Magnetic endoscope imaging (ScopeGuide) elucidates the mechanism of action of the pain-alleviating impact of water exchange colonoscopy - attenuation of loop formation

JAG consensus statements for training and certification in colonoscopy

Introduction

In the UK, endoscopy certification is awarded when trainees attain minimum competency standards for independent practice. A national evidence-based review was undertaken to update and develop standards and recommendations for colonoscopy training and certification.

Methods

Under the oversight of the Joint Advisory Group (JAG), a modified Delphi process was conducted between 2019 and 2020 with multisociety expert representation. Following literature review and Grading of Recommendations, Assessment, Development and Evaluations appraisal, recommendation statements on colonoscopy training and certification were formulated and subjected to anonymous voting to obtain consensus. Accepted statements were peer reviewed by JAG and relevant stakeholders for incorporation into the updated colonoscopy certification pathway.

Results

In total, 45 recommendation statements were generated under the domains of: definition of competence (13), acquisition of competence (20), assessment of competence (8) and postcertification support (4). The consensus process led to revised criteria for colonoscopy certification, comprising: (1) achieving key performance indicators defined within British Society of Gastroenterology standards (ie, unassisted caecal intubation rate >90%, rectal retroversion >90%, polyp detection rate >15%+, polyp retrieval rate >90%, patient comfort <10% with moderate–severe discomfort); (2) minimum procedure count 280+; (3) performing 15+ procedures over the preceding 3 months; (4) attendance of the JAG Basic Skills in Colonoscopy course; (5) terminal ileal intubation rates of 60%+ in inflammatory bowel disease; (6) satisfying requirements for formative direct observation of procedure skills (DOPS) and direct observation of polypectomy skills (Size, Morphology, Site, Access (SMSA) level 2); (7) evidence of reflective practice as documented on the JAG Endoscopy Training System reflection tool; (8) successful performance in summative DOPS.

Conclusion

The UK standards for training and certification in colonoscopy have been updated, culminating in a single-stage certification process with emphasis on polypectomy competency (SMSA Level 2+). These standards are intended to support training, improve standards of colonoscopy and polypectomy, and provide support to the newly independent practitioner.

Minimal water exchange by the air-water valve versus left colon water exchange in unsedated colonoscopy: a randomized controlled trial

BACKGROUND

Water exchange colonoscopy is the least painful method for unsedated colonoscopies. Simplified left colon water exchange (LWE) reduces the cecal intubation time but it is difficult to avoid the use of an additional pump. Minimal water exchange (MWE) is an improved novel method that eliminates the need for pumps, but it is not clear whether MWE has the same efficiency as LWE.

METHODS

This was a prospective, randomized, controlled, noninferiority trial conducted in a tertiary hospital. Enrolled patients were randomized 1:1 to the LWE group or MWE group. The primary outcome was recalled insertion pain measured by a 4-point verbal rating scale. Secondary outcomes included adenoma detection rate (ADR), cecal intubation time, volume of water used, and patient willingness to repeat unsedated colonoscopy.

RESULTS

226 patients were included (LWE n = 113, MWE n = 113). The MWE method showed noninferior moderate/severe pain rates compared with the LWE method (10.6 % vs. 9.7 %), with a difference of 0.9 percentage points (99 % confidence interval [CI] -9.5 to 11.3; threshold, 15 %). ADR, cecal intubation time, and willingness to repeat unsedated colonoscopy were not significantly different between the two groups, but the mean volume of water used was significantly less with MWE than with LWE (163.7 mL vs. 407.2 mL; 99 %CI -298.28 to -188.69).

CONCLUSION

Compared with LWE, MWE demonstrated a noninferior outcome for insertion pain, and comparable cecal intubation time and ADR, but reduced the volume of water used and eliminated the need for a water pump.

Factors associated with prolonged cecal insertion time in patients undergoing water exchange colonoscopy

BACKGROUND AND AIM

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.

METHODS

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).

RESULTS

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).

CONCLUSIONS

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.

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.

Water-assisted colonoscopy: an international modified Delphi review on definitions and practice recommendations

BACKGROUND AND AIMS

Since 2008, a plethora of research studies has compared the efficacy of water-assisted (aided) colonoscopy (WAC) and underwater resection (UWR) of colorectal lesions with standard colonoscopy. We reviewed and graded the research evidence with potential clinical application. We conducted a modified Delphi consensus among experienced colonoscopists on definitions and practice of water immersion (WI), water exchange (WE), and UWR.

