The suture-pulley method for endolumenal triangulation in endoscopic submucosal dissection

Endoscopic mucosal resection and endoscopic submucosal dissection with an external additional working channel (EMR+ and ESD+) are equivalent to using a double-channel endoscope: a systematic evaluation in a porcine ex vivo model

BACKGROUND AND AIMS

With an external additional working channel (AWC) endoscopic mucosal resection (EMR) as well as endoscopic submucosal dissection (ESD) can be extended to techniques termed "EMR+" and "ESD+." These novel techniques are systematically compared to EMR and ESD under the use of a double-channel endoscope (DC).

METHODS

Our trial was conducted prospectively in a pre-clinical porcine animal model (EASIE-R simulator) with standardized gastric lesions measuring 3 or 4 cm.

RESULTS

EMR+ and EMR DC showed both good results for 3 cm lesions with no adverse events and an en bloc resection rate of 73.33% (EMR+) and 60.00% (EMR DC, p = 0.70). They came to their limits in 4 cm lesions with muscularis damages of 20.00% (EMR+), 13.33% (EMR DC, p ≥ 0.99) and decreasing en bloc resection rates of 60.00% (EMR+) and 46.67% (EMR DC, p = 0.72). ESD+ and ESD DC were both reliable concerning en bloc resection rates (100% in all groups) and adverse events (0.00% in 3 cm lesions, 12.50% muscularis damages in both ESD+ and ESD DC in 4 cm lesions). Resection time was slightly shorter in all groups with the AWC compared to DC although only reaching significance in 3 cm ESD lesions (p < 0.05*).

CONCLUSIONS

With the AWC, a standard endoscope can easily be transformed to double-channel functionality. We could show that EMR+ and ESD+ are non-inferior to EMR and ESD under the use of a double-channel endoscope. Consequently, the AWC presents an affordable alternative to a double-channel endoscope for both EMR and ESD.

Endoscopic submucosal dissection with an additional working channel (ESD+): a novel technique to improve procedure time and safety of ESD

Background and aims

A new external additional working channel (AWC) was recently introduced by which endoscopic submucosal dissection (ESD) can be converted to a technique termed “ESD+ ”. We aim to systematically evaluate this novel technique in flat gastric lesions and compare it to classical ESD.

Methods

The study was prospectively conducted in a pre-clinical ex vivo animal model (EASIE-R simulator) with porcine stomachs. Prior to intervention, we set standardized lesions measuring 3 cm or 4 cm in antegrade as well as in retrograde positions.

Results

Overall, 64 procedures were performed by an experienced endoscopist. Both techniques were reliable and showed en bloc resection rates of 100%. Overall, ESD+ reduced time of procedure compared to ESD (24.5 vs. 32.5 min, p = 0.025*). Particularly, ESD+ was significantly faster in retrograde lesions with a median of 22.5 vs. 34.0 min in 3 cm retrograde lesions (p = 0.002*) and 34.5 vs. 41.0 min (p = 0.011*) in 4 cm retrograde lesions. There were 0 perforations with both techniques. In ESD+ , 1 muscularis damage occurred (3.13%) compared to 6 muscularis damages with ESD (18.75%, p = 0.045*).

Conclusions

By its grasp-and-mobilize technique, ESD+ allows potentially faster and safer resections of flat gastric lesions compared to conventional ESD in an ex vivo porcine model. The potential advantages of ESD+ in terms of procedure time may be particularly relevant for difficult lesions in retrograde positions.

Electronic supplementary material

The online version of this article (10.1007/s00464-020-07808-w) contains supplementary material, which is available to authorized users.

The Development of the Overstitch System and Its Potentials

Endoscopic suturing device for flexible endoscopy was conceptualized by Apollo Group in collaboration with Olympus Optical Ltd. The first modification of suturing device for flexible endoscopy (Eagle Claw) was manufactured by Olympus engineers and extensively used by members of Apollo Group in numerous bench-top experiments on isolated pig stomachs and in live porcine model. The suturing system for flexible endoscopy in humans (Overstitch) was cleared for general clinical use in the United States in 2008. The latest model is compatible with more than 20 single-channel flexible endoscopes with diameters ranging from 8.8 mm to 9.8 mm made by major endoscope manufacturers.

EMR + with the AWC improves endoscopic resection speed compared to ESD: a porcine ex-vivo pilot study

INTRODUCTION

To improve resection speed and to reach higher en bloc resection rates in lesions ≥ 2 cm, a novel grasp and snare EMR technique termed "EMR+", accomplished by an additional working channel (AWC), was developed. Its use compared to endoscopic submucosal dissection (ESD) is evaluated for the first time.

