History and Development of Accessories for Endoscopic Submucosal Dissection

Settings of a novel electrosurgical generator to enable efficient and safe submucosal endoscopic procedures

Background and study aims A novel electrosurgical generator unit (ESU), ConMed Beamer, was recently introduced to facilitate endoscopic submucosal dissection (ESD) by employing Automatic Cutting Effect (ACE) technology. Its use in submucosal endoscopy has yet to be investigated. The aim of this study was to evaluate the feasibility and safety of performing ESD and peroral endoscopic myotomy (POEM) using novel settings generated with ConMed Beamer ESU. Patients and methods This was a single-center prospective study of 59 consecutive patients undergoing ESD/POEM at a tertiary referral center. ESU settings were initially generated by testing in live animal models prior to first in-human study. The primary outcome was technical success. Secondary outcomes were procedure times, rate of en bloc/R0 resection, and rate of adverse events (AEs). Results A total of 44 patients (50 polyps) and 15 patients underwent ESD and POEM, respectively. En bloc resection, R0 resection, and curative resection rates were 90%, 77.1%, and 70.8%, respectively. Mean maximal length of the lesion was 3.07 cm ± 1.43 with an average dissection speed of 14.2 cm 2 /hr ± 11.1. Technical success was achieved in 100% of POEM patients. Mean time (minutes) to complete the POEM procedure was 50.1 min ± 12.4. Two major AEs occurred among all patients (3.4%). All intraprocedural bleeding events were controlled using the ConMed Beamer ESU. Conclusions ConMed Beamer ESU settings generated from this study were proven safe and effective in a prospective cohort of patients who underwent submucosal endoscopic procedures. This novel ESU can be added to the armamentarium of ESD capable generators.

Efficacy and Safety of ClearCut™ Knife H-type in Endoscopic Submucosal Dissection for Gastric Neoplasms: A Multicenter, Randomized Trial

PURPOSE

Endoscopic submucosal dissection (ESD) is an effective treatment for early gastrointestinal neoplasms. However, this is a time-consuming procedure requiring various devices. This study aimed to evaluate the efficacy and safety of the ClearCut™ Knife H-type, which is an integrated needle-tipped and insulated-tipped (IT) knife.

MATERIALS AND METHODS

Between July 2020 and September 2021, 99 patients with gastric epithelial neoplasms scheduled for ESD at three tertiary care hospitals were randomly assigned to H-knife (ClearCut™ Knife H-type) or IT-knife (conventional IT knife) groups. Procedure times, therapeutic outcomes, and adverse events were analyzed.

RESULTS

A total of 98 patients (50 in the H-knife group and 48 in the IT-knife group) were analyzed. The median total procedure time was 11.9 minutes (range, 4.4-47.2 minutes) in the H-knife group and 12.7 minutes (range, 5.2-137.7 minutes) in the IT-knife group (P=0.209). Unlike the IT-knife group, which required additional devices in all cases, no additional devices were used in the H-knife group (P<0.001). En-bloc resection was performed for all lesions in both groups. The incidence of adverse events was not significantly different between groups (4.0% in the H-knife group vs. 8.3% in the IT-knife group; P=0.431).

CONCLUSIONS

The newly developed hybrid device, the ClearCut™ Knife H-type, had comparable efficacy to the conventional IT knife for gastric ESD.

TRIAL REGISTRATION

Clinical Research Information Service Identifier: KCT0005164.