METHODS

Major databases were searched to obtain research reports that could potentially shape clinical practice related to WAC and UWR. Pertinent references were graded (Grading of Recommendations, Assessment, Development and Evaluation). Extracted data supporting evidence-based statements were tabulated and provided to respondents. We received responses from 55 (85% surveyed) experienced colonoscopists (37 experts and 18 nonexperts in WAC) from 16 countries in 3 rounds. Voting was conducted anonymously in the second and third round, with ≥80% agreement defined as consensus. We aimed to obtain consensus in all statements.

RESULTS

In the first and the second modified Delphi rounds, 20 proposed statements were decreased to 14 and then 11 statements. After the third round, the combined responses from all respondents depicted the consensus in 11 statements (S): definitions of WI (S1) and WE (S2), procedural features (S3-S5), impact on bowel cleanliness (S6), adenoma detection (S7), pain score (S8), and UWR (S9-S11).

CONCLUSIONS

The most important consensus statements are that WI and WE are not the same in implementation and outcomes. Because studies that could potentially shape clinical practice of WAC and UWR were chosen for review, this modified Delphi consensus supports recommendations for the use of WAC in clinical practice.

Magnetic endoscopic imaging as a rational investment for specific colonoscopies: a systematic review and meta-analysis

BACKGROUND

Magnetic endoscopic imaging (MEI) was regarded as an adjuvant device to improve procedural efficacy and patients' comfort during colonoscopy.

METHODS

Several electronic databases were searched to identify eligible studies. Based on the heterogeneity of included studies, random-effects or fixed-effects models were used to calculate pooled risk ratios (RR), risk difference (RD) or mean difference (MD) along with 95% confidence intervals (CIs).

RESULTS

Twenty-one randomized controlled trials (RCTs) were selected for meta-analysis, with a total of 7,060 patients. Although there is a slightly lower risk of cecal intubation failure with the adjuvant of MEI (RD 3%; P < 0.00001) compared to the control group, the updated studies show no significant benefits. Similarly, the cecal intubation time, pain scores, and loop formation with the adjuvant of MEI did not show any advantages. However, considerable significant benefits were found in the subgroup of technically difficult colonoscopy and inexperienced colonoscopists. Moreover, MEI was associated with lower loop intubation time, lower abdominal compression times, and better lesion localization.

CONCLUSION

The clinical benefits of MEI could be exaggerated. However, MEI has considerable advantages in technically difficult colonoscopies, the assistance for inexperienced colonoscopists, loop resolving, and lesion localization.

Diagnostic ileocolonoscopy: getting the basics right

Proficient colonoscopy technique that optimises patient comfort while simultaneously enhancing the timely detection of pathology and subsequent therapy is an aspirational and achievable goal for every endoscopist. This article aims to provide strategies to improve colonoscopy quality for both endoscopists and patients.

Feasibility of sedation on demand in Taiwan using water exchange and air insufflation: A randomized controlled trial

BACKGROUND AND AIM

Completion of colonoscopy without sedation eliminates sedation cost and complications. Reported in the United States and Europe, on-demand sedation is not routine practice in Taiwan. Water exchange (WE), characterized by infusion and nearly complete removal of infused water during insertion, reduces insertion pain compared to air insufflation (AI) during colonoscopy. We evaluated the feasibility of on-demand sedation in Taiwan. In a randomized controlled trial of WE vs AI colonoscopy, we also aimed to determine if WE augmented the implementation by reducing insertion pain and decreasing sedation requirement.

METHODS

This prospective patient-blinded study randomized patients to AI or WE (75 patients/group) to aid insertion. The primary outcome was the proportion of patients completing without sedation.

RESULTS

In the AI and WE groups, 76.0% and 93.3% (P = 0.006) completed without need for sedation, respectively. The WE group had lower insertion pain score (mean [SD]) (4.0 [2.9] vs 2.1 [2.6], P < 0.001), lower doses of propofol (25.7 [52.7] mg vs 9.1 [35.6] mg, P = 0.012), and less time in the recovery room (3.4 [7.4] vs 1.5 [5.5], P = 0.027) than the AI group. Patient satisfaction scores and willingness to repeat if needed in the future were similar.

CONCLUSION

On-demand sedation was feasible in Taiwan. The completion rate without sedation was high in patients (76.0% with standard AI) open to the option (no prior intent to receive the standard of full or minimal sedation). WE augmented the implementation by reducing insertion pain and decreasing sedation requirement without adversely affecting patient satisfaction or willingness to repeat.

Factors Associated With Adenoma Detection in Propofol-sedated Patients

GOALS

To assess the factors associated with adenoma detection in propofol-sedated patients.

BACKGROUNDS

Low adenoma detection rate (ADR) are linked to increased risk of interval cancer and related deaths. Compared with air insufflation (AI) colonoscopy, the method of water exchange (WE) significantly decreased insertion pain and increased ADR in unsedated patients. Deep sedation with propofol has been increasingly used in colonoscopy. One report suggested that WE significantly increased ADR in propofol-sedated patients, but the factors associated with adenoma detection were not analyzed.

