Safety and Efficacy of a Same-Day Low-Volume 1 L PEG Bowel Preparation in Colonoscopy for the Elderly People and People with Renal Dysfunction

Efficacy of Two Kinds of Scissor-Type Knives for Colorectal Endoscopic Submucosal Dissection: A Retrospective Comparative Study

INTRODUCTION

Scissor-type knives are spreading as safe devises in endoscopic submucosal dissection (ESD). We evaluated the efficacy of two kinds of scissor-type knives (Clutch Cutter: CC, Fujifilm Co. and SB Knife Jr2: SB, SB-KAWASUMI Laboratories. Inc.) in colorectal ESD.

METHODS

This single-center retrospective study analyzed 178 ESD cases treated with CC from January 2020 to August 2021 and 91 cases with SB from September 2021 to December 2023. The two groups were compared through propensity score matching. Therapeutic results, such as ESD procedure time, en bloc resection rate, perioperative bleeding frequency, and complications, were analyzed in each group. Risk factors for long ESD procedure time (≥ 90 min) were also examined.

RESULTS

After matching, 87 cases in each group were analyzed. There was no significant difference in the ESD procedure time (min, median [interquartile range]) between the CC and SB groups (54.0 [36.0-72.0] vs. 53.0 [39.0-72.0], p = 0.99). Additionally, there were no differences in the en bloc resection (100% vs. 100%, p = 1.00), perioperative perforation (1.1% vs. 1.1%, p = 1.00), or delayed bleeding (1.1% vs. 0.0%, p = 1.00). There was a significant difference in perioperative bleeding frequency (mean ± standard deviation: 1.8 ± 2.6 vs. 3.0 ± 3.5, p < 0.01). The significant risk factors (odds ratio [95% confidence interval]) for long ESD procedure time in patients treated with CC or SB were antiplatelet (7.51 [1.82-31.00]), large lesion size (1.08 [1.05-1.12]), severe fibrosis (24.30 [7.60-77.90]), and perioperative bleeding frequency (1.34 [1.14-1.56]).

CONCLUSIONS

CC and SB in colorectal ESD enabled high en bloc resection and low complication rates. CC showed significantly less perioperative bleeding than SB.

Efficacy of Polyethylene Glycol Electrolyte Powder Combined With Linaclotide for Colon Cleansing in Patients With Chronic Constipation Undergoing Colonoscopy: A Multicenter, Single-Blinded, Randomized Controlled Trial

INTRODUCTION

Constipation is an independent risk factor for poor bowel preparation. This study aimed to evaluate the bowel cleansing efficacy and safety of polyethylene glycol (PEG) combined with linaclotide (lin) for colonoscopy in patients with chronic constipation (CC).

METHODS

This single-blinded, randomized, controlled, and multicenter study was conducted from July 2021 to December 2022 at 7 hospitals. Patients with CC who underwent colonoscopies were enrolled and randomly assigned to 4 groups with split-PEG regimens: 4L-PEG group, 4L-PEG+1d-Lin group, 3L-PEG+1d-Lin group, and 3L-PEG+3d-Lin group. The primary outcome was rates of adequate bowel preparation, defined as a total BBPS score ≥6 and a score ≥2 for each segment. Secondary outcomes were adverse effects, sleep quality, willingness to repeat the colonoscopy, adenoma detection rate, and polyp detection rate.

RESULTS

Five hundred two patients were enrolled. The rates of adequate bowel preparation (80.0% vs 60.3%, P < 0.001; 84.4% vs 60.3%, P < 0.001) and the total Boston Bowel Preparation Scale (BBPS) scores (6.90 ± 1.28 vs 6.00 ± 1.61, P < 0.001; 7.03 ± 1.24 vs 6.00 ± 1.61, P < 0.01) in the 4L-PEG+1d-Lin group and the 3L-PEG+3d-Lin group were superior to that in the 4L-PEG group. Compared with the 4L-PEG group, the 4L-PEG+1d-Lin group (66.7% vs 81.7%, P = 0.008) and the 3L-PEG+3d-Lin group (75.0% vs 81.7%, P = 0.224) had a lower percentage of mild adverse events. No statistically significant difference in willingness to repeat the colonoscopy, sleep quality, polyp detection rate, or adenoma detection rate was observed among groups.

DISCUSSION

PEG combined with linaclotide might be an effective method for bowel preparation before colonoscopy in patients with CC.

Additional 30-Second Observation of the Right-Sided Colon for Missed Polyp Detection With Texture and Color Enhancement Imaging Compared with Narrow Band Imaging: A Randomized Trial

INTRODUCTION

The efficacy of texture and color enhancement imaging (TXI) in the novel light-emitting diode endoscopic system for polyp detection has not been examined. We aimed to evaluate the noninferiority of the additional 30-second (Add-30-s) observation of the right-sided colon (cecum/ascending colon) with TXI compared with narrow band imaging (NBI) for detecting missed polyps.

METHODS

We enrolled 381 patients ≥40 years old who underwent colonoscopy from September 2021 to June 2022 in 3 institutions and randomly assigned them to either the TXI or NBI groups. The right-sided colon was first observed with white light imaging in both groups. Second, after reinsertion from hepatic flexure to the cecum, the right-sided colon was observed with Add-30-s observation of either TXI or NBI. The primary endpoint was to examine the noninferiority of TXI to NBI using the mean number of adenomas and sessile serrated lesions per patient. The secondary ones were to examine adenoma detection rate, adenoma and sessile serrated lesions detection rates, and polyp detection rates in both groups.

RESULTS

The TXI and NBI groups consisted of 177 and 181 patients, respectively, and the noninferiorities of the mean number of adenomas and sessile serrated lesions per patients in the second observation were significant (TXI 0.29 [51/177] vs NBI 0.30 [54/181], P < 0.01). The change in adenoma detection rate, adenoma and sessile serrated lesions detection rate, and polyp detection rate for the right-sided colon between the TXI and NBI groups were not different (10.2%/10.5% [ P = 0.81], 13.0%/12.7% [ P = 0.71], and 15.3%/13.8% [ P = 0.71]), respectively.

DISCUSSION

Regarding Add-30-s observation of the right-sided colon, TXI was noninferior to NBI.

Adherence and Effectiveness of MoviPrepⓇ in Bowel Preparation for Colonoscopy: A Multicenter Study from the Hiroshima GI Endoscopy Research Group

Objectives

Bowel preparation is burdensome because of long cleansing times and large dose volumes of conventional polyethylene glycol (PEG) lavage solution NiflecⓇ (Nif). MoviPrep (Mov)Ⓡ is a hyperosmolar preparation of PEG, electrolytes, and ascorbic acid; despite the smaller dose volume of 2 L, it can be challenging for many patients. We examined a more effective and acceptable bowel preparation method without compromising cleanliness and effectiveness, combining low-residue diet and laxative (Modified Brown Method) in Mov administered 1 day pre-colonoscopy.

Methods

This multicenter, randomized, open-label, parallel-group comparative study, conducted at Hiroshima University Hospital and 7 affiliated hospitals in May 2015-March 2016, evaluated adherence to and effectiveness of Mov in bowel preparation. Participants (n=380) were allocated to receive 1 of 3 pre-colonoscopy regimens: Nif+Modified Brown Method (Group A), Mov+Modified Brown Method (Group B), or Mov+Laxative (Group C).

Results

Total intake volume showed no significant difference among the groups. Bowel preparation time was significantly shorter in Group B (112.4±44.8 min, n=118) than in Groups A (131.3±59 min, n=105) and C (122.6±48.1 min, n=115). Sleep disturbance (37%) was significantly higher in Group B than Group A; distension (11%) was significantly lower in Group C than in Groups A and B (p<0.05, respectively). No severe adverse events occurred in any group.