Design and validation of performance-oriented injectable chitosan thermosensitive hydrogels for endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a challenging procedure. The use of biomaterials to improve the operator's convenience (operating affinity) has received little attention. We prepared two thermosensitive hydrogels, lactobionic acid-modified chitosan/chitosan/β-glycerophosphate thermosensitive hydrogel (hydrogel 1) and its lyophilized powders (hydrogel 2), characterized their physicochemical properties and evaluated their performance in ESD experiments on large animals, by comparing with the commonly used normal saline (NS) and glycerin fructose (GF). These hydrogels showed good low-temperature fluidity; their viscosities at 4 °C were 92.2 mPa.s and 26.9 mPa.s, respectively. The hydrogels provided significantly better viscoelastic properties than NS and GF. The relaxation moduli of hydrogels were higher than those of NS and GF when the strains were 1 %, 5 %, and 10 %. The hydrogels can be maintained for seven days, even at pH 1, after which they degrade entirely. In pig model experiments, we performed submucosal injection and ESD procedures in the stomach and esophagus. The cushion height produced by the hydrogels was higher than those of NS and GF 30 min after injection. The ESD operation time for hydrogels was significantly shorter. Postoperative wound observation and histological analysis showed that the hydrogels promoted wound healing. The two hydrogels differed in fluidity, viscoelasticity, and other properties, which makes it possible to select the hydrogels according to the size and location of the lesion during ESD operation, and hydrogel 2 may be more suitable for use in lengthier procedures. In general, the hydrogels showed good performance, facilitated the intraoperative operation of ESD, shorten the operation time and promoted wound healing, which is of great significance for reducing the complications and reducing the threshold of ESD operation and further promoting the popularity of ESD.

Comparison between a novel core knife and the conventional IT knife 2 for endoscopic submucosal dissection of gastric mucosal lesions

BACKGROUND/AIMS

Few studies have compared the performances of endoscopic knives. This study aimed to compare the therapeutic outcomes of a novel core knife and the conventional IT knife 2 for endoscopic submucosal dissection (ESD) of gastric mucosal lesions.

METHODS

This prospective, non-inferiority trial included patients diagnosed with gastric adenoma or early-stage adenocarcinoma at Keimyung University Dongsan Hospital between June and November 2020. The patients were randomly assigned to either the core knife or the IT knife 2 group. The operators and assistants scored the knives' grip convenience and cutting abilities.

RESULTS

A total of 39 patients were enrolled (core knife group, 20 patients; IT knife 2 group, 19 patients). There were no significant between-group differences in operator-assessed grip convenience (9.600 vs. 9.526, p=0.753), cutting ability (9.600 vs. 9.105, p=0.158), or assistant-assessed grip convenience (9.500 vs. 9.368, p=0.574).

CONCLUSION

The core knife achieved therapeutic outcomes that were comparable to those of the IT knife 2 for ESD of gastric mucosal lesions.

The future of endoscopic resection for early gastric cancer

Endoscopic resection for early gastric cancer is recommended when the risk of lymph node metastasis is negligible and should be performed through submucosal dissection due to well-established short- and long-term results. To overcome technical difficulties and decrease adverse events some techniques have been studied. This review outlines current strategies for improving patient selection and highlights innovative techniques that help minimize adverse events. Moreover, we discuss how to improve management after curative and noncurative resections.

The Efficacy of a Novel Type of Integrated Knife for Endoscopic Submucosal Dissection in Early Gastric Cancer

Background/Aims: This study aimed to compare the efficacy of a recently developed clear-cut knife with that of widely used knives for endoscopic submucosal dissection (ESD) in early gastric cancer (EGC).Materials and Methods: Data were collected retrospectively from the National Health Insurance Service Ilsan Hospital between May 2017 and April 2019. The study included 105 patients (108 lesions) with EGC who underwent ESD. Fifty-six EGCs were dissected using an insulation-tipped diathermic knife in combination with a needle knife, while 52 EGCs were dissected using a clear-cut knife, a single device with an integrated needle and an insulated-tipped knife. Oncologic outcomes and technical success were compared between the two groups.Results: The distribution of the tumor locations, composition of the undifferentiated types of EGCs, and the size of EGCs (14.3±8.0 vs. 16.6±7.3 mm; P=0.130) were not significantly different between the groups. The complete (98.2% vs. 94.2%; P=0.273) and curative (87.5% vs. 88.5%; P=0.878) resection rates were not statistically different. Furthermore, no significant difference between the total procedure times (39±34.1 vs. 35.7±20.1 minutes; P=0.554), areas of the dissected specimen (858.6±406.5 vs. 980.3±393.8 mm2; P=0.119) and dissected areas per minute (32.4±17.9 vs. 35.5±16.2 mm²/min; P=0.345) were noted. Regarding complications, the overall perforation rates (3.6% vs. 4.0%) and bleeding rates (3.6% vs. 8.0%) were not statistically different.Conclusions: The newly developed clear-cut knife is as useful as the combination of classical knives for ESD in EGC.

