total experience was better for 1L PEG-ASC compared to 4L PEG (p < 0.001), and similar compared to the 2L PEG-ASC. In conclusion, 1L PEG-ASC leads to better bowel cleansing compared to 2L PEG-ASC or 4L PEG products, with similar or greater patient satisfaction.

Oral sodium sulfate (OSS) solution and low-volume polyethylene glycol-based solutions are two of the more common low-volume purgatives used as colonoscopy preparations. Data on how these different low-volume solutions compare are mixed. Our aim was to conduct a meta-analysis of randomized controlled trials (RCTs) to compare OSS with low-volume polyethylene glycol solutions (PEG) plus ascorbic acid (PEG + Asc) solution with respect to (i) satisfactory bowel preparation, (ii) excellent bowel preparation, and (iii) tolerability.

Studies were identified by searching 10 medical databases for reports published from 1974 until 2019. Only fully published RCTs comparing OSS and low-volume PEG-based products with regard to overall satisfactory bowel preparation were included. Pooling was conducted by both fixed-effects and random effects models; results are presented from the random effects model when heterogeneity was significant.

Seven studies (involving 2049 subjects) met the inclusion criteria. There was no difference between OSS and PEG + Asc with respect to adequate bowel preparation (risk ratio [RR] 1.02 [0.99-1.06]; P = 0.16). OSS did result in a higher chance of excellent bowel preparation (RR 1.18 [1.06-1.31]; P = 0.03). OSS was associated with a 30% increased risk of nausea (RR 1.35 [1.03-1.77]; P = 0.03) and more than double the risk of vomiting (RR 2.30 [1.63-2.23]; P < 0.05) compared with PEG + Asc. Begg's funnel plot indicated low probability of publication bias.

Individuals at low risk of inadequate bowel preparation who use OSS for bowel preparation are more likely to achieve excellent bowel preparation, but are more likely to experience nausea and vomiting than are individuals using low-volume PEG-based solutions.