Feasibility and safety of third-space endoscopic full-thickness resection in ex vivo and in vivo porcine models

Abstract Background and study aims Endoscopic full-thickness resection (EFTR) involves several technical issues that need to be addressed. We devised a novel technique termed third-space EFTR and investigated its feasibility and safety in animal models. Methods Third-space EFTR was performed in three isolated porcine stomachs (ex vivo) and four live pigs (in vivo, 1-week survival). The technique involved a circumferential mucosal incision, submucosal tunnelling on the proximal side, endoscopic suturing of the surrounding mucosa, a circumferential seromuscular incision in the submucosal tunnel, transoral retrieval and entry site closure of the tunnel. The technical outcomes were investigated. Results In the ex vivo study, the procedure was successfully completed with R0 resection. In the in vivo study, the procedure was completed in all pigs; however, R0 resection failed in one pig owing to snaring resection. All pigs survived without severe adverse events. Conclusions Our findings indicate that third-space EFTR is feasible and safe. This technique may be useful as a minimally invasive endoscopic option for reliable treatment of small gastric submucosal tumours.

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Endoscopic full-thickness resection of gastric tumors using a novel grasp-and-snare technique: feasibility in ex vivo and in vivo porcine models

Endoscopy ◽

10.1055/s-2008-1077587 ◽

2008 ◽

Vol 40 (11) ◽

pp. 931-935 ◽

Cited By ~ 12

Author(s):

B. Elmunzer ◽

J. Trunzo ◽

J. Marks ◽

B. Poulose ◽

A. Chak ◽

...

Keyword(s):

Ex Vivo ◽

Full Thickness ◽

Gastric Tumors ◽

Endoscopic Full Thickness Resection

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Sealed endoscopic full-thickness resection for gastric cancer: a pilot study in an ex vivo and in vivo porcine model

Endoscopy International Open ◽

10.1055/a-0777-1954 ◽

2019 ◽

Vol 07 (01) ◽

pp. E36-E42 ◽

Cited By ~ 1

Author(s):

Hidekazu Kitakata ◽

Tohru Itoh ◽

Shinichi Kinami ◽

Ken Kawaura ◽

Kazu Hamada ◽

...

Keyword(s):

Ex Vivo ◽

Abdominal Cavity ◽

Gastric Wall ◽

Layer By Layer ◽

Full Thickness ◽

Endoscopic View ◽

In Vivo Experiment ◽

Endoscopic Full Thickness Resection ◽

Time Required

Abstract Background and study aims Endoscopic full-thickness resection (EFTR) is a useful procedure that allows minimal resection of the gastric wall because the tumor can be located endoscopically. However, the procedure carries a risk of peritoneal infection or dissemination. Thus, we devised a new EFTR technique in which the serosa is sealed using a silicone sheet to prevent the escape of gastric juice. Materials and methods Three whole stomachs were harvested from pigs for an ex vivo experiment, and seven pigs were used for an in vivo experiment. In both experiments, silicone sheets and gauze were pasted to the serosa using a fibrinogen-thrombin solution. A seromuscular incision was then made endoscopically using a HookKnife. We then evaluated whether stomach collapse could be prevented using this technique. Furthermore, the method was compared with conventional laparoscopic-assisted EFTR (LA-EFTR) in terms of resection time and quality of endoscopic view. Results In the ex vivo experiment, stomach collapse was suppressed and the seromuscular layer could be incised layer by layer. In the in vivo experiment, the time required for seromuscular incision with the new EFTR technique was significantly shorter than that with the conventional method. All layers of the stomach were smoothly resected under good endoscopic view. Conclusions Sealed EFTR is a potentially useful technique for the minimally invasive resection of gastric tumor. All layers of the stomach could be incised while confirming the incision line from the inside of the stomach and avoiding exposure of the tumor to the abdominal cavity.

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Endoscopic full thickness resection vs. transanal endoscopic microsurgery for local treatment of rectal neuroendocrine tumors - a retrospective analysis

International Journal of Colorectal Disease ◽

10.1007/s00384-020-03800-x ◽

2020 ◽

Author(s):

Markus Brand ◽

Stanislaus Reimer ◽

Joachim Reibetanz ◽

Sven Flemming ◽

Marko Kornmann ◽

...

