Complete endoscopic closure of gastrotomy after natural orifice translumenal endoscopic surgery using the NDO Plicator

Clinical efficacy and safety of transvaginal natural orifice transluminal endoscopic surgery for benign adnexal disease: a prospective trial

BACKGROUND

There is a scarcity of prospective clinical research evidence regarding the utilization of transvaginal natural orifice translumenal endoscopic surgery (vNOTES) as a treatment option for ovarian cysts. The objective of this study was to assess the feasibility and safety of employing vNOTES for the management of ovarian cysts.

METHODS

Our study included women between the ages of 18 and 70 who intended to undergo surgical intervention for benign lesions. Stratified blocked randomization was employed to allocate participants into groups. The main objective was to assess whether the assigned group adhered to the recommended surgical technique for ovarian cystectomy or adnexectomy, without any deviation to alternative surgical methods.

RESULTS

A total of 196 patients were included in the study, with all surgeries in each group being conducted according to the assigned procedures. Among them, the ovarian cystectomy layer included 58 cases in the vNOTES group and 58 cases in the conventional laparoscopy (CL) groups. The adnexectomy layer included 40 cases in the vNOTES group and 40 cases in the CL group. Utilizing a sensitivity analysis, the two-sided 95% lower confidence limit was determined to be 5.5% for the disparity in proportions between the vNOTES groups and CL groups. These lower limits fell below the predetermined non-inferiority margin of 10%.

CONCLUSIONS

The study findings demonstrate that vNOTES was not inferior to CL in terms of adnexectomy or ovarian cystectomy. vNOTES can be considered a more minimally invasive surgical approach, as it results in reduced postoperative pain, faster recovery, and absence of visible incisions. Overall, vNOTES proves to be a safe, feasible, and less invasive treatment option.

TRIAL REGISTRATION

This study retrospectively registered with the China Clinical Trial Registry with the registration number ChiCTR2100052223(22-10-2021).

Outcomes of Deep Mural Injury After Endoscopic Resection: An International Cohort of 3717 Large Non-Pedunculated Colorectal Polyps

BACKGROUND & AIMS

Although perforation is the most feared adverse event associated with endoscopic mucosal resection (EMR), limited data exists concerning its management. Therefore, we sought to evaluate the short- and long-term outcomes of intra-procedural deep mural injury (DMI) in an international multi-center observational cohort of large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs).

METHODS

Consecutive patients who underwent EMR for a LNPCP ≥20 mm were evaluated. Significant DMI (S-DMI) was defined as Sydney DMI Classification type III (muscularis propria injury, target sign) or type IV/V (perforation without or with contamination, respectively). The primary outcome was successful S-DMI defect closure. Secondary outcomes included technical success (removal of all visible polypoid tissue during index EMR), surgical referral and recurrence at first surveillance colonscopy (SC1).

RESULTS

Between July 2008 to May 2020, 3717 LNPCPs underwent EMR. Median lesion size was 35mm (interquartile range (IQR) 25 to 45mm). Significant DMI was identified in 101 cases (2.7%), with successful defect closure in 98 (97.0%) using a median of 4 through-the-scope clips (TTSCs; IQR 3 to 6 TTSCs). Three (3.0%) patients underwent S-DMI-related urgent surgery. Technical success was achieved in 94 (93.1%) patients, with 46 (45.5%) admitted to hospital (median duration 1 day; IQR 1 to 2 days). Comparing LNPCPs with and without S-DMI, no differences in technical success (94 (93.1%) vs 3316 (91.7%); P = .62) or SC1 recurrence (12 (20.0%) vs 363 (13.6%); P = .15) were identified.

CONCLUSIONS

Significant DMI is readily managed endoscopically and does not appear to affect technical success or recurrence.

A novel grasp-and-loop closure method for defect closure after endoscopic full-thickness resection (with video)

BACKGROUND

Endoscopic full-thickness resection (EFTR) is a minimally invasive method for en bloc resection of gastrointestinal (GI) lesions originating from the muscularis propria layer. Successful closure of the wall defect is a critical step.

OBJECTIVE

The aim of this study was to evaluate the feasibility and efficacy of a novel and simplified endoscopic grasp-and-loop (GAL) closure method using an endo-loop assisted with grasping forceps for defect closure.

METHODS

From January 2015 to March 2016, 13 patients with submucosal tumors (SMTs) originating from the muscularis propria (MP) layer underwent EFTR and were enrolled in this study. After successful tumor resection, an endo-loop was anchored onto the circumferential margin of the gastric defect with grasping forceps assistance and tightened gently. Patient characteristics, tumor size, en bloc resection, and postoperative complications were evaluated.

RESULTS

Of the 13 lesions in the stomach, two were located in the greater curvature of the mid-upper body, 11 were located in the fundus. The endoscopic GAL closure method was successfully performed after EFTR in all the 13 patients without laparoscopic assistance. The mean procedure time was 43.5 min (range 20-80 min), while the GAL closure procedure took a mean of 9.4 min (range 3-18 min). The mean resected lesion size was 1.5 cm (range 0.5-3.5 cm). Pathological diagnoses of these lesions were 11 gastrointestinal stromal tumors (GISTs) and two leiomyomas. No major adverse events occurred during or after the procedure. All the patients were discharged after a mean time of 2.4 days (range 1-4 days). No residual lesion or tumor recurrence was found during the follow-up period (median, 5 months; range, 1-15 months).

CONCLUSIONS

The endoscopic GAL closure method is feasible, effective, and safe for closing the gastric defect after EFTR in patients.

Transvaginal Laparoscopically Assisted Endoscopic Appendectomy: a major Hybrid Natural Orifice Transluminal Endoscopic Surgery case series in Asia

OBJECTIVE

Evaluation of a Hybrid Approach to NOTES and its performance relative to conventional procedures.

BACKGROUND

Globally, numerous institutions have successfully implemented minimally invasive surgeries by applying natural orifice translumenal endoscopic surgery (NOTES) techniques and achieved decreased morbidity while performing incision-less surgery. However, these techniques are still not common in surgical practice in China and Pakistan. Documenting the experiences and challenges encountered in implementing NOTES in such environments can provide guidance for NOTES implementation elsewhere.

METHODS

From May 2010 to April 2012, 16 human transvaginal appendectomies were carried out applying a hybrid NOTES technique using a solo-umbilical trocar, which provided a safe access for laparoscopic assistance during surgical procedure. After removal of the appendix transvaginally, the colpotomy was sutured under direct vision with absorbable stitches. The outcomes of cases treated with hybrid NOTES techniques were compared to those of conventional laparoscopic appendectomy.

RESULTS

All patients underwent a successful surgical procedure with no intra- or post-operative complications and provided no specific complaints during the tenth day and a monthly follow-up for 2 years. The patients convalesced promptly with healthy and satisfactory cosmetic results. Compared to conventional laparoscopic appendectomy, the hybrid NOTES operation had less post-operative pain, lower cost, and shorter hospitalization.