The application of endoscopic loop ligation in defect repair following endoscopic full-thickness resection of gastric submucosal tumors originating from the muscularis propria layer

OBJECTIVE

We sought to investigate the clinical efficacy and safety of a novel endoscopic closure technique in repairing gastric wall defects after endoscopic full-thickness resection (EFTR) of gastric submucosal tumors (SMTs) originating from the muscularis propria layer.

METHODS

From December 2016 to December 2019, patients with gastric submucosal tumors were enrolled and clinicopathological data were collected. All SMTs were resected by EFTR and gastric wall defects were closed using a novel endoscopic closure technique. The feasibility, efficacy, and safety were evaluated.

RESULTS

A total of 21 patients with gastric SMTs were included in this study. Among the included SMTs, 15 tumors were located in the fundus of the stomach, and 6 were located in the upper body of the stomach. The average size of the lesions was 2.3 cm (range: 1.9-2.5 cm). All patients underwent EFTR and the gastric wall defect was closed by endoscopic closure. The average endoscopic closure time was 9 min (range: 7-15 min) and the average hospitalization stay length was five days (range: 4-6 days). One patient developed abdominal pain on the first day after the procedure and their body temperature increased; he received treatments such as anti-infection, antacid, and gastrointestinal decompression and was cured and discharged after 4 days. No instance of delayed bleeding, postoperative gastrointestinal fistula, or abdominal infection occurred. No case was transferred to surgery. The postoperative pathology profile included 18 stromal tumors and 3 leiomyomas. During the follow-up period (6-24 months), no case of residual or recurrence was recorded.

CONCLUSION

The described endoscopic loop ligation technique is feasible, effective, and safe for repairing gastric wall defects after EFTR for gastric submucosal tumors originating from the muscularis propria layer.

Chitosan thermosensitive hydrogels based on lyophilizate powders demonstrate significant potential for clinical use in endoscopic submucosal dissection procedures

The goal of this study was to develop intraoperative biomaterials for use in endoscopic submucosal dissection (ESD) procedures that are stable during storage, easy to use, and effective in clinical practice. Therefore, injectable thermosensitive hydrogels were developed based on lactobionic acid-modified chitosan/chitosan/β-glycerophosphate (CSLA/CS/GP) hydrogel lyophilizate powders, and their properties were compared with original hydrogels that had not been freeze-dried. The results indicated that the lyophilizate powders retained their thermosensitive properties, and gels could be formed within 5 min at 37 °C. Compared to the original hydrogels, the injectability of the hydrogels derived from lyophilizate powders increased significantly. These novel materials maintained their original porous network lamellar structure but exhibited improved mechanical strength and tissue adhesion. Their application with L929 and GES-1 cells revealed that the lyophilizate powder hydrogels demonstrated good cytocompatibility and clearly protected the cells in an acidic environment. The results of submucosal injection experiments involving porcine stomach tissue indicated that the heights of the cushions created by CSLA/CS/GP lyophilizate powder hydrogels lasted longer than those generated with normal saline. The thermosensitive hydrogels based on lyophilizate powders may contribute to practical clinical applications involving ESD, and may also have potential value for other applications in the digestive tract.

Lactobionic acid-modified chitosan thermosensitive hydrogels that lift lesions and promote repair in endoscopic submucosal dissection

To develop a biomaterial to lift the lesion and promote wound healing in endoscopic submucosal dissection (ESD), we used lactobionic acid (LA) to improve the water solubility of chitosan (CS) and prepared a new three-phase hydrogel system with lactobionic acid-modified chitosan/chitosan/β-glycerophosphate (CSLA/CS/GP). The results indicated that the hydrogel retains temperature-sensitive properties, and CSLA obviously improved the low-temperature fluidity of the hydrogel precursor solution, enabling injection of the hydrogel by endoscopic needle. The mechanical strength and bio-adhesion of the hydrogels were also improved by the addition of CSLA and the hydrogels could be maintained in acidic environment for a few days and exhibit greater protection of cells. The CSLA/CS/GP hydrogels show good cytocompatibility. The heights of cushions elevated by CSLA/CS/GP hydrogels remained ∼ 60 % 2 h post-injection in porcine stomach models. Given the unique characteristics of these materials, the CSLA/CS/GP thermo-sensitive hydrogel is a promising intraoperative biomaterial in ESD.