STUDY

Post hoc multiple logistic regression analyses were performed based on pooled data from 2 randomized controlled trials to assess the factors associated with adenoma detection in propofol-sedated patients.

RESULTS

Propofol-sedated patients (n=510) were randomized to AI and WE. The baseline characteristics were comparable. Multiple logistic regression analyses show that age, withdrawal time, indications (screening vs. diagnostic), and WE were significantly and independently associated with higher ADR. WE had fewer patients with inadequate Boston Bowel Preparation Scale score of <6. Despite a significantly shorter inspection time, WE had significantly higher overall ADR than AI, especially in those with adequate Boston Bowel Preparation Scale of ≥6. Right colon ADR (17.5% vs. 10.5%), flat ADR (32.3% vs. 19.4%), combined advanced and sessile serrated ADR (13.1% vs. 7.4%) of WE were significantly higher than those of AI.

CONCLUSIONS

WE enhanced quality of colonoscopy in propofol-sedated patients by significantly improving colon cleanliness and overall ADR. Colonoscopists with patients under propofol sedation might consider evaluating WE method for performance improvement.

Comparison of Underwater vs Conventional Endoscopic Mucosal Resection of Intermediate-Size Colorectal Polyps

BACKGROUND & AIMS

Endoscopic mucosal resection (EMR) with submucosal injection is an established method for removing colorectal polyps, although the en bloc resection rate decreases when polyp size exceeds 10 mm. Piecemeal resection increases local recurrence. Underwater EMR (UEMR) is an effective technique for removal of sessile colorectal polyps and we investigated whether it is superior to conventional EMR (CEMR).

METHODS

We conducted a multicenter randomized controlled trial at 5 institutions in Japan. Patients with endoscopically diagnosed, intermediate-size (10-20 mm) sessile colorectal lesions were randomly assigned to undergo UEMR or CEMR. Only the most proximal lesion was registered. The UEMR procedure included immersion of the entire lumen in water and snare resection of the lesion without submucosal injection of normal saline. We analyzed outcomes of 108 colorectal lesions in the UEMR group and 102 lesions in the CEMR group. R0 resection was defined as en bloc resection with a histologically confirmed negative resection margin. The primary endpoint was the difference in the R0 resection rates between groups.

RESULTS

The proportions of R0 resections were 69% (95% confidence interval [CI] 59%-77%) in the UEMR group vs 50% (95% CI 40%-60%) in the CEMR group (P = .011). The proportions of en bloc resections were 89% (95% CI 81%-94%) in the UEMR group vs 75% (95% CI 65%-83%) in the CEMR group (P = .007). There was no significant difference in median procedure time (165 vs 175 seconds) or proportions of patients with adverse events (2.8% in the UEMR group vs 2.0% in the CEMR group).

CONCLUSIONS

In a multicenter randomized controlled trial, we found that UEMR significantly increased the proportions of R0 resections for 10- to 20-mm sessile colorectal lesions without increasing adverse events or procedure time. Use of this procedure should be encouraged. Trials registry number: UMIN000018989.

The advantages of water immersion colonoscopy in ambulatory service

BACKGROUND/AIMS

The purpose of this prospective study was to compare patients' discomfort during water immersion (WI) colonoscopy without sedation or available on request, with that of patients during air insufflation (AI) colonoscopy with sedation, in the ambulatory setting.

MATERIAL AND METHODS

A prospective observational study was conducted in 100 patients who performed a colonoscopy between August 2015 and February 2016 in an Ambulatory Gastroenterology Center in Cluj-Napoca, Romania. They were divided into two branches A and B. Patients in Group A underwent a classic colonoscopy with AI and standard sedation (2 mg of midazolam and 50 mg of tramadol), while patients in Group B underwent an unsedated or on demand sedation colonoscopy with WI technique.

RESULTS

The patients in group A presented a higher discomfort (statistically significant) compared to those in group B, and had also the median total discomfort score higher than those in group B. The patients in group A had also a higher discomfort score after examination. The total time of examination was the same in the two groups, but in group B the progression to cecum time was 3 minutes lower than for those in group A. A greater discomfort of the patient was correlated with the longer time required to reach the cecum.

CONCLUSION

In conclusion, WI colonoscopy is superior to AI technique in reducing insertion pain, progression-to-cecum time, minimizing sedation requirements and also in the willingness to repeat the technique.