Conclusions

Mov+Modified Brown method provided significantly shorter bowel preparation time, with no significant difference in total intake volume among the regimens. Mov+Laxative yielded significantly less distension than the other groups, with bowel preparation equivalent to that of the Nif+Modified Brown method.

Colon Bowel Preparation in the Era of Artificial Intelligence: Is There Potential for Enhancing Colon Bowel Cleansing?

BACKGROUND AND OBJECTIVES

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.

CONCLUSIONS

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.

The Efficacy of 480 ml Oral Sodium Sulfate for Improving Insufficient Bowel Preparation of Colonoscopy with High-Concentrated Polyethylene Glycol

Objectives

Oral sulfate solution (OSS) is used for bowel preparation (BP) during colonoscopy. The way of taking this agent can be used a same-day regimen (only on the day of colonoscopy) and split regimen (the day before and on the day of colonoscopy) for receiving it. In this study, we analyzed the efficacy of a same-day regimen of 480 ml OSS for insufficient bowel preparation (BP) with high-concentrated polyethylene glycol (H-PEG).

Materials and Methods

This multicenter retrospective study was conducted from December 2021 to December 2022 at three related institutions on patients aged ≥ 20 years with a fair or poor Aronchick score of BP with 1 l H-PEG in previous colonoscopy. All patients received a low-residual diet and 10 ml of 0.75% picosulfate sodium a day before the colonoscopy and 480 ml of OSS and ≥1 l of water 3 hours before the colonoscopy. We analyzed the rate of improvement with OSS compared to H-PEG and other efficacies, and adverse events (AE).

Results

We evaluated 125 cases (77 males) with an average age of 72.1 ± 8.8 years. The completion rate of 480 ml of OSS was 97.6% (122/125). The improvement rate of BP showing good or excellent score with OSS was 70.4% (88/125). Compared OSS with previous H-PEG, the insertion time (min) was 7.0 ± 4.8 vs. 8.1 ± 6.0 (p = 0.01), and the adenoma detection rates were 67.2% vs. 63.2% (p = 0.05). The cleansing time (min) was 131 ± 46 vs. 165 ± 53 (p < 0.01). The rate of AE with OSS was 10.4% (13/125). There were no significant differences about AE in age and gender. The tolerance of OSS compared with H-PEG (good/similar/bad) was 72.0%/24.8%/3.2% (amounts), 26.4%/39.2%/34.4% (taste), and 76.8%/10.4%/12.8% (overall preference), respectively.

Conclusions

The same-day regimen of 480 ml OSS effectively improved the insufficient BP of 1 l H-PEG.

Visualization analysis of research on pre-colonoscopy bowel preparation

BACKGROUND

Bowel preparation is an essential step before colonoscopy, and its research topics are relatively scattered. Understanding the research status and development trend of bowel preparation is of great value for disease research and actual clinical work. However, there is currently a lack of research in this field in the form of bibliometrics.

AIM

To understand the research hotspots and development trends of bowel preparation during colonoscopy around the world.

METHODS

The literature about the topics of bowel preparation was retrieved from the CNKI, Wanfang, VIP, China Biomedical Literature Database (CBM), and Web of Science core datasets from the inception of the database to September 10, 2022. CiteSpace 6.1. R3 was used to visually analyze the annual number of publications, countries, institutions, authors, keywords, clusters, and co-citation literature.

RESULTS

A total of 2340 Chinese and 2574 English publications were included, and the number of annual publications showed an increasing trend from year to year. The author with the largest number of publications worldwide was Hassan Cesare, and the most productive countries included USA, Korea, UK, Italy, and China. Meng Xiao-Fen, Zhang Yuan-Yuan, and Niu Mei-E were the China's most prolific authors. The First Affiliated Hospital of Suzhou University, the General Hospital of the Chinese People's Liberation Army, and the Second Affiliated Hospital of Xi'an University were the most prolific institutions. Research hotspots focused on the quality of bowel preparation, the design of bowel preparation programs, and special groups for bowel preparation.

CONCLUSION

Studies related to bowel preparation have certain foundations, and China's research can follow international hotspots, but cooperation among countries still needs to be strengthened. We should expand the research output related to bowel preparation based on a broader population and more suitable for the development of the era of big data, to provide higher quality research evidence for clinical practice.

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

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

Analysis of Texture and Color Enhancement Imaging for Improving the Visibility of Non-polypoid Colorectal Lesions

INTRODUCTION

An endoscopic system using 5-color light-emitting diodes (LEDs) (EVIS X1; Olympus Co., Tokyo, Japan), which includes texture and color enhancement imaging (TXI), has been released. In this study, we analyzed the effects of TXI on the visibility of non-polypoid colorectal lesions and its diagnostic accuracy.

METHODS

We reviewed 101 non-polypoid lesions from 26 patients observed with white light imaging (WLI), narrow band imaging (NBI), and TXI. One representative image of each mode was evaluated by 6 endoscopists using a polyp visibility score of 4 (excellent) to 1 (poor). We calculated the color difference (CD) values for each lesion in the three modes. For tumor characteristics, one representative image of TXI and NBI magnification was evaluated by 3 experts according to a NBI classification.

RESULTS

The least squares means [95% confidence interval] of polyp visibility score of TXI (3.42 [3.06-3.77]) was significantly higher than that of WLI (2.85 [2.49-3.20], p < 0.001) but not that of NBI (3.33 [2.98-3.69], p = 0.258). The CD value of TXI (13.3 ± 6.3) was higher than that of WLI (9.7 ± 6.0, p < 0.001) but not that of NBI (13.1 ± 6.8, p = 0.81). For sessile serrated lesions, the CD value of TXI (11.1 ± 4.4) tended to be lower than that of NBI (12.6 ± 6.0, p = 0.07). The diagnostic accuracy and confidence level of magnification for NBI were significantly better than those for TXI (87.1 vs. 80.5%, p = 0.027, 87.5 vs. 62.7%, p < 0.001, respectively).

CONCLUSION

TXI showed better visibility than WLI in terms of the endoscopist's score and CD value and may improve polyp detection.

Comparison of Two Types of 1-L Polyethylene Glycol-ascorbic Acid as Colonoscopic Bowel Preparation: A Prospective Randomized Study

BACKGROUND/AIMS

Recently, 1-L polyethylene glycol-ascorbic acid (PEG-Asc) has been used to reduce the volume of preparation agents in colonoscopy. This clinical trial aimed to compare the efficacy and safety of two types of 1-L PEG-Asc (CleanViewAL^® [Tae Joon Pharmaceutical Company, Seoul, Korea] and Plenvu^® [Norgine, Harefield, United Kingdom]) in average-aged adults.

METHODS

This study was a prospective, randomized, non-inferiority, open-label, phase 4 clinical trial. The primary endpoint was the efficacy evaluated using the Boston bowel preparation scale (BBPS), and the secondary endpoint was clinical safety.

RESULTS

In total, 173 patients were assigned to either the CleanViewAL^® (n=84) or Plenvu^® (n=89) group. Overall cleansing successes of 97.6% (82/84) and 98.8% (88/89) were achieved in the CleanViewAL^® group and in the Plenvu^® group, respectively, showing that CleanViewAL^® has similar bowel cleansing efficacy to Plenvu^® (95% CI, -0.052 to 0.027; p=0.207). The total BBPS score was 8.67±1.00 and 8.70±0.76 in the CleanViewAL^® group and Plenvu^® group, respectively (p=0.869). The most common adverse symptom was nausea, and no adverse symptoms requiring hospitalization were reported in either group. There were no cases of critical hypernatremia and liver dysfunction exceeding the common terminology criteria for adverse events grade I. An overall satisfaction score (scale of 1 to 10) showed no difference between the two groups (p=0.289). However, the CleanViewAL^® group showed a higher taste satisfaction score (scale of 1 to 5) than the Plenvu^® group (CleanViewAL^®: 2.90±0.91, Plenvu^®: 2.60±0.86, p=0.028).