MATERIAL AND METHODS

We prospectively conducted a randomized pre-clinical ex-vivo pilot study in explanted porcine stomachs for the comparison of EMR + with classical ESD of mucosal-based lesions. Prior to intervention, we set flat lesions with a standardized size of 3 × 3 cm.

RESULTS

The median time of procedure was significantly shorter in the EMR + group (median 10.5 min, range 4.4-24 min) than in the ESD group (median 32 min, range 14-61.6 min, p < .0001). The rate of en bloc resection was significantly lower in the EMR + group (38 % vs. 95 %) (p < .0001). Nevertheless, an improvement in the learning curve for EMR + was achieved after the first 12 procedures, with a subsequent en bloc resection rate of 100 %.

CONCLUSIONS

EMR + could improve the efficiency of mucosal resection procedures. Initial experience demonstrates a higher and satisfactory en bloc resection rate after going through the learning curve of EMR+.

Suture pulley countertraction method reduces procedure time and technical demand of endoscopic submucosal dissection among novice endoscopists learning endoscopic submucosal dissection: a prospective randomized ex vivo study

BACKGROUND AND AIMS

The lack of reliable countertraction in endoscopic submucosal dissection (ESD) contributes to its technical demand and increased procedure time. We aimed to prospectively evaluate the efficacy of the suture pulley countertraction method in endoscopists new to both suturing and ESD.

METHODS

Two 30-mm circular lesions were created in an ex vivo porcine stomach model. Endoscopists considered novices for both endoscopic suturing and ESD were randomized to either traditional or suture pulley ESD first and performed ESD using each technique. Procedure time was recorded including time of circumferential incision, suture pulley placement, and submucosal dissection. After completion of each ESD, participants graded the difficulty of the procedure using the National Aeronautical and Space Administration (NASA) Task Load Index.

RESULTS

Thirteen participants (8 fellows, 5 attendings) completed the study using both methods. Mean total procedure time was shorter using suture pulley ESD compared with traditional ESD (26.7 ± 7.3 vs 59.4 ± 20.4 minutes, P < .001). The suture pulley required a mean 6.2 ± 2.1 minutes to place. Submucosal dissection time was shorter using suture pulley ESD compared with traditional ESD (8.4 ± 2.9 vs 47.2 ± 16.3 minutes, P < .001). All 7 individual indices and total score on the NASA Task Load Index were significantly improved using the suture pulley ESD method (P < .001).

CONCLUSIONS

The suture pulley countertraction method significantly decreases procedure time and technical demand of ESD among endoscopists at all skill levels who are new to ESD. The results of this study have potential implications for ESD training in the United States.

Endoscopic management of colonic perforations: clips versus suturing closure (with videos)

BACKGROUND AND AIMS

Perforation during colonoscopy remains the most worrisome adverse event and usually requires urgent surgical rescue. The aim of this study was to evaluate the feasibility and effectiveness of endoscopic closure of full-thickness colonic perforations.

METHODS

We performed a retrospective analysis of all consecutive patients with endoscopically closed colonic perforations over the past 6 years (2009-2014). Colonic perforations were closed by using endoscopic clips or an endoscopic suturing device. Most patients were admitted for treatment with intravenous antibiotics and kept on bowel rest. If their clinical condition deteriorated, urgent surgery was performed. If patients remained stable, oral feeding was resumed, and patients were discharged with subsequent clinical and endoscopic follow-up.

RESULTS

Twenty-one patients had iatrogenic colonic perforations closed with an endoscopic suturing device or endoscopic clips during the study period. Primary closure of a colonic perforation was performed with endoscopic clips in 5 patients and sutured with an endoscopic suturing device in 16 patients. All 5 patients after clip closure had worsening of abdominal pain and required laparoscopy (4 patients) or rescue colonoscopy with endoscopic suturing closure (1 patient). Two patients had abdominal pain after endoscopic suturing closure, but diagnostic laparoscopy confirmed complete and adequate endoscopic closure of the perforations. The other 15 patients did not require any rescue surgery or laparoscopy after endoscopic suturing. The main limitation of our study is its retrospective, single-center design and relatively small number of patients.

CONCLUSION

Endoscopic suturing closure of colonic perforations is technically feasible, eliminates the need for rescue surgery, and appears more effective than closure with hemostatic endoscopic clips.