A prospective RCT comparing combined chromoendoscopy with water exchange (CWE) vs water exchange (WE) vs air insufflation (AI) in adenoma detection in screening colonoscopy

Background

A low adenoma detection rate (ADR) increases risks of interval cancers (ICs). Proximal colon flat polyps, e.g. serrated lesions (SLs), are difficult to find. Missed proximal colon flat lesions likely contribute to IC.

Aims

We compared chromoendoscopy with water exchange (CWE), water exchange (WE) and air insufflation (AI) in detecting adenomas in screening colonoscopy.

Methods

After split-dose preparation, 480 veterans were randomized to AI, WE and CWE.

Results

Primary outcome of proximal ADR (55.6% vs 53.4% vs 52.2%, respectively) were similar in all groups. Adenoma per colonoscopy (APC) and adenoma per positive colonoscopy (APPC) were comparable. Detection rate of proximal colon SLs was significantly higher for CWE and WE than AI (26.3%, 23.6% and 11.3%, respectively, p = 0.002). Limitations: single operator; SLs only surrogate markers of but not IC.

Conclusions

When an endoscopist achieves high-quality AI examinations with overall ADR twice (61.6%) the recommended standard (30%), use of WE and CWE does not produce further improvement in proximal or overall ADR. Comparable APC and APPC confirm equivalent withdrawal inspection techniques. WE alone is sufficient to significantly improve detection of proximal SLs. The impact of increased detection of proximal SLs by WE on prevention of IC deserves to be studied. This study is registered at ClinicalTrial.gov (NCT#01607255).

Systematic review of safety and efficacy of therapeutic endoscopic-retrograde-cholangiopancreatography during pregnancy including studies of radiation-free therapeutic endoscopic-retrograde-cholangiopancreatography

AIM

To systematically review safety/efficacy of therapeutic endoscopic-retrograde-cholangiopancreatography (ERCP) performed during pregnancy, considering fetal viability, fetal teratogenicity, premature delivery, and future postpartum development of the infant.

METHODS

Systematic computerized literature search performed using PubMed with the key words “ERCP” and “pregnancy”. Two clinicians independently reviewed the literature, and decided on which articles to incorporate in this review based on consensus and preassigned priorities. Large clinical trials, meta-analyses, systematic reviews, and controlled trials were assigned higher priority than review articles or small clinical series, and individual case reports were assigned lowest priority. Dr. Cappell has formal training and considerable experience in conducting systematic reviews, with 4 published systematic reviews in peer-reviewed journals indexed in PubMed during the last 2 years, and with a PhD in neurophysiology that involved 5 years of training and research in biomedical statistics.

RESULTS

Advances in imaging modalities, including abdominal ultrasound, MRCP, and endoscopic ultrasound, have generally obviated the need for diagnostic ERCP in non-pregnant and pregnant patients. Clinical experience with performing ERCP during pregnancy is burgeoning, with > 500 cases of therapeutic ERCP reported in the literature, aside from a national registry study of 58 patients. These studies show that therapeutic ERCP has a very high rate of technical success in clearing the bile duct of gallstones, and has a relatively low and acceptable rate of maternal and fetal complications. The great majority of births after therapeutic ERCP are full-term, have normal birth weights, and are healthy. A recent trend is performing ERCP without radiation to eliminate radiation teratogenicity. Systematic literature review reveals 147 cases of ERCP without fluoroscopy in 8 clinical series. These studies demonstrate extremely high technical success in endoscopically removing choledocholithiasis, favorable maternal outcomes with rare maternal ERCP complications, and excellent fetal outcomes. ERCP without fluoroscopy generally confirms proper biliary cannulation by aspiration of yellow bile per sphincterotome or leakage of yellow bile around an inserted guide-wire.

CONCLUSION

This systematic literature review reveals ERCP is relatively safe and efficacious during pregnancy, with relatively favorable maternal and fetal outcomes after ERCP. Recommendations are provided about ERCP indications, special ERCP techniques during pregnancy, and prospects for future research.

Is water exchange superior to water immersion for colonoscopy? A systematic review and meta-analysis

Background/Aims

Recently, water exchange (WE) instead of water immersion (WI) for colonoscopy has been proposed to decrease pain and improve adenoma detection rate (ADR). This systematic review and meta-analysis is conducted to assess whether WE is superior to WI based on the published randomized controlled trials (RCTs).

Materials and Methods

We searched studies from PubMed, Cochrane Central Register of Controlled Trials, EMBASE, and MEDLINE. Only RCTs were eligible for our study. The pooled risk ratios (RRs), pooled mean difference (MD), and pooled 95% confidence intervals (CIs) were calculated by using the fixed-effects model or random-effects model based on heterogeneity.