CONCLUSIONS

Hybrid NOTES procedures can be performed safely using a solo-umbilical trocar. Our initial experience reveals that this hybrid technique is practically feasible and associated with minimal post-operative pain, reasonable convalescence time, and improved cosmetic outcomes.

Prospective randomized comparison of gastrotomy closure associating tunnel access and over-the-scope clip (OTSC) with two other methods in an experimental ex vivo setting

BACKGROUND

Safe transgastric natural orifice transluminal endoscopic surgery (NOTES) procedures require a reliable closure of the gastrotomy. Recently a novel peritoneal access method via a submucosal tunnel has been described with encouraging preliminary results.

AIM

The aim is to compare a submucosal tunnel access plus over-the-scope clip (OTSC) system for closure with two other closure modalities.

PATIENTS AND METHODS

This is a prospective ex vivo study conducted on 42 porcine stomach models equally randomized into three groups in an academic medical center. The procedures performed in each group included: (1) Tunnel (6 cm) + endoclips; (2) Knife + balloon dilation access + OTSC; and (3) Tunnel + OTSC. A pressurized air-leak test was performed to evaluate the strength of the closure. Stomach volumes, procedure times, number of clips, and incision sizes were also registered.

RESULTS

The mean air-leak pressure was statistically higher in Group 3 than in Groups 1 and 2-95.2 ± 19.3 mmHg versus 72.5 ± 35.2 and 79.0 ± 24.5 mmHg (P < 0.05). The gastrotomy creation times for Groups 1, 2, and 3 were 28.0 ± 10.1, 4.3 ± 1.4, and 20.1 ± 10.6 minutes, respectively, with significantly lower time in Group 2 (P < 0.001). The closure times were 16.1 ± 6.1, 6.5 ± 1.2, and 5.3 ± 3.0 minutes, respectively, and significantly longer in the endoclip group (P < 0.001). There were no differences in the volumes and the incision sizes among the three groups.

CONCLUSION

The combination of a submucosal tunnel access and OTSC offers a stronger closure than the other methods studied.

Endoscopic ultrasound-assisted direct peritoneal visualization with a small-caliber scope: A proof of concept study in a swine model

BACKGROUND

Laparoscopic and natural orifice transluminal endoscopic surgery techniques can diagnose peritoneal findings that suggest tumor cell dissemination. However, they have not been incorporated into routine practice, mainly owing to their complexity. To develop a minimally invasive endoscopic technique for the diagnosis of peritoneal findings, we conducted feasibility study using an acute swine model.

MATERIALS AND METHODS

This study involved six domestic pigs. Trans-gastric access to the peritoneal cavity was performed utilizing an endoscopic ultrasound fine needle aspiration (EUS-FNA) technique. After dilation of the needle hole with a biliary dilatation catheter and balloon, a small-caliber scope was inserted into the peritoneal cavity. Peritoneal images were obtained with the scope and a high-resolution microendoscope (HRME). Main outcome measurements were technical feasibility and time needed to access the peritoneal cavity.

RESULTS

Direct visualization of the peritoneum was successful in all six pigs and gained access to the gross appearance of the peritoneal cavity. HRME imaging with topical contrast agent also obtained reasonable quality images representing nuclei of the peritoneal mesothelium. Average operation time from the initiation of EUS-FNA to acquiring peritoneal images was 26.5 min (range 15-40 min). Autopsy found no damage to the adjacent organs, and stomach wall defects were tightly closed with hemostasis clips.

CONCLUSION

EUS-assisted direct peritoneal visualization with small-caliber scope is technically feasible. HRME may assist in the diagnosis of findings on the peritoneum.

Natural-orifice translumenal endoscopic surgery (NOTES): minimally invasive evolution or revolution?

Since the first animal experimental laparoscopy in 1902, minimal access techniques have revolutionized surgery. Using the natural orifice dates back to at least the second century when Soranus performed a vaginal hysterectomy. The main difference between traditional endolumenal surgery and the translumenal approach of natural-orifice translumenal endoscopic surgery (NOTES) is the intentional puncture of a healthy organ in NOTES to access a cavity or other organ. The aim of this review was to examine the past, present, and potential future role of NOTES in the context of other developments in minimal access surgery. NOTES is at an early stage in its development and a convincing benefit over laparoscopy has not been demonstrated. Concerns regarding complications, for example of viscerotomy closure, have limited the widespread uptake of pure NOTES. However, it is likely that technological advances for NOTES surgery will enhance conventional laparoscopic and endoscopic techniques.

Endoscopic closure of experimental iatrogenic gastric fundus perforation using over-the-scope clips in a surviving canine model

BACKGROUND AND AIM

To evaluate the effectiveness and outcomes of endoscopic closure of a gastric fundus perforation using over-the-scope clips (OTSCs) system in a surviving canine model.

METHODS

Gastric fundus perforations (20-mm diameter) were created by an endoscopic needle-knife in six dogs. The perforations then were closed by the OTSC system. Gastroscopy was performed to evaluate the postoperative perforation healing every week. The animals were sacrificed 4 weeks later to examine the possible intraperitoneal complications, and the healing of the perforation was examined histopathologically.

RESULTS

The gastric fundus perforations could primarily be closed using one OTSC in each experimental dog, and the mean time of the procedure was 17.3 ± 7.6 min (9-26 min). All animals survived without postoperative complications. The OTSC retention was observed in one dog at the end of 4 weeks, and the apparent foreign-body reaction was examined pathologically.

CONCLUSIONS

Our surviving animal study demonstrated that the OTSC clip system could reliably close gastric fundus perforations without complications.

Feasibility study of secure closure of gastric fundus perforation using over-the-scope clips in a dog model

BACKGROUND AND AIM

Gastric fundus perforation is a serious complication of endoscopic mucosal resection and endoscopic submucosal dissection performed for the removal of early gastric cancers or subepithelial tumors. The novel over-the-scope clip (OTSC) has recently been found to be effective for closing gastrointestinal-tract perforations and accesses for natural orifice transluminal endoscopic surgery. However, feasibility studies of OTSCs in gastric fundus perforation are still lacking. The aim of this study was therefore to demonstrate the feasibility of endoscopic closure of gastric fundus perforation using the OTSC system in a dog model.

METHODS

Gastric fundus perforations were created by needle-knife electrocautery in seven dogs. The perforations were then closed using the OTSC clipping system. Stomach distension was maintained by maximum insufflation with air and methylene blue solution (500 mL) was instilled to submerge the closed perforation. Leaks were detected laparoscopically.

RESULTS

Perforations were closed in all seven cases with a mean time of 18.5 ± 6.4 min (11-28 min). Twin Grasper assistance failed to release the OTSCs in two of the seven cases (2/7, 28.6%) because of difficulties associated with the J-maneuver (retroflexion of endoscope) required for the gastric fundus procedure, and OTCS were forced into place by suction. Minor leakage was observed in one case (1/7, 14.3%). No damages related to the clip system were found during postmortem examinations.