New endoscopic platform for endoluminal en bloc tissue resection in the gastrointestinal tract (with videos)

BACKGROUND

Endoscopic removal of gastrointestinal tract lesions is increasingly popular around the world. We evaluated feasibility, safety, effectiveness, and user learning curve of new endoscopic platform for complex intraluminal interventions.

METHODS

A novel system, consisting of expandable working chamber with two independent instrument guides (LIG), was inserted into colon. Simulated colonic lesions were removed with endoscopic submucosal (ESD) and submuscular (ESmD) dissection.

RESULTS

In all nine in vivo models, an intraluminal chamber and its dynamic tissue retractors (via LIG) provided a stable working space with excellent visualization and adequate access to target tissue. Endoscopic platform facilitated successful completion of 11 en bloc ESDs (mean size 43.0 ± 11.3 mm, mean time 46.3 ± 41.2 min) and eight ESmD (mean size 50.0 ± 14.1 mm, mean time 48.0 ± 21.2 min). The learning curve for ESD using this platform demonstrated three phases: rapid improvement in procedural skills took place during the first three procedures (mean ESD time 98.7 ± 40.0 min). A plateau phase then occurred (procedures 4-7) with mean procedure time 42.0 ± 13.4 min (p = 0.04), followed by another sharp improvement in procedural skills (procedures 8-11) requiring only 16.3 ± 11.4 min (p = 0.03) to complete ESD. Especially dramatic (p = 0.002) was the time difference between the first three procedures (mean time 98.7 ± 40.0 min) and subsequent eight procedures (mean time 29.1 ± 17.9 min).

CONCLUSIONS

A newly developed endoscopic platform provides stable intraluminal working space, dynamic tissue retraction, and instrument triangulation, improving visualization and access to the target tissue for safer and more effective en bloc endoscopic submucosal and submuscular dissection. The learning curve for ESD was markedly facilitated by this new endoscopic platform.

East Meets West-A Novel Steerable Grasper to Facilitate Gastric Endoscopic Submucosal Dissection (ESD): Randomized Comparative Study in a Porcine Model

BACKGROUND

Endoscopic submucosal dissection (ESD) is challenging because of the limited ability of conventional endoscopic tools to achieve adequate traction. We have recently used a novel steerable grasper (SG; ANUBIS grasper, Karl Storz, Tüttlingen, Germany) with intuitive manipulating handles to lift up the mucosa. The aim of this study is to evaluate the efficacy of the assistance of the SG in a porcine acute model.

MATERIALS AND METHODS

A total of 36 gastric ESDs were performed in 12 swine (3 ESDs/pig), at the antrum, greater curvature of the gastric body, and cardia. Pigs were randomly assigned to the SG group (n = 6) or to the control group (n = 6). ESD steps included the following: scoring the area, submucosal injection, and precut and submucosal dissection with or without SG assistance. Outcomes measured were as follows: dissection time, dissection speed, size of specimen, completeness of dissection (all marks included in the specimen), en bloc dissection, and complications.

RESULTS

Overall mean dissection time was 18.6 ± 7.56 versus 29 ± 18.14 minutes (P = .032), and mean dissection speed was 94.74 ± 39.74 mm(2)/min versus 65.41 ± 39.5 mm(2)/min (P = .033) in the SG and control groups, respectively. Mean size of the specimen was 1451.4 ± 549.2 mm(2) in the SG group and 1615.3 ± 605.9 in the control group. Complete and en bloc dissections were achieved in all cases. One deep muscular injury occurred in the control group (gastric body).

CONCLUSION

The ANUBIS grasper is a user-friendly, effective, and safe tool to achieve adequate traction and exposure of the ESD plane in the pig model.

Facilitating endoscopic submucosal dissection: the suture-pulley method significantly improves procedure time and minimizes technical difficulty compared with conventional technique: an ex vivo study (with video)

BACKGROUND

The lack of countertraction in endoscopic submucosal dissection (ESD) results in increased technical demand and procedure time. Although the suture-pulley method for countertraction has been reported, its effectiveness compared with the traditional ESD technique remains unclear.

OBJECTIVE

To objectively analyze efficacy of countertraction using the suture-pulley method for ESD.

DESIGN

Prospective ex vivo animal study.

SETTING

Animal laboratory.