Results

Five RCTs consisting of 2229 colonoscopies were included in this study. WE was associated with a significantly higher ADR than WI (RR = 1.18; CI = 1.05-1.32; P = 0.004), especially in right colon (RR = 1.31; CI = 1.07-1.61; P = 0.01). Compared with WI, WE was confirmed with lower pain score, higher Boston Bowel Preparation Scale score, but more infused water during insertion. There was no statistical difference between WE and WI in cecal intubation rate and the number of patients who had willingness to repeat the examination. Furthermore, both total procedure time and cecal intubation time in WE were significantly longer than that in WI (MD = 2.66; CI = 1.42-3.90; P < 0.0001; vs MD = 4.58; CI = 4.01-5.15; P < 0.0001).

Conclusions

This meta-analysis supports the hypothesis that WE is superior to WI in improving ADR, attenuating insertion pain and providing better bowel cleansing, but inferior in time and consumption of infused water consumption during insertion.

Difference in real-time magnetic image analysis of colonic looping patterns between males and females undergoing diagnostic colonoscopy

Background and study aim Magnetic imaging technology is of proven benefit to trainees in colonoscopy, but few studies have examined its benefits in experienced hands. There is evidence that colonoscopy is more difficult in women. We set out to investigate (i) associations between the looping configurations in the proximal and distal colon and (ii) differences in the looping prevalence between the sexes. We have examined their significance in terms of segmental intubation times and position changes required for the completion of colonoscopy.

Patients and methods We analyzed 103 consecutive synchronized luminal and magnetic image videos of diagnostic colonoscopies with normal anatomy undertaken by a single experienced operator.

Results Deep transverse loops and sigmoid N-loops were more common in females. A deep transverse loop was more likely to be present if a sigmoid alpha-loop or N-loop had formed previously. Patients with sigmoid N-loops were turned more frequently from left lateral to supine before the sigmoid-descending junction was reached, but there was no statistical correlation between completion time and looping pattern.

Conclusions This study has reexamined the prevalence of the common looping patterns encountered during colonoscopy and has identified differences between the sexes. This finding may offer an explanation as to why colonoscopy has been shown to be more difficult in females. Although a deep transverse loop following a resolved sigmoid alpha-loop was the most commonly encountered pattern, no statistical correlation between completion time and looping pattern could be shown. It is the first study to examine segmental completion times using a magnetic imager in expert hands.

Difficult colonoscopy: air, carbon dioxide, or water insufflation?

Background/Aims

This study aimed to compare tolerance to air, carbon dioxide, or water insufflation in patients with anticipated difficult colonoscopy (young, thin, obese individuals, and patients with prior abdominal surgery or irradiation).

Methods

Patients with body mass index (BMI) less than 18 kg/m² or more than 30 kg/m², or who had undergone previous abdominal or pelvic surgeries were randomized to air, carbon dioxide, or water insufflation during colonoscopy. The primary endpoint was cecal intubation with mild pain (less than 5 on visual analogue scale [VAS]), without use of sedation.

Results

The primary end point was achieved in 32.7%, 43.8%, and 84.9% of cases with air, carbon dioxide and water insufflation (P<0.001). The mean pain scores were 5.17, 4.72, and 3.93 on the VAS for air, carbon dioxide, and water insufflation (P<0.001). The cecal intubation rate or procedure time did not differ significantly between the 3 groups.

Conclusions

Water insufflation was superior to air or carbon dioxide for pain tolerance. This was seen in the subgroups with BMI <18 kg/m² and the post-surgical group, but not in the group with BMI >30 kg/m².

Cecal intubation rates in different eras of endoscopic technological development

Introduction

Colonoscopy plays a critical role in colorectal cancer (CRC) screening and has been widely regarded as the gold standard. Cecal intubation rate (CIR) is one of the well-defined quality indicators used to assess colonoscopy.

Aim

To assess the impact of new technologies on the quality of colonoscopy by assessing completion rates.

Material and methods

This was a dual-center study at the 2^nd Department of Surgery at Jagiellonian University Medical College and at the Specialist Center “Medicina” in Krakow, Poland. The CIR and cecal intubation time (CIT) in three different eras of technological advancement were determined. The study enrolled 27 463 patients who underwent colonoscopy as part of a national CRC screening program. The patients were divided into three groups: group I – 3408 patients examined between 2000 and 2003 (optical endoscopes); group II – 10 405 patients examined between 2004 and 2008 (standard electronic endoscopes); and group III – 13 650 patients examined between 2009 and 2014 (modern endoscopes).

Results

There were statistically significant differences in the CIR between successive eras. The CIR in group I (2000–2003) was 69.75%, in group II (2004–2008) was 92.32%, and in group III (2009–2014) was 95.17%. The mean CIT was significantly reduced in group III.