CONCLUSIONS

Despite difficulties associated with the J-maneuver of the endoscope, this small series demonstrated that sufficient closure of gastric fundus perforation could be achieved using the OTSC system.

New laser soldering-based closures: a promising method in natural orifice transluminal endoscopic surgery

BACKGROUND

Complete closure of gastrotomy is the linchpin of safe natural orifice transgastric endoscopic surgery.

OBJECTIVE

To evaluate feasibility and efficacy of a new method of gastrotomy closure by using a sutureless laser tissue-soldering (LTS) technique in an ex vivo porcine stomach.

DESIGN

In vitro experiment.

SETTING

Experimental laboratory.

INTERVENTIONS

Histological analysis and internal and external liquid pressure with and without hydrochloric acid exposure were determined comparing gastrotomy closure with LTS and with hand-sewn surgical sutures.

MAIN OUTCOME MEASUREMENTS

Comparison of LTS and hand-sewn surgical gastrotomy closure. The primary outcome parameter was the internal leak pressure. Secondary parameters were the difference between internal and external leak pressures, the impact of an acid environment on the device, histological changes, and feasibility of endoscopic placement.

RESULTS

The internal liquid leak pressure after LTS was almost twice as high as after hand-sewn surgical closure (416 ± 53 mm Hg vs 229 ± 99 mm Hg; P = .01). The internal leak pressure (416 ± 53 mm Hg) after LTS was higher than the external leak pressure (154 ± 46 mm Hg; P < .0001). An acidic environment did not affect leak pressure after LTS. Endoscopic LTS closure was feasible in all experiments. Histopathology revealed only slight alterations beneath the soldering plug.

LIMITATIONS

In vitro experiments.

CONCLUSIONS

Leak pressure after LTS closure of gastrotomy is higher than after hand-sewn surgical closure. LTS is a promising technique for closure of gastrotomies and iatrogenic perforations. Further experiments, in particular survival studies, are mandatory.

Current progress on natural orifice transluminal endoscopic surgery (NOTES)

Natural orifice transluminal endoscopic surgery (NOTES) has received considerable interest in recent years as a novel surgical technique. Here, we aim to review the current progress on NOTES, particularly focusing on the advantages and complications related to NOTES, the recent advances of surgical approaches, new instruments for closure of the natural orifice incision, and the newly developed platform for NOTES. Finally, we make a prediction of the conceivable applications of NOTES on human subjects.

Natural orifice transesophageal endoscopic surgery: state of the art

The main goal of Natural Orifice Transluminal Endoscopic Surgery (NOTES) is performing surgery avoiding skin incisions. Theoretical advantages of NOTES include decreased postoperative pain, reduction/elimination of general anesthesia, improved cosmetic outcomes, elimination of skin incision-related complications such as wound infections and hernias, and increased overall patient satisfaction. Although various forms of port creation to accomplish thoracic NOTES procedures have been proposed, transesophageal NOTES has been shown to be the most reliable one. The evolution of endoscopic submucosal transesophageal access resulted in the development of per-oral endoscopic myotomy (POEM), which had a fast transition to clinical practice. The authors present a review of the current state of the art concerning transesophageal NOTES, looking at its potential for diagnostic and therapeutic interventions as well as the hurdles yet to be overcome.

Natural Orifice Surgery (NOS)-the next step in the evolution of minimally invasive surgery

Endoscopy, which was introduced in the 20(th) century, changed the outcome of surgery by reducing the need for analgesia and shortening hospital stay. Any new surgical method should improve safety and outcome. At the beginning of the 21(st) century, the use of natural orifice surgery is a promising progress. The transgastric and transdouglas approaches are currently being investigated and evaluated. The transgastric approach still has a long way to go due to objective problems such as infections, stomach acidity, and the optimal way to ensure the safe closure of gastrotomy. The transdouglas approach, however, is already starting to establish itself and it seems that with the construction of designated instruments it will prevail in the 21(st) century.

Future directions in bariatric surgery

Bariatric surgery is a field in rapid evolution, and the speed of this evolution has been accelerating over the last several decades. A thorough understanding of past developments is crucial to anticipating the future intelligently. The trends that have driven evolution historically often persist, and continue to be influential in the future. With this in mind, this article briefly outlines the historical and current trends in bariatric surgery, and follows the trajectory of these trends into the future to anticipate the technologies and techniques that will be most important to the field in the coming years.

Natural orifice transluminal endoscopic surgery: New minimally invasive surgery come of age

Although in the past two decades, laparoscopic surgery, considered as a great revolution in the minimally invasive surgery field, has undergone major development worldwide, another dramatic surgical revolution has quietly appeared in recent years. Ever since Kalloo’s first report on transgastric peritoneoscopy in a porcine model in 2004, interest in a new surgical procedure named natural orifice transluminal endoscopic surgery (NOTES) has blossomed worldwide. Considering that a NOTES procedure could theoretically avoid any abdominal incision, operation-related pain and scarring, many surgeons and endoscopists have been enthusiastic in their study of this new technique. In recent years, several NOTES studies have been carried out on porcine models and even on humans, including transvaginal cholecystectomy, transgastric appendectomy, transvaginal appendectomy, and transvesical peritoneoscopy. So what is the current situation of NOTES and how many challenges do we still face? This review discusses the current research progress in NOTES.

Gastrotomy closure with a new tissue anchoring device: A porcine survival study

AIM: To evaluate the feasibility, reproducibility and efficacy of a new tissue anchoring device in a porcine survival model.

METHODS: Gastrotomies were performed using a needle-knife and balloon dilator in 10 female Yorkshire pigs weighing 30-35 kg. Gastric closure was attempted using a new tissue anchoring device. The tightness of the closure was confirmed by means of air insufflation and the ability to maintain gastric distension with stability in peritoneal pressure measured with a Veress needle. All animals were monitored daily for signs of peritonitis and sepsis over 14 d. During necropsy, the peritoneal cavity and the gastric access site were examined.

RESULTS: Transgastric access, closure and 14 d survival was achieved in all pigs. The mean closure time was 18.1 ± 19.2 min and a mean of 2.1 ± 1 devices were used. Supplementary clips were necessary in 2 cases. The closure time was progressively reduced (24.8 ± 13.9 min in the first 5 pigs vs 11.4 ± 5.9 min in the last 5, P = NS). At necropsy, the gastric access site was correctly closed in all cases with all brace-bars present. One device was misplaced in the mesocolon. Minimal adhesions were observed in 3 pigs and signs of mild peritonitis and adhesions in one.

CONCLUSIONS: The use of this new tissue anchoring device in porcine stomachs is feasible, reproducible and effective and requires a short learning curve.

Closure of gastrotomy in natural orifice transluminal endoscopic surgery: a feasibility study using an ex vivo model comparing endoloop with endoclip

BACKGROUND

Closure of access site is one of the key issues that will determine the development of natural orifice transluminal endoscopic surgery. Our study was designed to compare the effectiveness of gastrotomy closure using endoloop and endoclip with hand-sewn closure as a control.