CONCLUSIONS

Both types of 1-L PEG-Asc, CleanViewAL^® and Plenvu^®, are effective and safe bowel cleansing agents in average-aged adults. CleanViewAL^® was preferred in terms of taste satisfaction.

Electrolyte disturbances after bowel preparation for colonoscopy: Systematic review and meta-analysis

BACKGROUND AND STUDY AIMS

We conducted a systematic review and meta-analysis of population-based studies to explore pooled prevalence and magnitude of electrolyte changes after bowel preparation for colonoscopy based on the most recent guidelines.

PATIENTS AND METHODS

PubMed and Cochrane were queried for population-based studies examining changes in electrolyte values after bowel preparation, published by July 1, 2021. We report prevalences of serum hypokalemia, hyponatremia, hyperphosphatemia, and hypocalcemia after bowel preparation and changes in mean electrolyte values after vs. before bowel preparation using sodium phosphate (NaP) and polyethylene glycol (PEG).

RESULTS

Thirteen studies met the inclusion criteria; 2386 unique patients were included. Overall, hypokalemia was found in 17.2% (95% CI 6.7, 30.9) in the NaP group vs. 4.8% (95% CI 0.27, 13.02) in the PEG group. The magnitude of potassium decrease after NaP bowel preparation was significantly increased compared to PEG (mean difference -0.38; 95% CI -0.49 to -0.27, P < 0.001). No study reported on major complications.

CONCLUSIONS

Hypokalemia was found in 17.2% of patients after bowel preparation with NaP and in 4.8% of patients with PEG, a finding that is clinically relevant with respect to choosing the type of bowel preparation. The magnitude of the potassium decrease after NaP was significantly higher compared to PEG. These data provide the evidence that supports the recommendation of the European Society of Gastrointestinal Endoscopy against routine use of NaP for bowel preparation.

Risk Factors of Delayed Bleeding After Cold Snare Polypectomy for Colorectal Polyps: A Multicenter Study

BACKGROUND

Delayed bleeding (DB) rarely occurs after cold snare polypectomy (CSP) for colorectal polyps, but no large-scale studies have investigated this. The present study evaluated the rate, characteristics, and risk factors of DB of CSP.

METHODS

We conducted a multicenter retrospective study at 10 Japanese institutions. A total of 18,007 patients underwent CSP for colorectal polyps ≤ 10 mm in size from March 2015 to September 2019, and cases of DB (DB group) were analyzed for the rate, antithrombotic drugs, polyp size, morphology, location, and risk factors. As a control, 269 non-bleeding cases (non-DB group) with 606 polyps who underwent CSP at the same 10 facilities in the 2-week study period were extracted.

RESULTS

We analyzed 26 DB cases with 28 lesions, and the total DB rate was 0.14% (26/18,007). The DB group had significantly higher rates of using antiplatelets (42.3% vs. 13.0%, p < 0.001) and anticoagulants (19.2% vs. 2.6%, p = 0.002), and significantly higher rates of polyp size ≥ 5 mm (67.9% vs. 45.2%, p = 0.015), rectal lesion (25.0% vs. 6.6%, p = 0.003), and polypoid lesion (89.3% vs. 55.3%, p < 0.001) than the non-DB group. A multivariate analysis (odds ratio; 95% confidence interval) for patient characteristics showed antiplatelet use (4.521; 1.817-11.249, p = 0.001) and anticoagulant use (7.866; 20.63-29.988, p = 0.003) as independent risk factors for DB. Polyp size ≥ 5 mm (3.251; 1.417-7.463, p = 0.005), rectal lesion (3.674; 1.426-9.465, p = 0.007), and polypoid lesion (7.087; 20.81-24.132, p = 0.002) were also risk factors for lesion characteristics.

CONCLUSIONS

The rate of DB was 0.14% and antithrombotic drug use, polyp size, location, and morphology were related to it.

Comparative evaluation of enema alone and in combination with oral polyethylene glycol for bowel preparation before transvaginal pelvic floor reconstruction in elderly patients: a retrospective cohort study

The aim of this retrospective study was to assess the value of using an enema alone for mechanical bowel preparation (MBP) before transvaginal pelvic floor reconstruction (TPFR) in patients ≥65 years old. In total, 190 patients were included [81 in the enema group vs. 109 in the enema + polyethylene glycol (PEG) group]. The levels of serum potassium (p = .004) and calcium (p = .005) were higher in the enema group after surgery. The decrease in serum calcium was more significant in the enema + PEG group (p = .027). More patients in the enema + PEG group developed hypokalaemia (p = .035) or hypocalcaemia (p = .008) after surgery. The incidence of thrombus and surgical site infection was similar and earlier bowel movement was evident in the enema group (p = .000). Overall, the enema group used more laxatives (p = .026). Using enema alone before TPFR reduces the incidence of electrolyte disturbances with no increase in surgical complications in elderly patients.IMPACT STATEMENTWhat is already known on this subject? TPFR is an effective treatment for pelvic organ prolapse (POP) in elderly women. Bowel preparation performed before gynecological surgery can reduce surgical site infection, but increase discomfort and electrolyte disturbance.What do the results of this study add? The levels of serum potassium and calcium were lower in the enema + PEG group than in the enema group after surgery and more patients developed hypokalaemia or hypocalcaemia in the enema + PEG group. The incidence of thrombus and surgical site infection was similar between the two groups. Bowel movement was earlier in the enema group.What are the implications of these findings for clinical practice and/or future research? Using enema alone before TPFR reduces the incidence of electrolyte disturbance and does not increase surgical complications. This conclusion needs to be confirmed by random controlled trial studies in the future.

The Efficacy of Tumor Characterization for Colorectal Lesions with Blue Light Imaging of a Compact Light-Emitting Diode Endoscopic System Compared to a Laser Endoscopic System: A Pilot Study

Background: A compact and cost-effective light source-processor combined 3-color light-emitting diode (LED) endoscopic system (ELUXEO-Lite: EP-6000, Fujifilm Co., Tokyo) with a magnified colonoscope (EC-6600ZP, Fujifilm Co.) has been released. Aims: In this study, we analyzed the efficacy of this system for colorectal tumor characterization with magnified blue light imaging (BLI-LED) and image's subjective and objective evaluations, compared to a magnified blue laser imaging (BLI-LASER) using a standard LASER endoscopic system. Methods: We retrospectively reviewed 37 lesions observed with both BLI-LED and BLI-LASER systems from 2019 using the Japanese narrow band imaging classification. Two representative magnified images, one BLI-LED and one BLI-LASER, of the same area of a lesion were evaluated for diagnostic accuracy and visualization quality by three experts and three non-experts. Their color difference values (CDVs) and brightness values (BVs) were also calculated as objective indicators. Results: Among 37 lesions, mean tumor size was 18.9 ± 13.1 mm, and 21 lesions were nonpolypoid. Histopathology revealed 14 sessile serrated lesions, 7 adenomas, 12 high-grade dysplasias and T1a cancers, and 4 T1b cancers. The diagnostic accuracy rates of BLI-LED/BLI-LASER of experts and non-experts were 90.1% and 87.4% (p = 0.52) and 89.2% and 89.2% (p = 0.99). The percentages of instances where BLI-LED images were better, the two imaging types were equivalent, or BLI-LASER images were better were 16%/83%/1% for experts and 19%/58%/23% for non-experts (p < 0.001). CDVs and BVs between BLI-LED and BLI-LASER were not significantly different (CDVs: p = 0.653, BVs: p = 0.518). Conclusions: BLI-LED using the compact system was noninferior to BLI-LASER for colorectal tumor characterization and image quality.