INTERVENTIONS

Twenty simulated gastric lesions were created in porcine stomachs by using a standard circular template 30 mm in diameter. In the control arm (n = 10), ESD was performed by using the standard technique. In the suture-pulley arm (N = 10), a circumferential incision was made, and an endoscopic suturing device was used to place the suture pulley.

MAIN OUTCOME MEASUREMENTS

The primary outcome of this study was total procedure time.

RESULTS

The median total procedure time with the suture-pulley method was significantly shorter than the traditional ESD technique (median, 25% to 75%, interquartile range [IQR]: 531 seconds [474.3-549.3 seconds] vs 845 seconds [656.3-1547.5 seconds], P < .001). The median time (IQR) for suture-pulley placement was 160.5 seconds (150.0-168.8 seconds). Although there was a significantly longer procedure time for proximal versus middle/lower stomach lesions with traditional ESD (median, 1601 seconds; IQR, 1547.5-1708.8 seconds vs median, 663 seconds; IQR, 627.5-681.8 seconds; P = .01), there was no significant difference in procedure time for lesions of various locations when using the suture-pulley method. Compared with traditional ESD, the suture-pulley method was less demanding in all categories evaluated by the NASA Task Load Index.

LIMITATIONS

Ex vivo study.

CONCLUSIONS

The suture-pulley method facilitates direct visualization of the submucosal layer during ESD and significantly reduces procedure time and technical difficulty. In addition, the benefit of the suture-pulley method was seen for both simple and more complicated ESDs.

Endoscopic submucosal dissection with a novel traction method using a steerable grasper: a feasibility study in a porcine model

INTRODUCTION

Endoscopic submucosal dissection (ESD) is a technically challenging procedure in which complications and operative times depend on the operator's expertise as well as on the location and size of the lesion. Good visualization of the submucosal dissection plane is essential to perform a safe and effective ESD.

OBJECTIVES

To evaluate the feasibility, efficacy, and safety of a novel traction method using an over-the-scope steerable grasper to improve the exposure of the dissection plane during gastric ESD.

RESULTS

A total of 24 ESDs were performed without any complications in various locations of porcine stomachs, including antrum, gastric body, and cardia. En bloc complete resections were achieved in all cases. The mean specimen size was 44.92 ± 8.30 mm, mean total procedure time was 29.17 ± 11.27 minutes, and mean dissection time was 15.08 ± 7.21 minutes. The optimal dissection plane could be obtained by controlling the grasper in all cases.

CONCLUSIONS

Technical feasibility, efficacy, and safety of the over-the-scope steerable grasper technique were demonstrated in order to provide dynamic and controlled traction during ESD at different locations of porcine stomachs.

Endoluminal surgical triangulation: overcoming challenges of colonic endoscopic submucosal dissections using a novel flexible endoscopic surgical platform: feasibility study in a porcine model

BACKGROUND

Colonic endoscopic submucosal dissection (ESD) is challenging as a result of the limited ability of conventional endoscopic instruments to achieve traction and exposure. The aim of this study was to evaluate the feasibility of colonic ESD in a porcine model using a novel endoscopic surgical platform, the Anubiscope (Karl Storz, Tüttlingen, Germany), equipped with two working channels for surgical instruments with four degrees of freedom offering surgical triangulation.

METHODS

Nine ESDs were performed by a surgeon without any ESD experience in three swine, at 25, 15, and 10 cm above the anal verge with the Anubiscope. Sixteen ESDs were performed by an experienced endoscopist in five swine using conventional endoscopic instruments. Major ESD steps included the following for both groups: scoring the area, submucosal injection of glycerol, precut, and submucosal dissection. Outcomes measured were as follows: dissection time and speed, specimen size, en bloc dissection, and complications.

RESULTS

No perforations occurred in the Anubis group, while there were eight perforations (50 %) in the conventional group (p = 0.02). Complete and en bloc dissections were achieved in all cases in the Anubis group. Mean dissection time for completed cases was statistically significantly shorter in the Anubis group (32.3 ± 16.1 vs. 55.87 ± 7.66 min; p = 0.0019). Mean specimen size was higher in the conventional group (1321 ± 230 vs. 927.77 ± 229.96 mm(2); p = 0.003), but mean dissection speed was similar (35.95 ± 18.93 vs. 23.98 ± 5.02 mm(2)/min in the Anubis and conventional groups, respectively; p = 0.1).

CONCLUSIONS

Colonic ESDs were feasible in pig models with the Anubiscope. This surgical endoscopic platform is promising for endoluminal surgical procedures such as ESD, as it is user-friendly, effective, and safe.