METHODS

Gastrotomy was carried out on 24 ex vivo porcine stomachs and the gastrotomies were randomized to be closed with either hand-sewn, endoloop or endoclip techniques. A 2 cm gastrotomy was created with a needle knife and sphincterotome and the defects closed thereafter. We measured the time to closure of gastrotomy and the pressure at which the closure leaked.

RESULTS

Three endoloops were required for all the closures in the endoloop group. In the endoclip group, the mean (range) number of endoclips used was 10 (8-13). There was no difference in the median closure times between endoloop 28 (16-58) min and endoclip 30 (21-40) min; however, time for hand-sewn closure was much shorter (3-5 min). All stomachs were successfully distended with air without leak at the end of the procedure and none experienced fluid leak. The endoclip closure endured a significantly higher median (range) pressure of 72.5 mmHg (15-80 mmHg) before leaking compared to that of an endoloop 25 mmHg (15-37 mmHg) (P < 0.001). The hand-sewn gastrotomy leaked at pressure of 95 mmHg (75-130 mmHg). The majority of air leaks were from the wound site. In the endoclip group, two leaks were noted at the clip bite site.

CONCLUSION

  In a bench-top model, endoclips seem to be better for gastrotomy closure because of their potential to endure relatively higher pressure without any prolongation of application time. Animal survival studies are needed to explore technical and wound-closure-related problems arising as a result of use of endoclips and endoloops for gastrotomy closure.

Endoscopic closure of GI fistulae by using an over-the-scope clip (with videos)

BACKGROUND

Preclinical studies have demonstrated the over-the-scope clip (OTSC) to be feasible and safe for closure of gastric, duodenal, and colonic perforations. A retrospective clinical study demonstrated the feasibility and preliminary safety of the OTSC for the treatment of GI bleeding and closure of acute GI perforations.

OBJECTIVE

Because the OTSC allows rapid and easy endoscopic organ wall closure, we hypothesized that it might be a useful tool to close GI fistulae.

DESIGN

Case series.

SETTING

Academic medical center.

PATIENTS

Four consecutive patients with GI fistulae.

INTERVENTIONS

In all patients, a 12-mm OTSC, in combination with the dedicated twin grasper, anchor device, or endoscopic suction, was used to facilitate endoscopic closure.

MAIN OUTCOME MEASUREMENTS

In 2 cases, OTSCs allowed complete closure of a posttraumatic esophagopulmonary fistula and a chronic gastrocutaneous fistula. Leak tests and follow-up examination demonstrated complete leakproof closures. In 1 esophagopulmonary fistula and 1 jejunocutaneous fistula, the initial closure attempts using OTSCs were not successful because of chronic fibrotic changes and scarring at the fistula site. Both OTSCs were removed by using an endoscopic grasping forceps. The mean procedure time was 54 minutes (range 24-93 minutes). There were no procedure-related complications.

LIMITATIONS

Small sample size.

CONCLUSIONS

The OTSC seems to be a feasible device to close chronic fistulae of the GI tract. It can achieve leakproof, full-thickness closure of transmural defects. Nevertheless, in circumstances of severe fibrosis and scarring, complete incorporation of the defect into the applicator cap and successful OTSC application might not be possible.

Transvaginal laparoscopically assisted endoscopic cholecystectomy: preliminary clinical results for a series of 43 cases in China

BACKGROUND

Transvaginal cholecystectomy has been performed successfully at several research institutions worldwide using natural orifice transluminal endoscopic surgery (NOTES) techniques. However, it is a growing new surgical concept in China. Several technical challenges hinder the safe clinical application of NOTES. This study investigated transvaginal endoscopic cholecystectomy performed with the assistance of a single umbilical trocar and achieved helpful initial clinical experience.

METHODS

From May 2009 to April 2010, a total of 43 transvaginal human cholecystectomies were performed. A single umbilical trocar was used for safe access and laparoscopic assistance during the operation. After the gallbladder had been removed through the vagina, the colpotomy was closed with absorbable stitches under direct vision. In addition, Student's t-test was performed for two samples to estimate the superiority of NOTES over a conventional laparoscopic cholecystectomy (LC) operation.

RESULTS

The procedure was successfully completed for all the patients. No intra- or post-operative complications occurred. The patients recovered promptly after surgery, and all were satisfied with ideal cosmetic outcomes. The postoperative pain, hospital stay, and cost of hospitalization with NOTES were much less than with conventional LC operations.

CONCLUSIONS

Although endoscopic instruments specifically designed for NOTES are not available, the addition of an umbilical trocar is an optimal way to allow safe performance of NOTES procedures in an easily reproducible manner. The authors' initial experience demonstrates that this hybrid technique is potentially feasible and effective for reducing postoperative pain and recovery times while improving the cosmetic results of transvaginal cholecystectomy.

What are the elements of safe gastrotomy closure in NOTES? A systematic review

INTRODUCTION

The safe closure of the gastrotomy needs to be established before natural orifice translumenal endoscopic surgery (NOTES) can be extended to routine clinical practice. As yet no optimum closure method has been identified.

METHODS

A systematic review of the literature on gastrotomy closure modalities for NOTES up until December 2009 was undertaken. An assessment of each closure modality was determined using specified quantitative and qualitative parameters.

RESULTS

There were 46 studies included in this review describing 20 closure techniques. Some robustly designed experimental studies have now been published particularly in relation to the over-the-scope clip system.

CONCLUSION

Current evidence is experimental and therefore limited, but there appears to be some clarification in the direction of the innovative process in this area outlining favorable characteristics of an ideal system. Based on the studies examined in this review, a standardized assessment method is summarized for future in vivo studies, necessary prior to phase 1 trials.

Hybrid NOTES transgastric cholecystectomy with reliable gastric closure: an animal survival study

Background

Secure transluminal closure remains the most fundamental barrier to safe translation of transgastric natural orifice transluminal endoscopic surgery (NOTES) procedures to humans. Obtaining optimal critical view of safety (CVS) is a prerequisite to performing cholecystectomy avoiding common bile duct injury.

Objectives

(1) To evaluate feasibility and safety of hybrid transgastric NOTES cholecystectomy. (2) To evaluate feasibility and reliability of gastrotomy closure using a novel Over-The-Scope-Clip (OTSC; Ovesco) in survival porcine experiments.

Methods

Laparoscopic access to the abdominal cavity was obtained by two 2-mm and one umbilical optical trocar(s). Gastric access was created by balloon dilatation of a needle knife puncture up to 18 mm. Exposure of CVS was obtained and evaluated by aid of a 2-mm device. Subsequently the cystic duct and artery were clipped endoscopically. After laparoscopic dissection the specimen was extracted via the stomach. The gastrotomy was closed endoscopically using the OTSC. Necropsy was performed after 10 days with inspection of gastrotomy and peritoneal cavity for complications. Experiments were planned in 3 acute and 16 survival pigs. Main outcome parameters were documented exposure of CVS, successful cholecystectomy and closure, uncomplicated survival and histology-confirmed full-thickness closure.