The usefulness of combining the pocket-creation method with a traction device using a scissor-type knife for colorectal endoscopic submucosal dissection

INTRODUCTION

Technical issues and long procedure time still remain a concern in colorectal endoscopic submucosal dissection (ESD). We examined the usefulness of combining the pocket-creation method (PCM) with a traction device (S-O clip; SO) using a scissor-type knife (Clutch Cutter 3.5 mm; CC) for decreasing ESD procedure time.

METHODS

We retrospectively analyzed 95 ESD cases of PCM + SO + CC managed from August 2017 to April 2020 and 103 cases of PCM + CC treated from July 2016 to July 2017. We compared these two groups through propensity score matching. The main outcome was the analysis of the ESD procedure times under various conditions in each group.

RESULTS

After matching, 52 cases in the PCM + SO + CC and PCM + CC groups were analyzed. The PCM + SO + CC group showed a significantly shorter ESD procedure time than the PCM + CC group (57.8 ± 31.4 vs. 81.7 ± 33.5 min, p < 0.01). Additionally, the ESD procedure time was significantly shorter in the PCM + SO + CC group than in the PCM + CC group: tumor size (tumor size < 40 mm: 45.6 ± 15.8 vs. 72.7 ± 22.9 min, p < 0.01; tumor size ≥ 40 mm: 83.1 ± 40.1 vs. 111.8 ± 45.3 min, p = 0.04), tumor location (right side: 64.7 ± 33.3 vs. 81.0 ± 29.7 min, p = 0.03; left side: 50.5 ± 28.0 vs. 82.3 ± 36.9 min, p < 0.01), tumor morphology (polypoid: 39.2 ± 18.6 vs. 74.7 ± 28.6 min, p < 0.01; nonpolypoid: 62.3 ± 32.3 vs. 84.5 ± 35.2 min, p < 0.01), endoscopist (expert: 67.3 ± 41.2 vs. 91.9 ± 40.2 min, p = 0.02; nonexpert: 50.4 ± 18.3 vs. 73.6 ± 24.9 min, p < 0.01), and fibrosis (severe fibrosis: 82.0 ± 20.5 vs. 99.8 ± 40.4 min, p = 0.169; non-severe fibrosis: 52.1 ± 23.8 vs. 75.6 ± 29.0 min, p < 0.01).

CONCLUSIONS

The combination of the PCM and SO using CC achieved a reduction in the colorectal ESD procedure time.

Novel frontiers of agents for bowel cleansing for colonoscopy

The incidence of colorectal cancer (CRC) is characterized by rapid declines in the wake of widespread screening. Colonoscopy is the gold standard for CRC screening, but its accuracy is related to high quality of bowel preparation (BP). In this review, we aimed to summarized the current strategy to increase bowel cleansing before colonoscopy. Newly bowel cleansing agents were developed with the same efficacy of previous agent but requiring less amount of liquid to improve patients’ acceptability. The role of the diet before colonoscopy was also changed, as well the contribution of educational intervention and the use of adjunctive drugs to improve patients’ tolerance and/or quality of BP. The review also described BP in special situations, as lower gastrointestinal bleeding, elderly people, patients with chronic kidney disease, patients with inflammatory bowel disease, patients with congestive heart failure, inpatient, patient with previous bowel resection, pregnant/lactating patients. The review underlined the quality of BP should be described using a validate scale in colonoscopy report and it explored the available scales. Finally, the review explored the possible contribution of bowel cleansing in post-colonoscopy syndrome that can be related by a transient alteration of gut microbiota. Moreover, the study underlined several points needed to further investigations.

Effects of the combined use of a scissor-type knife and traction clip on endoscopic submucosal dissection of colorectal tumors: a propensity score-matched analysis

Background and study aims  This study evaluated the technical aspects of colorectal endoscopic submucosal dissection (ESD) with the Clutch Cutter (CC) (Fujifilm Co., Tokyo, Japan), a scissor-type knife, and the S-O clip (SO) as a traction clip, and compared the safety and efficacy to ESD using a needle-type knife. Patients and methods  This was a single-center retrospective study. In Study 1, we evaluated 125 ESD patients: 60 using the SO and CC (SO group) and 65 using the CC (CC group). In Study 2, we evaluated 185 ESD patients: the CC group (N = 65) and 120 using the Flush knife BT-S (Flush group) (Fujifilm Co., Tokyo, Japan). In both studies, the clinicopathological features and therapeutic outcomes were compared using a propensity score-matched analysis. Results  In 36 pairs of matched patients in Study 1, the rates of en bloc resection, R0 resection, perforation, and postoperative bleeding (POB) were 97.2 %, 88.9 %, 2.8 %, and 0 %, respectively, for the SO group and 100 %, 91.7 %, 0 %, and 0 % for the CC group (not significant). The mean procedure time for the SO group among less-experienced endoscopists was significantly shorter than in the CC group (42 vs. 65 minutes, P  = 0.036). In 49 pairs of matched patients in Study 2, the rates of en bloc resection, R0 resection, perforation, and POB were 100 %, 95.8 %, 0 %, and 0 %, respectively, for the CC group and 98.0 %, 95.8 %, 0 %, and 2.0 % for the Flush group (not significant). The mean procedure time in the CC group among less-experienced endoscopists was significantly shorter than in the Flush group (52 vs. 67 minutes, P  = 0.038). Conclusions  CC and the combined use of CC and SO reduced colorectal ESD procedure time among less-experienced endoscopists.

Safety and efficacy of sodium picosulfate, magnesium oxide, and citric acid bowel preparation in patients with baseline renal impairment or diabetes: subanalysis of a randomized, controlled trial

BACKGROUND

Selecting a bowel preparation for patients with renal impairment or diabetes requires special consideration. We aimed to describe the effect of baseline renal impairment or diabetes on the safety, efficacy, and tolerability of low-volume sodium picosulfate, magnesium oxide, and citric acid (SPMC) ready-to-drink oral solution bowel preparation.

METHODS

A post hoc secondary analysis was performed from a randomized, assessor-blinded study of SPMC oral solution bowel preparation in participants with mild or moderate baseline renal impairment or diabetes. Primary efficacy endpoint ('responders') was the proportion of participants with 'excellent' or 'good' ratings on a modified Aronchick Scale (AS). Secondary efficacy outcomes were the quality of ascending colon cleansing from the Boston Bowel Preparation Scale (BBPS), and selected results from the Mayo Clinic Bowel Prep Tolerability Questionnaire. Safety assessments included adverse events (AEs), adenoma detection, and laboratory evaluations.

RESULTS

Similar overall colon cleansing was demonstrated in the subgroups, with >85% of participants in any subgroup rated as responders by the AS, and >92% of participant responders by the BBPS. Most participants reported a tolerable bowel preparation, regardless of baseline renal impairment or diabetes history. Safety of SPMC oral solution was similar between all subgroups and the overall cohort. For the mild renal impairment, moderate renal impairment, and diabetes subgroups, respectively, commonly reported, drug-related AEs were nausea (2.6%, 5.3%, 1.4%) and headache (2.2%, 2.6%, 4.3%).

CONCLUSIONS

Ready-to-drink SPMC oral solution demonstrated efficacious colon cleansing in patients with baseline mild/moderate renal impairment or diabetes, with a tolerable bowel preparation reported by most.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov identifier: NCT03017235.