Conclusions

Our study shows that the technological innovation of novel endoscopy devices has a great influence on the effectiveness of the CRC screening program. The new era of endoscopic technological development has the potential to reduce examination-related patient discomfort, obviate the need for sedation and increase diagnostic yields.

Water Exchange Method Significantly Improves Adenoma Detection Rate: A Multicenter, Randomized Controlled Trial

OBJECTIVES

Adenoma detection rate (ADR) is a key colonoscopy quality indicator in Western clinical literature. Our low ADR prompted us to assess novel methods to improve performance. Western retrospective reports suggested that water exchange (WE) could increase ADR. However, most of these studies used pain score or intubation rate as the primary outcome. Here we test the hypothesis that WE significantly increases ADR among Chinese colonoscopists and design a prospective randomized controlled trial using ADR as our primary outcome.

METHODS

This prospective, randomized controlled trial was performed at six centers in China. Screening, surveillance, and diagnostic cases were randomized to be examined by WE or traditional air insufflation (AI) method. The primary outcome was ADR.

RESULTS

From April 2014 to July 2015, 3,303 patients were randomized to WE (n=1,653) and AI (n=1,650). The baseline characteristics were comparable. Overall ADR was 18.3% (WE) and 13.4% (AI) (relative risk 1.45, 95% confidential interval: 1.20-1.75, P<0.001). ADR in screening patients using AI was 25.8% (male) and 15.7% (female). ADR in screening patients aged >50 years old was 29.4% (WE) and 22.9% (AI) (relative risk 1.09, 95% confidential interval: 1.00-1.19, P=0.040). The increase by WE was reproducibly observed in all indication categories, and significant in screening and diagnostic cases. The limitation imposed by the unblinded investigators was mitigated by comparable inspection times in cases without polyps, similar adenoma per positive colonoscopy, and reproducible enhancement of ADR and adenoma per colonoscopy by WE across all eight investigators.

CONCLUSIONS

This prospective study confirms Western retrospective data that WE significantly improves ADR among Chinese colonoscopists. WE may be superior to AI for screening colonoscopy in China. Colonoscopists elsewhere with low ADR might consider evaluating WE for performance improvement.

Accuracy of preoperative tumor localization in large bowel using 3D magnetic endoscopic imaging: randomized clinical trial

Background

Laparoscopic surgery has become the standard treatment for colorectal cancer. A tumor that does not involve serosa is invisible intraoperatively, and manual palpation of the tumor during laparoscopy is not possible. Therefore, accurate localization of the neoplastic infiltrate remains one of the most important tasks prior to elective laparoscopic surgery. The aim of this study was to evaluate the utility of a magnetic endoscopic imaging (MEI) for precise preoperative endoscopic localization of neoplastic infiltrate within the large bowel.

Materials and methods

The study enrolled 246 patients who underwent elective surgery for colorectal cancer in 2012–2015 with accurate preoperative colonoscopic localization of the tumor. The analysis concerned patients with neoplastic infiltrate localized more than 30 cm from the anal verge. For evaluative purposes and accuracy of localization, the intestine was divided anatomically into 13 parts. Colonoscopic examinations were conducted with two types of endoscopes: group I—with MEI and group II—without MEI. Patients were assigned to the groups by random allocation. Ultimate confirmation of the tumor localization was accomplished by intraoperative evaluation.

Results

Group I involved 127 patients and group II 129. The two groups were compared in terms of age, sex, BMI and frequency of previous abdominal procedures. Proper localization of the lesion was confirmed in 95.23 % of group I patients and in 83.19 % of group II patients (p < 0.05). The greatest discrepancy in localization occurred in 8.9 % of patients from group I and 20 % of patients from group II in which the lesion was assessed primarily in the distal sigmoid.

Conclusions

A magnetic endoscopic imaging allows more accurate localization of neoplastic infiltrate within the large intestine compared to standard colonoscopy alone, especially within the sigmoid colon. This method can be particularly useful in planning and performing laparoscopic procedures to diminish the likelihood of improper bowel segment resection.

ClinicalTrials.gov number

NCT01688557

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-016-5203-4) contains supplementary material, which is available to authorized users.

Accuracy of polyp localization at colonoscopy

BACKGROUND AND STUDY AIMS

Accurate documentation of lesion localization at the time of colonoscopic polypectomy is important for future surveillance, management of complications such as delayed bleeding, and for guiding surgical resection. We aimed to assess the accuracy of endoscopic localization of polyps during colonoscopy and examine variables that may influence this accuracy.