Keyword(s):

Neuroendocrine Tumors ◽

Transanal Endoscopic Microsurgery ◽

Local Treatment ◽

University Hospital ◽

R0 Resection ◽

Full Thickness ◽

Resection Rate ◽

En Bloc ◽

Endoscopic Full Thickness Resection ◽

Endoscopic Microsurgery

Abstract Purpose Local treatment of small well-differentiated rectal neuroendocrine tumors (NETs) is recommended by current guidelines. However, although several endoscopic methods have been established, the highest R0 rate is achieved by transanal endoscopic microsurgery (TEM). Since a recently published study about endoscopic full thickness resection (eFTR) showed a R0 resection rate of 100%, the aim of this study was to evaluate both methods (eFTR vs. TEM). Methods We retrospectively analyzed all patients with rectal NET treated either by TEM (1999–2018) or eFTR (2016–2019) in two tertiary centers (University Hospital Wuerzburg and Ulm). We analyzed clinical, procedural, and histopathological outcomes in both groups. Results Twenty-eight patients with rectal NET received local treatment (TEM: 13; eFTR: 15). Most tumors were at stage T1a and grade G1 or G2 (in the TEM group two G3 NETs were staged T2 after neoadjuvant chemotherapy). In both groups, similar outcomes for en bloc resection rate, R0 resection rate, tumor size, or specimen size were found. No procedural adverse events were noted. Mean procedure time in the TEM group was 48.9 min and 19.2 min in the eFTR group. Conclusion eFTR is a convincing method for local treatment of small rectal NETs combining high safety and efficacy with short interventional time.

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Effect of Skin Model on In Vitro Performance of an Adhesive Dermally Applied Microarray Coated with Zolmitriptan

Journal of Pharmaceutics ◽

10.1155/2018/7459124 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5 ◽

Cited By ~ 1

Author(s):

Mahmoud Ameri ◽

Hayley Lewis ◽

Paul Lehman

Keyword(s):

Human Skin ◽

Ex Vivo ◽

Full Thickness ◽

Artificial Membrane ◽

Skin Model ◽

Hydrophobic Membrane ◽

Thickness Skin ◽

In Vitro Performance

Franz cell studies, utilizing different human skin and an artificial membrane, evaluating the influence of skin model on permeation of zolmitriptan coated on an array of titanium microprojections, were evaluated. Full thickness and dermatomed ex vivo human skin, as well as a synthetic hydrophobic membrane (Strat-M®), were assessed. It was found that the choice of model demonstrated different absorption kinetics for the permeation of zolmitriptan. For the synthetic membrane only 11% of the zolmitriptan coated dose permeated into the receptor media, whilst for the dermatomed skin 85% permeated into the receptor. The permeation of zolmitriptan through full thickness skin had a significantly different absorption profile and time to maximum flux in comparison to the dermatomed skin and synthetic model. On the basis of these results dermatomed skin may be a better estimate of in vivo performance of drug-coated metallic microprojections.

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Assessment of a novel cryoablation device for the endovascular treatment of cardiac tachyarrhythmias

SAGE Open Medicine ◽

10.1177/2050312118769797 ◽

2018 ◽

Vol 6 ◽

pp. 205031211876979 ◽

Cited By ~ 5

Author(s):

John M Baust ◽

Anthony Robilotto ◽

Peter Guerra ◽

Kristi K Snyder ◽

Robert G Van Buskirk ◽

...

Keyword(s):

Cardiac Tissue ◽

Ex Vivo ◽

High Heat ◽

In Vivo Studies ◽

Full Thickness ◽

Tissue Model ◽

Model Studies ◽

Technological Developments ◽

Procedural Time

Objectives: Cryoablation is an effective alternative treatment for cardiac arrhythmias offering shortened recovery and reduced side effects. As the use of cryoablation increases, the need for new devices and procedures has emerged. This has been driven by technological limitations including lengthy periods to generate a single lesion (3–5 min), uncertain transmurality, and differential efficacy. Furthermore, due to limited ablation capacity under high heat loads, cryo has had limited success in the treatment of ventricular arrhythmias. To this end, in this study we evaluated a new cryoablation catheter, ICEolate, for the targeted ablation of cardiac tissue. Methods: Performance assessment included calorimetry, freeze zone isothermal distribution characterization and catheter ablation capacity in a submerged, circulating, heat-loaded ex vivo tissue model. A pilot in vivo study was also conducted to assess ablative capacity of the cryocatheter in a fully beating heart. Results: Ex vivo studies demonstrated ice formation at the tip of a cryocatheter within 5 s and a tip temperature of ~−150°C within 10 s. The device repeatedly generated freeze zones of 2 cm × 3 cm in less than 2 min. Tissue model studies revealed the generation of a full thickness (5–10 mm) cryogenic lesion within 1 min with an opposite (transmural) surface temperature of <−60°C under a circulating 37°C heat load. Pilot in vivo studies demonstrated the delivery of an ablative “dose,” producing a continuous full thickness transmural linear lesion in <60 s at both atrial and ventricular sites. Conclusion: These studies suggest that the supercritical nitrogen cryodevice and ICEolate cryocatheter may provide for rapid, effective, controllable freezing of targeted tissue. The ablative power, speed, and directional freeze characteristics also offer the potential of improved safety via a reduction in procedural time compared to current cryoablation devices. These technological developments may open new avenues for the application of cryo to treat other cardiac arrhythmogenic disorders.