Safety of Polyethylene Glycol Solution plus Ascorbic Acid for Bowel Preparation for Colonoscopy in Patients with Chronic Kidney Disease

INTRODUCTION

Polyethylene glycol-electrolyte lavage solution plus ascorbic acid (PEG-ELS-Asc) has been recommended for colonoscopy, but little is known about the safety of PEG-ELS-Asc in patients with chronic kidney disease (CKD). The aim of this study was to determine its safety and efficacy in CKD patients.

METHODS

Blood and urine samples prospectively collected before and after same-day bowel preparation for colonoscopy with the conventional volume of PEG-ELS-Asc, vital signs before and after colonoscopy, and adverse events within 30 days postcolonoscopy were analyzed in consenting patients with CKD. The cleansing level was evaluated with the Boston bowel preparation score (BBPS) from colonoscopic findings.

RESULTS

Of 57 patients enrolled, 1 was excluded for refusal. Serum bicarbonate significantly dropped, and blood hemoglobin, serum total protein, albumin, aspartate aminotransferase, alanine aminotransferase, lactate dehydrogenase, total bilirubin, and uric acid significantly rose after bowel preparation, although these changes were not clinically important. Only in nondialysis patients did the platelet count and potassium significantly rise, although these changes were not clinically important either. Renal function, such as the urea, creatinine, and estimated glomerular filtration rate, was not significantly altered. An adequate bowel cleansing score, BBPS ≥ 6, was achieved in 94% of patients. The blood pressure and heart rate were not significantly different between before and after colonoscopy in either nondialysis (n = 32) or dialysis (n = 19) patients. There were no adverse events associated with bowel preparation and colonoscopy within 30 days postcolonoscopy.

CONCLUSIONS

The conventional volume of same-day bowel preparation with PEG-ELS-Asc may be safe and effective in CKD patients.

Cold snare polypectomy for large sessile serrated lesions is safe but follow-up is needed: a single-centre retrospective study

Background and Aim

Cold snare polypectomy (CSP) is growing in popularity due to its safety and convenience. Its indication is benign tumours such as adenoma and sessile serrated lesions (SSLs) <10 mm in size. CSP for SSLs ≥10 mm in size has not been well examined. In this study, we aimed the feasibility of this treatment regarding therapeutic results and local recurrence.

Methods

This was a single‐centre retrospective cohort study. We reviewed SSLs with or without dysplasia of 10–20 mm that were resected by CSP from 2014 to 2020. All tumours were diagnosed endoscopically as SSLs without dysplasia before CSP with the help of magnifying narrow band imaging or blue laser imaging. We analysed the lesion characteristics, en bloc resection, histopathological diagnosis, adverse events and local recurrence. We analysed risk factors for recurrence, comparing recurrent lesions to non‐recurrent lesions. We also compared risk factors for lesions 10–14 mm in size to those for lesions 15–20 mm in size.

Results

We analysed 160 lesions in 100 patients (M_age ± SD = 67.7 ± 10.1 years). The polyp size (M ± SD) was 11.8 ± 2.8 mm, and the en bloc resection rate was 60.0% (96 cases). The rates of massive perioperative haemorrhage, postoperative haemorrhage and perforation were 1.3%, 0% and 0%, respectively. Regarding histopathological diagnosis, two (1.2%) cases showed SSLs with high‐grade dysplasia. The recurrence rate in 101 lesions with a median follow‐up period of 18 months (interquartile range 12–24 months) was 5.0%. There were no significant risk factors such as tumour size, location, morphology and so on in terms of recurrence. All recurrent cases could be resected by repeat CSP. The recurrence rates of lesions 10–14 mm in size and 15–20 mm in size were 4.7% and 6.3%, respectively (p = 0.713).

Conclusion

CSP of SSLs ≥10 mm in size according to magnifying endoscopic diagnosis was safe and promising, but the rate of recurrence was slightly high, meaning that close follow‐up is required.

The Efficacy of Short-Duration Polyethylene Glycol plus Electrolytes for Improving Bowel Preparation of Colonoscopy in Patients with Chronic Constipation

Materials and Methods

This multicenter retrospective study was conducted from September 2019 to September 2020 at 5 related institutions among patients ≥ 20 years old diagnosed with chronic constipation whose previous colonoscopic BP had had a fair or poor Aronchick score. Two or four sachets of PEG+E (13.7 or 27.4 g/day) were prescribed for 1 week before colonoscopy. We analyzed the rate of improvement in BP, effect-related factors, spontaneous bowel movements (SBMs), stool consistency, improvement of constipation symptoms, and adverse events.

Results

We evaluated 106 cases (56 males) with an average age of 69.5 ± 9.4 years old (≤74 years old: 68 cases, ≥75 years old: 38 cases). The improvement rate of BP was 72.6%, and the insertion time and pain score also improved. A performance status of 1 or 2 was associated with poor BP. SBMs (times/week) increased from 4.0 ± 1.9 to 6.1 ± 2.6 (p < 0.001). The overall improvement rates of SBMs, stool consistency, symptoms of constipation, and rate of adverse events were 58.5%, 90.6%, 59.4%, and 6.6%, respectively, showing no significant differences with regard to age or gender.

Conclusions

Short-duration PEG+E was effective for improving poor BP and chronic constipation.

The efficacy and safety of colonoscopy in nonagenarians: A multicenter study

INTRODUCTION

The number of colonoscopy (CS) for the elderly is increasing. There are only a few reports focusing on CS among the very elderly aged ≥ 90-y. We aimed to analyze the efficacy of CS and of colorectal cancer (CRC) for patients aged ≥ 90-y.

METHODS

We retrospectively analyzed consecutive patients aged ≥ 90-y receiving CS at eight institutions from October 2016 to September 2017. Bowel preparation, complications, and endoscopic diagnosis were analyzed. The non-elderly group aged between 50-y and 64-y and elderly group aged between 65-y and 79-y were compared to very-elderly group aged ≥ 90-y. Through propensity score matching of sex and CS indications (symptomatic or asymptomatic), the number of CRC and the treatment in each group were analyzed.

RESULTS

We analyzed 125 patients receiving 154 colonoscopies (0.9%) in the very-elderly group from among 16,968 cases. Among 92 cases who received bowel-cleansing solution, good preparations were achieved in 94.5%. The rate of CS-related complications was 1.3% (2/154). The rate of CRC in the very-elderly group was 27.2% (34/125), higher than the non-elderly group (7.2%, 9/125, p < 0.01) and elderly group (8.8%, 11/125, p < 0.01). Therapeutic interventions for CRC in the very-elderly group were performed in 73.5% (24/34) patients. The mean survival of 12 patients with CRC resection was 788 days.

CONCLUSIONS

CS could be performed safely for the very elderly aged ≥ 90-y with careful considerations. CRC was confirmed to be more frequent in this group with over 70% of patients receiving appropriate therapeutic intervention.

Comparison Between Linked Color Imaging and Blue Laser Imaging for Improving the Visibility of Flat Colorectal Polyps: A Multicenter Pilot Study

INTRODUCTION

Linked color imaging (LCI) and blue laser imaging-bright (BLI-b) improve the visibility of gastrointestinal lesions. In this multicenter study, we compared the effects of LCI and BLI-b on the visibility of flat polyps with visibility scores and color difference (CD) values, including fast-withdrawal and large-monitor observation.