Results

In all 16 survival experiments CVS was obtained satisfactorily and hybrid cholecystectomy was successfully performed [100%; 95% confidence interval (CI): 81–100%]. Transgastric closure was endoscopically successful in all experiments in mean time of 7 min [standard deviation (SD) 3 min]. At necropsy 10 days after surgery there were no signs of (infectious) complications. Histology confirmed full-thickness healing with 100% success (95% CI: 81–100%).

Conclusion

Hybrid transgastric NOTES cholecystectomy is feasible, safe and results in optimal CVS. Use of OTSC for gastrotomy closure is feasible, reliable and results in histology-proven full-thickness closure in survival porcine experiments.

Electronic supplementary material

The online version of this article (doi:10.1007/s00464-010-1242-4) contains supplementary material, which is available to authorized users.

Loop-Anchor Purse-String Closure of Gastrotomy in NOTES® Procedures: Survival Studies in a Porcine Model

Introduction: Transgastric NOTES® procedures remain without a simple method to close the gastrotomy. In four survival swine studies, we have tested a novel gastric closure device: the loop-anchor purse-string (LAPS) closure system. Methods: In four anesthetized pigs, an endoscopic gastrotomy was performed. Four loop anchors were arrayed in a 2-cm square pattern around the gastrotomy. The endoscope was passed into the abdominal cavity, and the gastrotomy was cinched closed. Results: Procedure times ranged from 50-180 minutes. Three pigs survived 14 days. One animal was sacrificed early due to signs of sepsis. Another animal developed fevers and was treated with antibiotics. At necropsy, there were no abscesses, including in the septic animal. Histologic examination revealed evidence of healing in all animals. Discussion: The LAPS system holds promise with early success in an animal model. Future human studies are needed to determine viability as a human visceral closure device.

Gastric wall healing after NOTES procedures: closure with endoscopic clips provides superior histological outcome compared with threaded tags closure

BACKGROUND

Closure of the transgastric access to the peritoneal cavity is a critical step in natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

To perform a direct comparison of the histological healing post clips and threaded tags (T-tags) closure after transgastric NOTES procedures.

DESIGN AND INTERVENTION

Twelve survival porcine experiments. After standardized endoscopic gastric wall puncture, balloon-dilation, and transgastric peritoneoscopy, closure of the gastric wall was performed with either clips or T-tags. Necropsy at 14 days was performed for histological evaluation of 2-mm interval transversal cross sections of the gastrotomy site.

MAIN OUTCOME MEASUREMENTS

Histological healing of the gastric wall opening.

RESULTS

Endoscopic closure of the gastrotomy was successfully achieved in all 12 animals, followed by an uneventful 2-week clinical follow-up. Transmural healing was seen in 3 (75%) animals after clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .06). Gastric wall muscular bridging was observed in 4 (100%) animals with clip closure compared with only 1 (12.5%) in the group with T-tag closure (P = .01).

LIMITATIONS

Animal model with short-term follow-up.

CONCLUSIONS

Endoscopic clip closure results in a layer-to-layer transmural healing of the gastric wall. In contrast, T-tag gastric wall plication impairs gastric layer bridging. These findings might guide the future design of new endoscopic devices and techniques for gastrotomy closure after NOTES procedures.

Do gastrotomies require repair after endoscopic transgastric peritoneoscopy? A controlled study

BACKGROUND

The optimal method for closing gastrotomies after transgastric instrumentation has yet to be determined.

OBJECTIVE

To compare gastrotomy closure with endoscopically delivered bioabsorbable plugs with no closure.

DESIGN

Prospective, controlled study.

SETTING

Animal laboratory.

SUBJECTS

Twenty-three dogs undergoing endoscopic transgastric peritoneoscopy between July and August 2007.

INTERVENTIONS

Endoscopic anterior wall gastrotomies were performed with balloon dilation to allow passage of the endoscope into the peritoneal cavity. The plug group (n = 12) underwent endoscopic placement of a 4 x 6-cm bioabsorbable mesh plug in the perforation, whereas the no-treatment group (n = 11) did not. Animals underwent necropsy 2 weeks after the procedure.

MAIN OUTCOME MEASUREMENTS

Complications related to gastrotomy closure, gastric burst pressures, relationship of burst perforation to gastrotomy, and the degree of adhesions and inflammation at the gastrotomy site.

RESULTS

After the gastrotomy, all dogs survived without any complications. At necropsy, burst pressures were 77 +/- 11 mm Hg and 76 +/- 15 mm Hg (P = .9) in the plug group and no-treatment group, respectively. Perforations occurred at the site of the gastrotomy in 2 of 12 animals in the plug group and in none of the 11 dogs in the no-treatment group (P = .5). Finally, there were minimal adhesions in all dogs (11/11) in the no-treatment group and minimal adhesions in 3 and moderate adhesions or inflammatory masses in 9 of the 12 animals in the plug group (P = .004).

LIMITATIONS

Small number of subjects, animal model, no randomization. Gastrotomy trauma during short peritoneoscopy may not be applicable to longer procedures.

CONCLUSIONS

After endoscopic gastrotomy, animals that were left untreated did not show any clinical ill effects and demonstrated adequate healing, with fewer adhesions and less inflammation compared with those treated with a bioabsorbable plug.

Peritoneal inflammatory response of natural orifice translumenal endoscopic surgery (NOTES) versus laparoscopy with carbon dioxide and air pneumoperitoneum

BACKGROUND

The immunologic and physiologic effects of natural orifice translumenal endoscopic surgery (NOTES) versus traditional surgical approaches are poorly understood. Previous investigations have shown that NOTES and laparoscopy share similar inflammatory cytokine profiles except for a possible late-phase tissue necrosis factor-alpha (TNF-alpha) depression with NOTES. The local peritoneal reaction and immunomodulatory influence of pneumoperitoneum agents in NOTES also are not known and may play an important role in altering the physiologic insult induced by NOTES.

METHODS

In this study, 51 animals were divided into four study groups, which respectively underwent abdominal exploration via transgastric NOTES using room air (AIR) or carbon dioxide (CO(2)) or via laparoscopy (LX) using AIR or CO(2) for pneumoperitoneum. Laparotomy and sham surgeries were additionally performed as control conditions. Measurements of TNF-alpha, interleukin-1beta (IL-1beta), and IL-6 were performed for peritoneal fluid collected after 0, 2, 4, and 6 h and on postoperative days (PODs) 1, 2, and 7.

RESULTS

Of the 45 animals assessed, 6 were excluded because of technical operative complications. The findings showed that LX-CO(2) generated the most pronounced response with all three inflammatory markers. However, no significant differences were detected between LX-CO(2) and either NOTES group at these peak points. No differences were encountered between NOTES-CO(2) and NOTES-AIR. Subgroup comparisons showed significantly higher levels of TNF-alpha and IL-6 with NOTES-CO(2) than with LX-AIR on POD 1 (p = 0.022) and POD 2 (p = 0.002). The LX-CO(2) subgroup had significantly higher levels of TNF-alpha than the LX-AIR subgroup at 4 h (p = 0.013) and on POD 1 (p = 0.021). No late-phase TNF-alpha depression occurred in the NOTES animals.