Snare Tip Is an Alternative Tool for Colorectal Endoscopic Submucosal Dissection

BACKGROUND

Colorectal endoscopic submucosal dissection is typically performed by specialized knife, such as a dual knife. However, it is not covered by Taiwan's National Health Insurance. In the literature review, using a traditional snare tip for endoscopic submucosal dissection has been reported for stomach lesions only.

OBJECTIVE

The purpose of this study was to evaluate the outcomes of colorectal endoscopic submucosal dissection using a snare tip.

DESIGN

We retrospectively reviewed the clinical using of a snare tip compared with a dual knife for colorectal endoscopic submucosal dissection. Postoperative short- and long-term outcomes were investigated after the procedure.

SETTINGS

This study was conducted at a single tertiary care institution.

PATIENTS

Patients who could not afford the expense of a specialized knife were included.

MAIN OUTCOME MEASURES

Dissection time, dissection speed, and perioperative complications were used for short-term outcome measurement. Recurrence-free rate was used for long-term outcome measurement.

RESULTS

Twenty-one lesions were in the snare tip group and 57 lesions in the dual knife group. The outcomes, including rate of en bloc resection, complication, local recurrence, and recurrence-free interval, between the 2 groups were similar. The mean resected specimen diameter in the dual knife group is larger than the snare tip group (p = 0.041). The dissection time of the snare tip group was shorter than the dual knife group (p = 0.025). However, the dissection speed was significantly slower in the snare tip group than in the dual knife group (p = 0.008).

LIMITATIONS

This study was a retrospective and single doctor chart review in nature with a limited patient number.

CONCLUSIONS

The snare tip is an alternative tool for colorectal endoscopic submucosal dissection in a selected population without the support of specialized knives, such as the dual knife. Although the dissection speed is slower using a snare tip, it is still a recommended technique for developing country or low-income patients.

Diode Laser-Can It Replace the Electrical Current Used in Endoscopic Submucosal Dissection?

Background/Aims

A new medical fiber-guided diode laser system (FDLS) is expected to offer high-precision cutting with simultaneous hemostasis. Thus, this study aimed to evaluate the feasibility of using the 1,940-nm FDLS to perform endoscopic submucosal dissection (ESD) in the gastrointestinal tract of an animal model.

Methods

In this prospective animal pilot study, gastric and colorectal ESD using the FDLS was performed in ex vivo and in vivo porcine models. The completeness of en bloc resection, the procedure time, intraprocedural bleeding, histological injuries to the muscularis propria (MP) layer, and perforation were assessed.

Results

The en bloc resection and perforation rates in the ex vivo study were 100% (10/10) and 10% (1/10), respectively; those in the in vivo study were 100% (4/4) and 0% for gastric ESD and 100% (4/4) and 25% (1/4) for rectal ESD, respectively. Deep MP layer injuries tended to occur more frequently in the rectal than in the gastric ESD cases, and no intraprocedural bleeding occurred in either group.

Conclusions

The 1,940-nm FDLS was capable of yielding high en bloc resection rates without intraprocedural bleeding during gastric and colorectal ESD in animal models.

Long-Term Outcomes and Prognostic Factors of Endoscopic Submucosal Dissection for Early Gastric Cancer in Patients Aged ≥75 Years

Simple Summary

The number of elderly patients with early gastric cancer (EGC) who meet the indications for endoscopic submucosal dissection (ESD) is increasing. Since elderly patients have more comorbidities, and lower life expectancy than younger patients, special considerations to establish treatment strategies according to prognosis is needed. We investigate overall survival and risk factors related to survival after ESD in these patients. During the follow-up, the 3-, 5-, and 10-year overall survival was 91.2%, 83.5%, and 54.5%, respectively. Smoking, history of cancer of other organs, neutrophil to lymphocyte ratio > 1.6, Charlson comorbidity index ≥ 3, and presence of lymphovascular invasion were independent five risk factors for poor overall survival. The long-term outcome of ESD was poorer in elderly patients with risk factors than in those without. These prognostic factors can also be useful in deciding whether to recommend additive surgery and a close follow-up after non-curative endoscopic treatment in the elderly patients.