METHODS

We recorded 120 videos of 40 consecutive flat polyps (2-20 mm), adenoma, and sessile serrated adenoma and polyp (SSA/P), using white light imaging (WLI), BLI-b, and LCI from July 2017 to December 2017. All videos were evaluated by eight endoscopists according to a published polyp visibility score of 4 (excellent) to 1 (poor). Additionally, 1.5 ×faster and 1.7 ×sized videos were evaluated. Moreover, we calculated the CD values for each polyp in three modes.

RESULTS

The mean LCI scores (3.1 ± 0.9) were significantly higher than the WLI scores (2.5 ± 1.0, p < 0.001) but not significantly higher than the BLI-b scores (3.0 ± 1.0). The scores of faster videos on LCI (3.0 ± 1.1) were significantly higher than WLI (2.0 ± 1.0, p < 0.001) and BLI-b (2.8 ± 1.1, p = 0.03). The scores of larger-sized videos on LCI were not significantly higher than those of WLI or BLI-b. The CD value of LCI (18.0 ± 7.7) was higher than that of WLI (11.7 ± 7.0, p < 0.001), but was not significantly higher than that of BLI-b (16.6 ± 9.6). The CD value of LCI was significantly higher than that of BLI-b for adenoma, but the CD value of BLI-b was significantly higher than that of LCI for SSA/P.

CONCLUSIONS

The superiority of LCI to BLI-b was proven for the visibility of adenoma and fast observation.

The efficacy of tumor characterization and tumor detectability of linked color imaging and blue laser imaging with an LED endoscope compared to a LASER endoscope

OBJECTIVES

An endoscope with a light-emitting diode (LED) light source which has a 2-mm close-distance observation function without magnification, has been marketed, enabling linked color imaging (LCI) and blue laser imaging (BLI) for tumor detection and characterization. We analyzed the efficacy of a LED endoscope compared to a LASER endoscope.

METHODS

We retrospectively reviewed 272 lesions observed using the LED endoscopic system (Fujifilm Co., Tokyo, Japan) from May 2018 to September 2019. The Japanese NBI Classification was used for tumor characterization. We analyzed the diagnostic accuracy and confidence level. Sixty-one lesions observed with both the LED and magnified LASER endoscopes were also analyzed to compare the diagnostic accuracy. Regarding the tumor detectability, we calculated color difference values (CDVs) and brightness values (BVs) of white-light imaging, BLI, and LCI modes between the two endoscopes for each tumor.

RESULTS

The mean polyp size was 9.2 ± 11.3 mm. Histology showed 71 sessile serrated lesions, 193 adenoma and high-grade dysplasias, and 8 T1 cancers. The diagnostic accuracy of tumors ≥ 10 and < 10 mm was 72.0% and 92.9% (p < 0.001), respectively and the high confidence rate was 93.8%. The diagnostic accuracy of LED (77.0%) was a little higher than that of LASER without magnification (65.6%, p = 0.16) but was not inferior to that of LASER with magnification (82.0%, p = 0.50). The respective CDVs of LED and LASER endoscopes were 20.6 ± 11.2 and 21.6 ± 11.2 for LCI (p = 0.30), and the respective BVs were 210.0 ± 24.2 and 175.9 ± 21.1 (p < 0.001).

CONCLUSIONS

A LED endoscope with close-distance observation improved tumor detection and characterization due to high brightness.

A Randomized, Endoscopist-Blinded, Prospective Trial to Compare the Efficacy and Patient Tolerability between Bowel Preparation Protocols Using Sodium Picosulfate Magnesium Citrate and Polyethylene-Glycol (1 L and 2 L) for Colonoscopy

Patient compliance during bowel preparation is important for successful colonoscopy. Bowel preparation with polyethylene glycol (PEG), the most commonly used solution for cleansing, involves the unpleasant ingestion of a large amount of liquid. Sodium picosulfate magnesium citrate (SP-MC) solution is an alternative option with better palatability than PEG. Therefore, in this study, we compared the efficacy and patient tolerability among the following three bowel preparation protocols: 2 L PEG-ascorbic acid (ASc), 1 L PEG-ASc plus bisacodyl, and SP-MC 340 mL plus bisacodyl. We conducted a randomized prospective endoscopist-blinded study between August 2018 and January 2019. A total of 311 patients were randomly classified into three groups according to the above-described bowel preparation protocols. To evaluate the efficacy of bowel cleansing, we used the Boston Bowel Preparation Scale. The degree of symptoms and the patients' satisfaction with each bowel preparation method were investigated using a questionnaire completed before sedation for colonoscopy. The baseline characteristics were similar among the three groups. There was no significant difference in the bowel preparation quality among the three groups. However, the incidence of symptoms, such as abdominal fullness and pain, was significantly lower (P = 0.006 and 0.027, respectively) while the patients' satisfaction rate was significantly higher (P = 0.012) in the SP-MC plus bisacodyl group than in the two PEG groups. In this study, the efficacy of the SP-MC plus bisacodyl solution was similar to that of the PEG solutions. However, patient tolerability and satisfaction were better in the SP-MC plus bisacodyl group than in the other groups. In conclusion, the use of SP-MC plus bisacodyl bowel preparation solution might be a better method for providing good intestinal cleansing and improving patient compliance.

Multicenter Study of the Hemorrhage Risk after Endoscopic Mucosal Resection Associated with Direct Oral Anticoagulants

Backgrounds and Aims

Recently, direct oral anticoagulants (DOACs) have become widely used for preventing thromboembolism. However, postoperative hemorrhage (POH) is a major complication associated with endoscopic mucosal resection (EMR) for colorectal lesions. In this multicenter study, we analyzed the incidence of POH after EMR associated with DOACs and explored the associated risk factors.

Materials and Methods

This study was a multicenter retrospective cohort study conducted at 8 Japanese institutions. A total of 2062 cases that underwent EMR for colorectal lesions at these 8 institutions from October 2016 to September 2017 were analyzed. The cases were divided into 4 groups: the DOAC group (63 cases), warfarin group (34 cases), antiplatelet group (185 cases), and no antithrombotics group (1780 cases). In all lesions of the DOAC and warfarin groups, endoscopic clipping was performed after EMR. The rate of POH in the DOAC group, patients' clinical characteristics, the risk factors of POH, and the rate of thromboembolism due to stopping DOACs were compared with other groups.

Results

The rates of POH were 7.9%^∗ (5/63), 2.9% (1/34), 3.2% (6/185), and 0.6%^∗∗ (11/1780) in the DOAC, warfarin, antiplatelet, and no antithrombotics groups, respectively (^∗ vs. ^∗∗, p < 0.001). Regarding risk factors, the tumor size with POH (mm) was significantly bigger than that without POH (16.2 ± 8.3 vs. 7.2 ± 4.9, p < 0.001). There were no significant differences in the rates of POH based on the type of DOAC. In addition, no thromboembolisms occurred due to stopping of DOAC treatment.

Conclusions

Patients receiving DOACs had significantly higher rates of POH after EMR than those without antithrombotics.

An Additional 30-s Observation of the Right-Sided Colon with Narrow Band Imaging Decreases Missed Polyps: A Pilot Study

INTRODUCTION

Previous narrow-band imaging (NBI) was dark and reported not to be useful for polyp detection. In this study, we analyzed the efficacy of an additional 30-s observation of the right-sided colon with the recent bright high-resolution NBI.

METHODS

We enrolled patients undergoing colonoscopy from February 2015 to May 2017 in two institutions. All procedures were performed with the latest system (EVIS LUCERA ELITE, Olympus). The cecum and ascending colon were first observed with white light imaging (WLI) in both the NBI and WLI group. Then, the colonoscope was re-inserted, and the cecum and ascending colon were observed for an additional 30 s. In this second observation, NBI was performed for the first 130 patients in the NBI group and WLI for the next 130 in the WLI group. The number of adenoma and sessile serrated polyps (ASPs) in the second observation were examined in both groups. According to our initial pilot study, the sample size was estimated at 126.