CONCLUSION

The local inflammatory reaction to NOTES was similar to that with traditional laparoscopy, and the previously described late-phase systemic TNF-alpha depression in serum was not reproduced. At the peritoneal level, NOTES is no more physiologically stressful than laparoscopy. Furthermore, regardless of which gas was used, the role of the pneumoperitoneum agent did not affect the cytokine profile after NOTES, suggesting that air pneumoperitoneum is adequate for NOTES.

Directed submucosal tunneling permits in-line endoscope positioning for transgastric natural orifice translumenal endoscopic surgery (NOTES)

BACKGROUND

Submucosal dissection is demonstrated to be a technically feasible, safe means of obtaining peroral transgastric peritoneal access for natural orifice translumenal endoscopic surgery (NOTES). The authors hypothesized that their previously described self-approximating translumenal access technique (STAT) could be used to create directed gastric submucosal tunnels permitting in-line endoscope positioning with predetermined abdominal locations that might otherwise be difficult to access.

METHODS

In this study, 14 domestic farm swine underwent peroral transgastric peritoneoscopy. Under direct endoscopic visualization, a submucosal tunnel was created by dissecting between the mucosal and muscular layers of the stomach. Each tunnel was created with one of four intraabdominal locations (right upper quadrant, left upper quadrant, lesser sac, and pelvis) as the final target for in-line endoscope positioning. Once peritoneal access had been achieved, in-line positioning was assessed and peritoneoscopy was performed. The submucosal tunnels were closed with endoscopically placed clips. The animals were killed 2 weeks after the procedure, and necropsy was performed.

RESULTS

Submucosal tunnels were successfully directed at predetermined intraabdominal targets in 12 of the 14 animals. The mean dissection time required to create the tunnel was 51 +/- 32 min. All the transgastric tunnels were successfully closed with endoscopically placed clips (mean, 3.2 +/- 1.1), and at necropsy showed no evidence of gastrotomy leak in any of the animals. One animal experienced a duodenal perforation unrelated to the transgastric tunneling and was killed on postoperative day 2. The remaining animals recovered and gained weight (mean, 5.5 +/- 1.2 kg) in the 2-week survival period.

CONCLUSIONS

Directed submucosal dissection is technically feasible in a porcine model and permits in-line endoscope positioning with predetermined abdominal target locations. The STAT approach provides safe peritoneal access, allows for a simple reliable endoclip closure, and has an excellent short-term survival rate. This method of achieving transgastric access may be an enabling technique for future NOTES procedures.

In vivo assessment of gastrotomy closure with over-the-scope clips in an experimental model for varicocelectomy (with video)

BACKGROUND

Gastrotomy closure remains the major limiting factor for human translation of transgastric surgery; the over-the-scope clip (OTSC) system was proposed as a possibility for this purpose. Transgastric access is good for a pelvic approach, making varicocelectomy a possible indication for natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

To evaluate the reliability of the OTSC system in vivo after transgastric testicular vessel ligation (varicocelectomy model).

DESIGN

There were 3 experimental groups (5 animals in each): groups 1 and 3, gastrotomy dilation up to 18 mm, surgery was performed with a double-channel endoscope; group 2, gastrotomy dilation up to 13 mm, surgery was performed with a single-channel endoscope.

SETTING

Surgical Sciences Research Domain, Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal.

INTERVENTIONS

Bilateral testicular vessel ligation by transgastric access. Gastrotomy closed with the largest version of OTSC system (12 mm): a single clip in groups 1 and 2, and 2 clips in group 3. Animals were monitored for 2 weeks, killed, and submitted for necropsy.

MAIN OUTCOME MEASUREMENTS

Adequacy of closure and healing after the use of the OTSC system. Statistical analysis.

RESULTS

Vessel ligation was easily achieved in all groups. Although differences in the complication rate did not reach statistical significance (P = .099), there was a clear tendency for a better prognosis in groups 2 and 3 than group 1. In fact, only 2 animals from group 1 had complications related to incomplete gastrotomy closure.

LIMITATIONS

Small number of animals per group; nonrandomized study.

CONCLUSIONS

The OTSC system was shown to be easy and efficient for gastrotomy closure in a survival experimental model of varicocelectomy, when correctly matching the gastrotomy size with the clip size and/or number.

Loop-anchor purse-string versus endoscopic clips for gastric closure: a natural orifice transluminal endoscopic surgery comparison study using burst pressures

BACKGROUND

The success of natural orifice surgery depends on a reliable, secure closure of the opening in the gut. Few tests of the integrity of these closures have been published.

OBJECTIVE

To determine whether a gastrotomy can be closed safely and effectively from within the stomach by using looped T-anchors-a novel, endoscopically placed device.

DESIGN

Head-to-head comparison trial of 2 closure methods in 9 explanted porcine stomachs.

SETTING

Animal laboratory.

INTERVENTION

Paired gastrotomies were made in porcine explants. One was closed by using endoscopic clips, and the other was closed by using modified T-anchors in a purse-string fashion.

MAIN OUTCOME MEASUREMENTS

Gastric transmural pressure gradients at bursting of these closures were measured while the explanted stomachs were inflated with a high-pressure insufflator.

RESULTS

The mean burst pressure of the looped T-anchors was 27.3 mm Hg, whereas that of the clip closures was 14 mm Hg. By using 10 mm Hg as a threshold for a "secure" closure, 7 of 9 clip closures failed to meet the threshold value, whereas all 9 of the T-anchor closures met or exceeded the threshold value (P = .0023, 2-tailed Fisher exact test).

LIMITATION

Nonsurvival study.

CONCLUSION

Looped T-anchors provide a secure gastric closure for natural orifice surgery and are superior to endoscopic clips for this purpose.

NOTES: new dimension of minimally invasive surgery

Natural orifice transluminal endoscopic surgery (NOTES) is an emerging experimental alternative to conventional surgery. NOTES eliminates abdominal incisions and incision-related complications by combining endoscopic and laparoscopic techniques to diagnose and treat abdominal pathology. Since the first NOTES was reported by Kalloo et al. in 2004, significant achievements in the laboratory have occurred. Clinical use in humans has been limited, but several cases and one small clinical trial were published recently. As a further technical revolution in minimally invasive surgery, NOTES has the promising potential to be safer, less invasive, provide better cosmesis and possibly be more cost-effective. The purpose of the present article was to review the development and current status of NOTES and highlight important advances associated with this innovative approach.

Natural orifice transluminal endoscopic surgery gastrotomy closure with an over-the-endoscope clip: a randomized, controlled porcine study (with videos)

BACKGROUND

Secure endoscopic closure of transgastric natural orifice transluminal endoscopic surgery (NOTES) access is of paramount importance. The over-the-scope clip (OTSC) system has previously been shown to be effective for NOTES gastrotomy closure.