PATIENTS AND METHODS

We conducted a prospective observational study in consecutive patients presenting for elective, outpatient colonoscopy. All procedures were performed by Australian certified colonoscopists. The endoscopic location of each polyp was reported by the colonoscopist at the time of resection and prospectively recorded. Magnetic endoscope imaging was used to determine polyp location, and colonoscopists were blinded to this image. Three experienced colonoscopists, blinded to the endoscopist's assessment of polyp location, independently scored the magnetic endoscope images to obtain a reference standard for polyp location (Cronbach alpha 0.98). The accuracy of colonoscopist polyp localization using this reference standard was assessed, and colonoscopist, procedural and patient variables affecting accuracy were evaluated.

RESULTS

A total of 155 patients were enrolled and 282 polyps were resected in 95 patients by 14 colonoscopists. The overall accuracy of polyp localization was 85 % (95 % confidence interval, CI; 60 - 96 %). Accuracy varied significantly (P < 0.001) by colonic segment: caecum 100 %, ascending 77 % (CI;65 - 90), transverse 84 % (CI;75 - 92), descending 56 % (CI;32 - 81), sigmoid 88 % (CI;79 - 97), rectum 96 % (CI;90 - 101). There were significant differences in accuracy between colonoscopists (P < 0.001), and colonoscopist experience was a significant independent predictor of accuracy (OR 3.5, P = 0.028) after adjustment for patient and procedural variables.

CONCLUSIONS

Accuracy of localization of polyps is imprecise and affected by position within the colon and colonoscopist, including their level of experience. Magnetic endoscope imaging may improve the localization of lesions during colonoscopy.

Water Exchange Is the Least Painful Colonoscope Insertion Technique and Increases Completion of Unsedated Colonoscopy

BACKGROUND & AIMS

Unsedated colonoscopy is acceptable for diagnostic, surveillance, and screening indications worldwide. However, insertion of the colonoscope can be painful; it is not clear which technique is least painful and thereby increases the likelihood of colonoscopy completion. We performed a head-to-head comparison of air insufflation (AI), carbon dioxide (CO2) insufflation, water immersion (WI), and water exchange (WE) to determine which combination of insertion techniques produces the least amount of pain.

METHODS

In a patient-blinded prospective trial, 624 subjects were assigned randomly to groups that underwent colonoscopy with AI-AI, CO2-CO2, WI-AI, WE-AI, WI-CO2, or WE-CO2 insertion and withdrawal techniques, including on-demand sedation, at the St. Barbara Hospital (Iglesias, Italy) or the Vìtkovice Hospital (Ostrava, Czech Republic), from October 2013 through June 2014. The primary outcome was real-time maximum insertion pain (0 = none, 10 = worst), recorded by an unblinded nurse assistant. At discharge, a blinded observer recorded the recalled maximum insertion pain and patients' and investigators' guesses about method or gas used.

RESULTS

Patients and investigators correctly guessed the method used for fewer than 44% of procedures, confirming adequate blinding. The correlation between real-time and recalled maximum insertion pain (r = 0.9; P < .0005) confirmed internal validation of the primary outcome. The WE group had the lowest scores: mean pain values were 5.2 for AI-AI (95% confidence interval [CI], 4.6-5.8), 4.9 for CO2-CO2 (95% CI, 4.3-5.4), 4.3 for WI-CO2 (95% CI, 3.8-4.9), 4.0 for WI-AI (95% CI, 3.5-4.5), 3.1 for WE-CO2 (95% CI, 2.7-3.4), and 3.1 for WE-AI (95% CI, 2.7-3.6) (P < .0005). The highest proportions of patients completing unsedated colonoscopy were in the WE groups. WE groups also had significantly better colon cleanliness, particularly in the transverse and right colon (P < .0005). One limitation of the study was that colonoscopists and assistants were not blinded to water-aided insertion methods.

CONCLUSIONS

In a prospective study of colonoscopy insertion methods, CO2 insufflation did not reduce real-time maximum insertion pain. Compared with AI or CO2, WI and WE reduced insertion pain. The least painful technique was WE, which significantly increased completion of unsedated colonoscopy and bowel cleanliness without prolonging insertion time. ClinicalTrials.gov number: NCT01954862.

Left-colon water exchange preserves the benefits of whole colon water exchange at reduced cecal intubation time conferring significant advantage in diagnostic colonoscopy - a prospective, randomized controlled trial

OBJECTIVES

Whole-colon water exchange (WWE) reduces insertion pain, increases cecal intubation success and adenoma detection rate, but requires longer insertion time, compared to air insufflation (AI) colonoscopy. We hypothesized that water exchange limited to the left colon (LWE) can speed up insertion with equivalent results.

METHODS

This prospective, randomized controlled study (NCT01735266) allocated patients (18-80 years) to WWE, LWE or AI group (1:1:1). The primary outcome was cecal intubation time.