RESULTS

In the first observation, the number of ASPs was 72 in the NBI group and 72 in the WLI group (p = 1.0). In the second observation, the number of ASPs was 23 in the NBI group and 10 in the WLI group (p = 0.02). The polyp and adenoma detection rates in the second observation were 16.2% and 12.3% in the NBI group and 7.7% (p = 0.03) and 6.2% (p = 0.09) in the WLI group.

CONCLUSIONS

The additional 30-s observation with recent NBI decreased missed polyps in the right-sided colon.

Acute Myocardial Infarction Following Administration of Polyethylene Glycol Electrolyte Solution with Ascorbic Acid (MoviPrep®) at Home: A Case Report

A male individual aged 82 years with hypertension who had a smoking history, but no history of cardiovascular events, developed acute myocardial infarction immediately after he took oral polyethylene glycol electrolyte solution with ascorbic acid as a pretreatment for a colonoscopy to examine anemia. He took polyethylene glycol electrolyte solution with ascorbic acid at twice (2 L/h) the rate recommended in the package insert and by the physician. The patient showed impaired consciousness 2 h after taking polyethylene glycol electrolyte solution with ascorbic acid and his family called the emergency medical service. Upon arrival of the emergency medical service, his systolic blood pressure was 60 mmHg and heart rate was 50 bpm. Systolic blood pressure and impaired consciousness were slightly improved, but compensatory shock remained, at arrival at the emergency outpatient service at our hospital. No dyspnea or rash was apparent. The patient had no subjective chest pain; however, ST-segment elevation was detected in the electrocardiogram at II, III, aVF, V3R, and V4R. He was diagnosed with ST-segment elevation myocardial infarction and underwent a coronary catheter intervention for total occlusion of the right coronary artery. His shock state was abolished by this intervention. The patient was pretreated with polyethylene glycol electrolyte solution with ascorbic acid under close watch in the coronary care unit 4 days later, with no relapse of symptoms. Advanced cancer was found in the ileocecum by colonoscopy; consequently, the patient underwent a colectomy and was discharged from our hospital and transferred to another hospital for rehabilitation on hospital day 74. A Naranjo assessment score of 4 was obtained, indicating a possible relationship of acute myocardial infarction with misuse of the suspect drug, polyethylene glycol electrolyte solution with ascorbic acid.

The efficacy of the pocket-creation method for cases with severe fibrosis in colorectal endoscopic submucosal dissection

BACKGROUND AND STUDY AIMS

 Severe fibrosis poses a challenge in colorectal endoscopic submucosal dissection (ESD). Recently, the pocket-creation method (PCM) has been developed for overcoming various difficulties of ESD. A specific tapered hood is used for adequate traction in the PCM, and endoscopic operability becomes stable in the pocket. In this study, we investigated the efficacy of the PCM in ESD for cases with severe fibrosis.

PATIENTS AND METHODS

We retrospectively reviewed 1000 consecutive colorectal ESD cases (April 2006 to January 2017). Since 2016, the PCM was performed in 58 cases. The indications for ESD included (1) tumors ≥ 20 mm in size diagnosed as intramucosal cancer or high-grade dysplasia and part of T1a cancer using magnifying endoscopic examinations and (2) tumors that appeared impossible to resect with endoscopic mucosal resection because of suspected fibrosis. We identified 120 cases with severe fibrosis and compared them to cases without severe fibrosis. Additionally, the 120 severe fibrosis cases were divided into the PCM and non-PCM groups. En bloc resection, procedure time, discontinuation, and complications were analyzed between these 2 groups.

RESULTS

 Among all 1000 ESDs, severe fibrosis and discontinuation rates were 12.0 % (120 cases) and 1.8 % (18 cases), respectively. Regarding the comparison between cases with severe fibrosis and with no severe fibrosis, there were significant differences about en bloc resection rate (78.3 % vs. 95.7 %, P  < 0.001), discontinuance rate (12.5 % vs. 0.3 %, P  < 0.001), and perforation rate (8.3 % vs. 2.6 %, P  = 0.001). Among the 120 cases with severe fibrosis, 21 and 99 cases were in the PCM and non-PCM groups, respectively. The PCM group had a higher en bloc resection rate (95.2 vs. 74.7, P  =  0.03), a shorter mean procedure time (min) (79.6 ± 26.5 vs. 118.8 ± 71.0, P  = 0.001), and no cases of discontinuation. An analysis of the interobserver agreement for the diagnosis of severe fibrosis among the 3 endoscopists showed kappa values of > 0.6.

CONCLUSIONS

 In cases with severe fibrosis, the PCM with ESD improved en bloc resection rates and shortened the procedure time compared to the conventional non-PCM method. Additionally, the PCM reduced the discontinuation rate.

Additional Thirty Seconds Observation with Linked Color Imaging Improves Detection of Missed Polyps in the Right-Sided Colon

Background and Aims

Missed polyps are a pitfall of colonoscopy. In this study, we analyzed the efficacy of an additional 30 seconds observation using linked color imaging (LCI) for detecting adenoma and sessile serrated adenoma/polyp (SSA/P).

Materials and Methods

We enrolled patients undergoing colonoscopy from February to October 2017 in two institutions. In all patients, the cecum and ascending colon were observed with white light imaging (WLI) first. The colonoscope was inserted again, and the cecum and ascending colon were observed for an additional 30 seconds using either LCI or WLI. The method for the 30 sec observation was to insufflate the cecum and ascending colon sufficiently and observe them in a distant view, because the length of the second observation was determined to be precisely 30 sec. For the second observation, LCI was performed for the first 65 patients and WLI for the next 65. Adenoma and SSA/P detection rate (ASDR) in the second observation were examined in both groups. According to a pilot study, the sample size was estimated 65.

Results

In the first observation, ASDR were 30.7% in the LCI group and 32.2% in the WLI group (p = 0.85). For the second observation, 13 polyps were detected in the LCI group and 5 polyps in the WLI group (p = 0.04). Additionally, ASDR for the second observation were 18.5% and 6.1%, respectively (p = 0.03). There were no significant differences between the LCI and WLI groups with respect to morphology (ratio of polypoid) (38.5% versus 60.0%, p = 0.52) and histology (ratio of adenoma) (92.3% versus 100.0%, p = 0.91). Total adenoma and SSA/P number were 48 in the LCI group and 36 in the WLI group (p = 0.02).

Conclusion

The 30 seconds additional observation with LCI improved the detection of adenoma and SSA/P in the right-sided colon.

A circumferential rectal superficial neoplasm resected with endoscopic submucosal dissection using the pocket-creation method

Endoscopic submucosal dissection (ESD) is recognized as an important technique in the nonsurgical management of early gastrointestinal carcinoma and it is continuously undergoing evolution in terms of technique and equipment. The pocket-creation method was recently developed for overcoming various difficulties such as large tumor size and severe fibrosis in ESD. Circumferential ESDs are rare and pose technical difficulties. We present a case of a circumferential rectal ESD using a pocket-creation method with two pockets. The associated planning, strategies, and outcome of the procedure are discussed.

Polyethylene glycol-based bowel preparation before colonoscopy for selected inpatients: A pilot study

OBJECTIVE

To evaluate the impact of a new same-day, low-dose 1-L polyethylene glycol-based (1-L PEG) bowel preparation on the diagnostic rating of selected hospitalized patients and its tolerability, with risk factors for inadequate bowel preparation.