OBJECTIVE

To compare OTSC gastrotomy closure with surgical closure.

DESIGN

Randomized, controlled animal study.

SETTING

Animal facility laboratory.

ANIMALS

Thirty-six female domestic pigs.

INTERVENTIONS

Gastrotomies were created by using a needle-knife and an 18-mm balloon. The animals were subsequently randomized to either open surgical repair with interrupted sutures or endoscopic repair with 12-mm OTSCs. In addition, pressurized leak tests were performed in ex vivo specimens of 18-mm scalpel incisions closed with suture (n = 14) and of intact stomachs (n = 10).

MAIN OUTCOME MEASUREMENTS

The mean time for endoscopic closure was 9.8 minutes (range 3-22, SD 5.5). No complications occurred during either type of gastrotomy closure. At necropsy, examination of all OTSC and surgical closures demonstrated complete sealing of gastrotomy sites without evidence of injury to adjacent organs. Pressurized leak tests showed a mean burst pressure of 83 mm Hg (range 30-140, SD 27) for OTSC closures and 67 mm Hg (range 30-130, SD 27.7) for surgical sutures. Ex vivo hand-sewn sutures of 18-mm gastrotomies (n = 14) exhibited a mean burst pressure of 65 mm Hg (range 20-140, SD 31) and intact ex vivo stomachs (n = 10) had a mean burst pressure of 126 mm Hg (range 90-170, SD 28). The burst pressure of ex vivo intact stomachs was significantly higher compared with OTSC closures (P < .01), in vivo surgical closures (P < .01), and ex vivo hand-sewn closures (P < .01). There was a trend toward higher burst pressures in the OTSC closures compared with surgical closures (P = .063) and ex vivo hand-sewn closures (P = .094). In vivo surgical closures demonstrated similar burst pressures compared with ex vivo hand-sewn closures (P = .848).

LIMITATIONS

Nonsurvival setting.

CONCLUSION

Endoscopic closure by using the OTSC system is comparable to surgical closure in a nonsurvival porcine model. This technique is easy to perform and is suitable for NOTES gastrotomy closure.

Transgastric and Transperineal Natural Orifice Translumenal Endoscopic Surgery (NOTES) in an Appendectomy Test Bed

Introduction. Our purpose was to establish a NOTES appendectomy test bed to evaluate whether the transgastric or transperineal (transvaginal) approach is most efficient. Methods. Using the uterine horns of female pigs as a model for appendectomy, 18 NOTES appendectomies were performed in 2 arms: 9 transgastric and 9 transvaginal. The primary outcome was mean total operative time for each technique excluding access closure. Secondary outcomes were peritoneal access and resection times. Means were compared using Student’s t-test. Results. Transgastric cases were faster than transperineal (46.5 ± 14.5 vs 60.0 ± 20.2 minutes, P = .02). Most of the improvement in transgastric times was due to faster resection (37.9 ± 17.4 vs 51.3 ± 16.5 minutes, P = .03). Neither approach was faster for peritoneal access (8.2 ± 3.4 vs 8.3 ± 4.5 minutes, nonsignificant). A significant learning curve was not demonstrated for the transgastric approach (53.0 vs 40.3 minutes, nonsignificant). A significant learning curve was demonstrated for the transperineal approach (76.0 vs 46.7 minutes, P = .02). Transperineal times improved over the study and approached transgastric; however, the last three transgastric cases were still significantly faster than the last three transperineal (40.3 vs 46.7 minutes, P = .02). No complications occurred in either group. Conclusions. The transgastric as compared with transperineal approach to NOTES appendectomy resulted in improved operative time in this model. The transperineal approach demonstrated a significant learning curve with operative times between techniques converging over time. This NOTES appendectomy test bed is suitable for evaluating NOTES innovations.

Preliminary performance of a flexible cap and catheter-based endoscopic suturing system

BACKGROUND

Translation of natural orifice transluminal endoscopic surgery (NOTES) into clinical applications requires efficient and reliable enterotomy closure.

OBJECTIVE

To evaluate a prototype endoscopic suturing system for enterotomy closure.

DESIGN

This study took place in an ex vivo animal laboratory. Isolated porcine stomachs were contained within a plastic molded abdominal torso. The device specifications included a curved needle, end-cap assembly with a side-mounting wire-actuation channel, a needle-exchange assembly that operates within an endoscopic working channel, and a detachable needle tip attached to suture material.

INTERVENTIONS

Mucosal templates (3-cm circular markings) for targeted suture placement were created along the anterior wall of the stomach (cardia, antrum, and body). Device performance and functionality were studied in 3 ways: suture placement, purse-string closure, and edge-to-edge gastrotomy closure. Interrupted and running stitches were placed with the endoscope straight and retroflexed. Simple leak testing was conducted.

RESULTS

Sutures could accurately be placed at preset templated markings. Creation of a purse-string gastrotomy closure confirmed the capability to place a set of circumferential full-thickness running sutures during a single endoscopic intubation that resulted in a leak-proof closure. Edge-to-edge full-thickness tissue apposition was accomplished, which provided a water-tight closure of an 18-mm gastrotomy. The device worked consistently, without any problems.

CONCLUSIONS

This endoscopic suturing device provided accurate placement of full-thickness sutures during a single intubation and permitted satisfactory tissue apposition. Standardized leak testing is needed for further development and evaluation of new devices. The catheter-driven needle actuator and the transfer-component system were intuitive and universally adaptable to any endoscope. This closure device may advance transluminal therapies by offering a secure, efficient method of hollow viscus closure.

Endoscopic full-thickness plication for the treatment of gastroesophageal reflux disease using multiple Plicator implants: 12-month multicenter study results

BACKGROUND

The full-thickness Plicator (Ethicon Endosurgery, Sommerville, NJ, USA) was developed for endoscopic treatment of gastroesophageal reflux disease (GERD). The goal is to restructure the antireflux barrier by delivering transmural pledgeted sutures through the gastric cardia. To date, studies using this device have involved the placement of a single suture to create the plication. The purpose of this study was to evaluate the 12-month safety and efficacy of this procedure using multiple implants to restructure the gastroesophageal (GE) junction.

METHODS

A multicenter, prospective, open-label trial was conducted at four tertiary centers. Eligibility criteria included symptomatic GERD [GERD Health-Related Quality-of-Life (GERD-HRQL) questionnaire, off of medication], and pathologic reflux (abnormal 24-h pH) requiring daily proton pump inhibitor therapy. Patients with Barrett's epithelium, esophageal dysmotility, hiatal hernia > 3 cm, and esophagitis (grade III or greater) were excluded. All patients underwent endoscopic full-thickness plication with linear placement of at least two transmural pledgeted sutures in the anterior gastric cardia.