RESULTS

Three hundred subjects were randomized to the WWE (n = 100), LWE (n = 100) or AI group (n = 100). Ninety-four to ninety-five per cent of patients underwent diagnostic colonoscopy. Baseline characteristics were balanced. The median insertion time was shorter in LWE group (4.8 min (95%CI: 3.2-6.2)) than those in WWE (7.5 min (95%CI: 6.0-10.3)) and AI (6.4 min (95%CI: 4.2-9.8)) (both p < 0.001) groups. The cecal intubation rates in unsedated patients of the two water exchange methods (WWE 99%, LWE 99%) were significantly higher than that (89.8%) in AI group (p = 0.01). The final success rates were comparable among the three groups after sedation was given. Maximum pain scores and number of patients needing abdominal compression between WWE and LWE groups were comparable, both lower than those in AI group (p < 0.05). No significant difference was observed regarding PDR, although the PDR in right colon tended to be higher in WWE group.

CONCLUSION

By preserving the benefits of WWE and reducing insertion time, LWE is appropriate for diagnostic colonoscopy, especially in settings with tight scheduling of patients. The higher PDR in the right colon in WWE group deserves to be further investigated.

A patient-blinded randomized, controlled trial comparing air insufflation, water immersion, and water exchange during minimally sedated colonoscopy

OBJECTIVES

Minimal sedation obviates patient recovery burdens, but intolerable pain limits success of cecal intubation. Painless or minimally uncomfortable insertion ensures success of cecal intubation, current patient satisfaction, and willingness to repeat future colonoscopy with minimal sedation. Water immersion (WI) and water exchange (WE), when separately compared with air insufflation (AI), significantly reduced insertion pain. To assess comparative effectiveness, we conducted a randomized controlled trial with head-to-head comparison of these three methods. We hypothesized that WE could produce the highest proportion of patients reporting painless insertion.

METHODS

This prospective patient-blinded trial (NCT01535326) enrolled minimally sedated (25 mg intramuscular meperidine) patients randomized to AI, WI, or WE (90 patients/group) to aid insertion. The previously validated primary outcome was the proportion of patients reporting painless insertion.

RESULTS

Painless insertion was reported by 30.0% (AI), 43.3% (WI), and 61.1% (WE) of patients (P<0.001). Multivariate logistic regression analysis revealed that, after adjusting for gender, body mass index, abdominal compression, position change, insertion time to cecum, and length of scope at cecum, only WE was significantly associated with painless insertion compared with AI (odds ratio (OR)=0.08, 95% confidence interval (CI)=0.03-0.24, P<0.001) or WI (OR=0.14, 95% CI=0.05-0.40, P<0.001). Adenoma detection rate (ADR) in the right (cecum and ascending) colon was 11.1% (AI), 14.4% (WI), and 26.7% (WE) (P=0.015). The limitations included single site study with unblinded colonoscopist and assistant.

CONCLUSIONS

This head-to-head comparison of AI vs. WI vs. WE confirmed that WE was superior to WI and AI, with a significantly greater proportion of patients reporting painless insertion. The significantly higher ADR in the right colon in the WE group warrants further investigations.

Magnetic endoscopic imaging during colonoscopy is associated with less pain and decreased need of analgesia and sedation--results from a randomized controlled trial

OBJECTIVE

Colonoscopy is the method of choice for examining patients with lower gastrointestinal symptoms. The procedure is, however, in many cases, associated with pain and impaired compliance. Magnetic endoscopic imaging (MEI) generates a three-dimensional image of the colonoscope on a computer screen which may enable the colonoscopist to avoid looping, and consequently improve patient satisfaction.

MATERIAL AND METHODS

In this randomized controlled trial, 200 outpatients referred to colonoscopy at Østfold Hospital Trust, Fredrikstad, Norway, were included. Patients were randomized to either the standard arm (using fluoroscopy on demand, n = 100), or the MEI arm (n = 100). End points were time to cecum, subjective pain experiences, and use of sedation or analgesics.

RESULTS

Out of a total of 200 patients, 54% were men. However, no significant differences between the groups according to gender were found. Fluoroscopy was applied in 23% of the cases in the standard group. Use of MEI was associated with decreased time to cecum (p < 0.05), decreased pain scores (Visual Analogue Scale, p < 0.05), decreased need of analgesia (p < 0.01), and decreased amount of administered midazolam and pethidin (p < 0.05 in both).

CONCLUSIONS

MEI during colonoscopy was associated with decreased pain and less on-demand requests for sedation and analgesia. In addition, the use of MEI reduced the cecal intubation time. Consequently the implementation of magnetic endoscopic imaging in the endoscopy suits may be beneficial, particularly in the clinically difficult cases.