Abstract

Background and Aims: The number of elderly patients with early gastric cancer (EGC) who meet the indications for endoscopic submucosal dissection (ESD) is increasing. We aimed to evaluate the clinical outcomes and prognostic factors of overall survival (OS) in elderly patients undergoing ESD for EGC. Methods: Between January 2006 and December 2018, 439 patients aged ≥75 years who underwent ESD for EGC were analyzed. The clinical outcomes and prognosis were evaluated, and independent risk factors for OS were identified. Results: The mean patient (302 men, 137 women) age was 78.3 (range 75–92) years. En bloc, R0, and curative resections were achieved in 96.8%, 90.7%, and 75.6%, respectively, without severe adverse events. During the follow-up (median 54.2 (range 4.0–159.6) months), 86 patients died (three of gastric cancer). The 3-, 5-, and 10-year OS was 91.2%, 83.5%, and 54.5%, respectively, and the 3-, 5-, and 10-year cancer related survival rate were 99.7%, 99.1% and 97.5%, respectively. In multivariate analysis, smoking, history of cancer of other organs, NLR > 1.6, Charlson comorbidity index ≥ 3, and presence of lymphovascular invasion (hazard ratio = 3.96, 1.78, 1.83, 1.83, and 2.63, respectively, all p < 0.05) were independent five risk factors for poor OS. The high-risk group (≥3 risk factors) showed a significantly lower OS than the low-risk group (<2 risk factors) (p < 0.001). Conclusions: The five factors could be useful in predicting the long-term prognosis of elderly ESD patients or deciding the therapeutic approaches in case of non-curative resection.

Determining the Safety and Effectiveness of Electrocautery Enhanced Scissors for Peroral Endoscopic Myotomy (with Video)

BACKGROUND/AIMS

Peroral endoscopic myotomy (POEM) has recently come to the forefront in the management of achalasia. We aimed to analyze the efficacy and safety of the use of electrocautery enhanced scissors (EES) for POEM.

METHODS

This retrospective cohort study prospectively collected the data of all adult patients (aged ≥18 years) with normal foregut anatomy who underwent POEM using EES. The patients' baseline characteristics and procedure details (time, tunnel length, myotomy length, depth, and location) were recorded. The primary outcome was clinical success (3-month post-procedure Eckardt score of ≤3). The secondary outcomes were technical success and adverse events. A paired Student's t-test was performed.

RESULTS

Fifteen patients were included in this study. The technical success rate of myotomy using EES was 100%. Fellows participated in the myotomy in all cases. The clinical success rate was 93.3% (14/15). The mean pre-Eckardt score was 5.4±2.5, while the mean post-Eckardt score was 1.3±1.3, which indicated a significant improvement (p≤0.0001). The most common treatment-related adverse events were post-procedure pain (4, 26.7%) and symptomatic reflux disease (4, 26.7%).

CONCLUSION

In the largest series to date on the use of EES in POEM, we demonstrated that this technique has both technical and clinical efficacy as well as an excellent safety profile.

Review on colorectal endoscopic submucosal dissection focusing on the technical aspect

BACKGROUND

Endoscopic submucosal dissection (ESD) enables removal of broad-based colorectal polyps or lateral spreading tumors with a higher rate of en bloc resection and a lower risk of local recurrence. However, it is technically demanding. Over the past 20 years, various equipment and innovative techniques have been developed to reduce the difficulty of ESD. The information in the literature is scattered. Our aim is to provide a comprehensive review on the setup and technical aspects of colorectal ESD.

METHODS

We searched the PubMed database and systemically reviewed all original and review articles related to colorectal ESD. Further manual search according to reference lists of identified articles were done. The selected articles were categorized and reviewed. Original figures were created to help readers understand some of the ESD techniques.

RESULTS

A total of 216 articles were identified, in which 25 of them were review articles and 191 of them were original articles. They were categorized and reviewed. An in-depth appraisal of the setting, equipment, and technical aspects of colorectal ESD was performed.

CONCLUSIONS

Although ESD is a technically demanding procedure that requires expert endoscopic skills, it can be mastered. With good peri-procedural preparation, sufficient knowledge of the equipment, and thorough understanding of the useful endoscopic tricks and maneuvers, colorectal ESD can be performed smoothly and safely.