METHODS

A single-center prospective pilot study was conducted with hospitalized patients scheduled for colonoscopy, presenting risk factors for poor bowel preparation, such as bleeding or subocclusive symptoms. The included patients were randomly divided in two groups, which received either a same-day 1-L PEG (group A) or a split-dose 4-L PEG (group B), and performed a colonoscopy within 4 h of the last dose.

RESULTS

In all, 44 inpatients [27 males; mean age 63.5 years (range 20-94 years)] were enrolled. Optimal bowel cleansing was reached in 64% and 55% (P = 0.64) of patients in groups A and B, respectively. The adenoma detection rate was 14% (group A) and 18% (group B) (P = 0.34). A valid diagnosis was reached in 38 (86%) of 44 patients (21 in group A and 17 in group B) after a mean hospitalization of 3 days for group A and 6 days for group B (P = 0.04).

CONCLUSIONS

Our data support the conclusion that the schedule protocol proposed in this study enables a clear diagnosis in most of the inpatients at high risk of poor bowel preparation and no statistical differences were found between the two groups in terms of successful bowel cleansing achieved. Therefore, the same-day, low-dose 1-L PEG bowel preparation could be introduced for selected inpatients.

Linked color imaging improves the visibility of various featured colorectal polyps in an endoscopist's visibility and color difference value

PURPOSE

Linked color imaging (LCI) by laser endoscopy is a novel narrow band light observation. In this study, we analyzed the efficacy of LCI for improving the various featured colorectal polyp's visibility utilizing a subjective endoscopist's visibility scoring and objective color difference (CD) value.

METHODS

We retrospectively reviewed two pictures both with white light (WL) and LCI for 54 consecutive neoplastic polyps 2-20 mm in size. All pictures were evaluated by four endoscopists according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, we calculated CD value between each polyp and surrounding mucosa in LCI and WL using an original software.

RESULTS

The mean polyp visibility scores of LCI (3.11 ± 1.05) were significantly higher than those of WL (2.50 ± 1.09, P < 0.001). The ratio of an endoscopist's poor visibility (polyp visibility scores 1 and 2) was significantly lower in LCI (27.9%) than WL (55.6%, P < 0.001). With respect to the CD analysis, the CD value of LCI was significantly higher than that of WL (33.3 ± 13.9 vs. 20.7 ± 13.6, P < 0.001). In a subgroup analysis, the polyp visibility scores and CD values of LCI about 24 diminutive polyps (≤5 mm) were higher than those of WL (3.29 ± 0.99 vs. 2.12 ± 0.99, P < 0.001; 31.6 ± 12.8 vs. 14.7 ± 7.6, P < 0.001). Additionally, the polyp visibility scores and CD values of LCI for polyps with any location, size, histology, and morphology were significantly higher than those of WL.

CONCLUSIONS

LCI improved the various featured polyp's visibility compared to WL in both polyp visibility scores and CD value.

The management of 'hard-to-prepare' colonoscopy patients

Effective bowel cleansing is crucial for high quality colonoscopy. A notable portion of patients still present with low quality bowel preparation prior to their colonoscopy, compromising the overall quality of their colonoscopy. Areas covered: This review focuses on the main strategies that can improve the cleansing quality with a special interest on those clinical conditions that have been associated with a poor bowel preparation quality, such as patients with chronic constipation, history of bowel resection, liver cirrhosis, diabetes mellitus and chronic kidney disease. The review provides a practical and evidence-based approach to help clinicians in the management of 'hard-to-prepare' patients. Expert commentary: In the past few years, the quality of colonoscopy has become a hot topic and bowel cleansing is a crucial part of it; however, the approach to patients with an increased risk of poor bowel preparation quality is still not always supported by high-quality evidence, since most of these patients are routinely excluded from the clinical studies. Trials focused on this subgroup of patients are recommended to provide tailored bowel preparation regimens and guarantee high-quality procedures.

Histopathological analysis of cold snare polypectomy and its indication for colorectal polyps 10-14 mm in diameter

BACKGROUND AND AIM

Cold snare polypectomy (CSP) is commonly used for treating colorectal polyps <10 mm in diameter. We evaluated the analysis and safety of CSP for larger polyps.

METHODS

We retrospectively analyzed 1006 colorectal polyps resected with CSP. Indication for CSP was polyps 2-14 mm that were diagnosed as benign neoplastic polyp by magnifying endoscopy. Various clinicopathological characteristics were analyzed. Multivariate analyses were used to determine the independent risk factors for failure of complete CSP resection. With respect to polyp size, we compared the therapeutic outcomes between polyps <10 mm and ≥10 mm. Additionally, the presence of muscularis mucosa in resected specimens was analyzed.

RESULTS

Rates of en bloc resection and postoperative hemorrhage were 98.8% and 0.1%, respectively. Seven hundred and ninety-one neoplastic lesions were analyzed and negative margins were found in 70.5% of the lesions, Multivariate analysis showed that non-polypoid morphology, histology of intramucosal cancer + high-grade adenoma and sessile serrated adenoma and polyp were significant factors for incomplete resection. With respect to the difference between lesions ≥10 mm than in those <10 mm, rates of cancer and positive/unclear margins were significantly higher (5.0% vs 0.9%, P < 0.001; 40.6% vs 27.7%, P = 0.007) in the ≥10 mm with rates of postoperative hemorrhage not significantly different (0.8% vs 0.0%). Additionally, the loss of muscularis mucosa was found in 27.8% of all lesions.

CONCLUSION

CSP is a safe procedure for polyps 2-14 mm. However, CSP has limitations in terms of the histopathological margin and loss of muscularis mucosa in specimens.

Linked color imaging improves the visibility of colorectal polyps: a video study

BACKGROUND/STUDY AIM

 Linked color imaging (LCI) by a laser endoscope (Fujifilm Co, Tokyo, Japan) is a novel narrow band light observation. In this study, we aimed to investigate whether LCI could improve the visibility of colorectal polyps using endoscopic videos.

PATIENTS AND METHODS

 We prospectively recorded videos of consecutive polyps 2 - 20 mm in size diagnosed as neoplastic polyps. Three videos, white light (WL), blue laser imaging (BLI)-bright, and LCI, were recorded for each polyp by one expert. After excluding inappropriate videos, all videos were evaluated in random order by two experts and two non-experts according to a published polyp visibility score from four (excellent visibility) to one (poor visibility). Additionally, the relationship between polyp visibility scores in LCI and various clinical characteristics including location, size, histology, morphology, and preparation were analyzed compared to WL and BLI-bright.

RESULTS

 We analyzed 101 colorectal polyps (94 neoplastic) in 66 patients (303 videos). The mean polyp size was 9.0 ± 8.1 mm and 54 polyps were non-polypoid. The mean polyp visibility scores for LCI (2.86 ± 1.08) were significantly higher than for WL and BLI-bright (2.53 ± 1.15, P  < 0.001; 2.73 ± 1.47, P  < 0.041). The ratio of poor visibility (score 1 and 2) was significantly lower in LCI for experts and non-experts (35.6 %, 33.6 %) compared with WL (49.6 %, P  = 0.015, 50.5 %, P  = 0.046). The polyp visibility scores for LCI were significantly higher than those for WL for all of the factors. With respect to the comparison between BLI-bright and WL, the polyp visibility scores for BLI-bright were not higher than WL for right-sided location, < 10 mm size, sessile serrated adenoma and polyp histology, and poor preparation. For those characteristics, LCI improved the lesions with right-sided location, SSA/P histology, and poor preparation significantly better than BLI.

CONCLUSIONS

 LCI improved polyp visibility compared to WL for both expert and non-expert endoscopists. It is useful for improving polyp visibility in any location, any size, any morphology, any histology, and any preparation level.