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ASGE guideline for endoscopic full-thickness resection and submucosal tunnel endoscopic resection

VideoGIE ◽

10.1016/j.vgie.2019.03.010 ◽

2019 ◽

Vol 4 (8) ◽

pp. 343-350 ◽

Cited By ~ 18

Author(s):

Harry R. Aslanian ◽

Amrita Sethi ◽

Manoop S. Bhutani ◽

Adam J. Goodman ◽

Kumar Krishnan ◽

...

Keyword(s):

Endoscopic Resection ◽

Full Thickness ◽

Submucosal Tunnel ◽

Endoscopic Full Thickness Resection ◽

Submucosal Tunnel Endoscopic Resection

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Endoscopic full-thickness resection of polyps involving the appendiceal orifice: a prospective observational case study

Endoscopy International Open ◽

10.1055/a-0635-0911 ◽

2018 ◽

Vol 06 (09) ◽

pp. E1112-E1119 ◽

Cited By ~ 10

Author(s):

Maxime E.S. Bronzwaer ◽

Barbara A.J. Bastiaansen ◽

Lianne Koens ◽

Evelien Dekker ◽

Paul Fockens

Keyword(s):

Colorectal Polyps ◽

Exclusion Criterion ◽

R0 Resection ◽

Full Thickness ◽

Technical Success ◽

En Bloc ◽

Invasive Approach ◽

Tertiary Referral Center ◽

Endoscopic Full Thickness Resection

Abstract Background and study aims Colorectal polyps involving the appendiceal orifice (AO) are difficult to resect with conventional polypectomy techniques and therefore often require surgical intervention. These appendiceal polyps could potentially be removed with endoscopic full-thickness resection (eFTR) performed with a full-thickness resection device (FTRD). The aim of this prospective observational case study was to evaluate feasibility, technical success and safety of eFTR procedures involving the AO. Patients and methods This study was performed between November 2016 and December 2017 in a tertiary referral center by two experienced endoscopists. All patients referred for eFTR with a polyp involving the AO that could not be resected by EMR due to more than 50 % circumferential involvement of the AO or deep extension into the AO were included. The only exclusion criterion was lesion diameter > 20 mm. Results Seven patients underwent eFTR for a polyp involving the AO. All target lesions could be reached with the FTRD and retracted into the device. Technical success with an endoscopic radical en-bloc and full-thickness resection was achieved in all cases. Histopathological R0 resection was achieved in 85.7 % of patients (6/7). One patient who previously underwent an appendectomy developed a small abscess adjacent to the resection site, which was treated conservatively. Another patient developed secondary appendicitis followed by a laparoscopic appendectomy. Conclusion This small exploratory study suggests that eFTR of appendiceal polyps is feasible and can offer a minimally invasive approach for radical resection of these lesions. However, more safety and long-term follow-up data are needed to evaluate this evolving technique.

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Endoscopic full-thickness resection using an endoluminal-suturing device: a proof-of-concept study

Endoscopy International Open ◽

10.1055/a-0860-5387 ◽

2019 ◽

Vol 07 (11) ◽

pp. E1310-E1315 ◽

Cited By ~ 1

Author(s):

Vincent Huberty ◽

Loulia Leclercq ◽

Martin Hiernaux ◽

Laurine Verset ◽

Charlotte Sandersen ◽

...

Keyword(s):

Suture Line ◽

R0 Resection ◽

Full Thickness ◽

Proof Of Concept ◽

First Case ◽

Gastric Lumen ◽

Virtual Lesion ◽

Endoscopic Full Thickness Resection ◽

Needle Knife ◽

Difficult Situations

Abstract Background and study aims Endoscopic full-thickness resection (EFTR) is used to achieve R0 resection in difficult situations and as a way to overcome the limitations of endoscopic submucosal dissection. Multiple techniques have been described but adequate tools are still under evaluation. In this study, we evaluated the safety and feasibility of non-exposed endoscopic full-thickness resection using a novel endoscopic suturing device. Materials and methods Full-thickness resections of gastric predetermined lesions were performed on five pigs using the Endomina platform. After creating virtual lesion > 20 mm, sutures were placed around it using this triangulation platform. After tightening the knots, the bulging lesion, internalized into the gastric lumen, was cut with a needle knife. Results R0 resections of large lesions (42 to 60 mm) were achieved in all cases. One perforation occurred and prompted us to improve the procedure by shortening the sutures for more maneuverability and reinforcing the suture line before section. Procedure duration dropped by 50 % between the first case and the fourth case. Histological analysis confirmed successful full-thickness resection of all resected specimens. Conclusion EFTR using this triangulation platform seems feasible for lesions > 20 mm. Additional possible improvements were identified to simplify the procedure before moving to human trials.

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Endoscopic full-thickness resection in the colorectum: a single-center case series evaluating indication, efficacy and safety

Endoscopy International Open ◽

10.1055/a-0672-1138 ◽

2018 ◽

Vol 06 (10) ◽

pp. E1227-E1234 ◽

Cited By ~ 5

Author(s):

Krijn Haasnoot ◽

Bas van der Spek ◽

Christof Meischl ◽

Dimitri Heine

Keyword(s):

Colorectal Carcinoma ◽

Adverse Events ◽

R0 Resection ◽

Radical Excision ◽

Full Thickness ◽

Efficacy And Safety ◽

Technical Success ◽

Endoscopic Techniques ◽

T1 Colorectal Carcinoma ◽

Endoscopic Full Thickness Resection

Abstract Background and study aims Endoscopic full-thickness resection (eFTR) allows en-bloc and transmural resection of colorectal lesions for which other advanced endoscopic techniques are unsuitable. We present our experience with a novel “clip first, cut later” eFTR-device and evaluate its indications, efficacy and safety. Patients and methods From July 2015 through October 2017, 51 eFTR-procedures were performed in 48 patients. Technical success and R0-resection rates were prospectively recorded and retrospectively analyzed. Results Indications for eFTR were non-lifting adenoma (n = 19), primary resection of malignant lesion (n = 2), resection of scar tissue after incomplete endoscopic resection of low-risk T1 colorectal carcinoma (n = 26), adenoma involving a diverticulum (n = 2) and neuroendocrine tumor (n = 2). Two lesions were treated by combining endoscopic mucosal resection and eFTR. Technical success was achieved in 45 of 51 procedures (88 %). Histopathology confirmed full-thickness resection in 43 of 50 specimens (86 %) and radical resection (R0) in 40 procedures (80 %). eFTR-specimens, obtained for indeterminate previous T1 colorectal carcinoma resection, were free of residual carcinoma in 25 of 26 cases (96 %). In six patients (13 %) a total of eight adverse events occurred within 30 days after eFTR. One perforation occurred, which was corrected endoscopically. No emergency surgery was necessary. Conclusion In this study eFTR appears to be safe and effective for the resection of colorectal lesions. Technical success, R0-resection and major adverse events rate were reasonable and comparable with eFTR data reported elsewhere. Mean specimen diameter (23 mm) limits its use to relatively small lesions. A clinical algorithm for eFTR case selection is proposed. eFTR ensured local radical excision where other endoscopic techniques did not suffice and reduced the need for surgery in selected cases.

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Prospects and Challenges of Translational Corneal Bioprinting

Bioengineering ◽

10.3390/bioengineering7030071 ◽

2020 ◽

Vol 7 (3) ◽

pp. 71 ◽

Cited By ~ 2

Author(s):

Matthias Fuest ◽

Gary Hin-Fai Yam ◽

Jodhbir S. Mehta ◽

Daniela F. Duarte Campos

Keyword(s):

Tissue Engineering ◽

Ex Vivo ◽

Corneal Transplantation ◽

Human Cornea ◽

Corneal Tissue ◽

Full Thickness ◽

Future Directions ◽

Spatial Control

Corneal transplantation remains the ultimate treatment option for advanced stromal and endothelial disorders. Corneal tissue engineering has gained increasing interest in recent years, as it can bypass many complications of conventional corneal transplantation. The human cornea is an ideal organ for tissue engineering, as it is avascular and immune-privileged. Mimicking the complex mechanical properties, the surface curvature, and stromal cytoarchitecure of the in vivo corneal tissue remains a great challenge for tissue engineering approaches. For this reason, automated biofabrication strategies, such as bioprinting, may offer additional spatial control during the manufacturing process to generate full-thickness cell-laden 3D corneal constructs. In this review, we discuss recent advances in bioprinting and biomaterials used for in vitro and ex vivo corneal tissue engineering, corneal cell-biomaterial interactions after bioprinting, and future directions of corneal bioprinting aiming at engineering a full-thickness human cornea in the lab.

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