RESULTS

Forty-one patients were treated. Twelve months post treatment, 74% of patients demonstrated improvement in GERD-HRQL scores by > or = 50%, with mean decrease of 17.6 points compared with baseline (7.8 vs. 25.4, p < 0.001). Using an intention-to-treat model, 63% of patients had symptomatic improvements of > or = 50%, with mean GERD-HRQL decrease of 15.0 (11.0 vs. 26.0, p < 0.001). The need for daily proton pump inhibitor (PPI) therapy was eliminated in 69% of patients at 12 months on a per-protocol basis, and 59% on an intention-to-treat basis. Adverse events included postprocedure abdominal pain (44%), shoulder pain (24%), and chest pain (17%). No long-term adverse events occurred.

CONCLUSIONS

Endoscopic full-thickness plication using multiple Plicator implants can be used safely and effectively to improve GERD symptoms and reduce medication use.

Endoscopic closure of gastrointestinal leaks

Surgery has been the mainstay of therapy in patients with gastrointestinal perforations. This paradigm started to shift with the development of techniques for endoscopic closure of gastrointestinal perforations. A detailed review of the literature on this subject, along with a commentary on practical aspects in the management of patients with gastrointestinal leaks, is provided here.

[Training design and improvement of technical skills in the transvaginal cholecystectomy (NOTES)]

INTRODUCTION

The current surgical scenario of the surgery through natural orifices or <<no-scar surgery>> requires acquiring new technical skills by the surgeon. We introduce the initial experience of the Minimally Invasive Surgery Centre Jesús Usón (MISCJU) in the design and setting-up of a surgical training programme using the the natural orifices approach for the acquisition of surgical skills and abilities, based on the preliminary trials in simulators and a pig model.

MATERIAL AND METHODS

After initial training, using a laparoscopic pelvic-trainer, 7 female pigs, with weights between 35-40 kg, were operated on. The transvaginal approach was completed using a one-channel gastroscope in all the animals. After accessing the abdomen, the abdominal cavity was explored, and the surgery was concluded with the endoscopic cholecystectomy.

RESULTS

Endoscopic cholecystectomy was successfully completed in 6 cases. In one of the animals, the procedure was stopped because of technical problems regarding the endoscope leaning to one end. The average surgical time was 107.14 min (range, 80-150 min). The transvaginal approach enabled the abdominal to be explored and the dissection, ligature and section of the cystic duct and the cystic artery. After cholecystectomy, the gallbladder was extracted through the vagina. After the procedure necropsy did not reveal intra-abdominal lesions or intraoperative complications.

CONCLUSIONS

The pure transvaginal cholecystectomy is a feasible and reproducible procedure in the animal model. A systematized training model, which includes physiopathology knowledge as well as technical knowledge, in order to translate these procedures to the clinical practice in a safe way, is needed.

Challenges and lessons learned from NOTES cholecystectomy initial experience: a stepwise approach from the laboratory to clinical application

BACKGROUND/PURPOSE

The initial idea behind natural orifice transluminal endoscopic surgery (NOTES) was that of an incisionless surgery. NOTES cholecystectomy is a good model of human ingenuity and technological advance. NOTES cholecystectomy in a human being was performed at our institution after extensive laboratory work in live pig models. In this process we gained helpful information related to NOTES cholecystectomy.

METHODS

More than 250 cholecystectomies in pigs have been performed. From May 2007 to November 2008 a total of 10 and 6 transvaginal and transgastric human cholecystectomies, respectively, have been performed.

RESULTS

The procedure was successful in all patients, with a mean operative time of 120 min. There were no intraoperative or postoperative complications. Patients recovered promptly after surgery and had minor postoperative pain. They were discharged on the second postoperative day.

CONCLUSIONS

The advantages of laparoscopy appeared to be enhanced by this approach: patients had minor postoperative pain and minimal scarring. This stepwise experience in the cholecystectomy procedure is an important first step in the development of methods and devices to enable the evaluation of potential incisionless NOTES surgery. Additional research and comparison studies are needed for further improvement in order to provide NOTES procedures to a wider range of patients.

NOTES: Transvaginal endoscopic cholecystectomy in humans-preliminary report of a case series

OBJECTIVES

Natural orifice translumenal endoscopic surgery (NOTES) represents an emerging technology, including under its umbrella a variety of approaches and combinations. The transvaginal approach to endoscopic cholecystectomy is one such technique, which we present here as a small series.

METHODS

From May to November 2007, a total of eight patients were scheduled to undergo transvaginal endoscopic cholecystectomy at our institute. Two patients were excluded as they were converted to laparoscopy due to technical difficulties.

RESULTS

Average age of the patients was 34.5 years, and mean body mass index was 27 kg/m(2). The mean operating time was 148.5 min. Patients were discharged in an average of four postoperative days. The major complication rate was 16% (1/6). The patient with a major complication had a subhepatic collection that was managed with ultrasonogram-guided aspiration followed by ERCP and stenting.

CONCLUSIONS

Since the first description of NOTES, there has been no standardized technique. In our technique, we used a single 3-mm trocar for visualizing the entry and exit of the endoscope, maintaining and measuring pneumoperitoneum, and retracting the gall bladder fundus. The instruments that were used were the conventional endoscopic ones. The transvaginal approach seems to be a viable alternative to the transgastric approach for cholecystectomy, as the transgastric approach has certain inherent problems like leakage from the gastrotomy site and poor ergonomy. The downside to the transvaginal approach is that it is possible only in women.

Novel technologies for natural orifice surgery: an overview

Natural Orifice Surgery (NOS) is now being elaborated with the aim to make abdominal surgery simpler and safer. The existing natural openings of the body are used for introduction of surgical instruments and thus to perform surgical procedures while avoiding to penetrate the abdominal wall. Actually, the transvaginal and transgastric approaches are the common routes used for NOS applications in humans. The transvaginal approach does not necessitate any sophisticated devices for opening and closure of the posterior colpotomy, thus being easy for the surgeon and safe for the patient. In contrast, the problem of transluminal access and closure represents significant obstacles in the transgastric approach and is still unsolved. In order to achieve this goal, various surgical prototype devices have been developed. This article aims to give an overview on the current status of techniques and technologies that are being developed and applied in conjunction with NOS procedures.

Technical feasibility of totally natural orifice cholecystectomy in a swine model

The goal of this study was to evaluate the feasibility of totally NOTES performing a cholecystectomy without laparoscopic assistance. A gastroscope was used through a transvaginal access in five acute female pigs. An incision of 2 cm was created in the vagina and pneumoperitoneum was obtained with a Veress needle. The gallbladder was located in the abdominal cavity using endoscopic transillumination for spatial orientation. After the abdominal suspension of the gallbladder the cholecystectomy was completed with the NOTES technique in four animals without complications. In one animal we had technical problems and the procedure was stopped. The mean operative time was 110 minutes. The transvaginal approach provides complete abdominal exploration and both the cystic duct and artery were identified, clipped, and transected. After dissection the gallbladder was removed through the vagina. Our results showed that completely transvaginal NOTES cholecystectomy is a feasible technique performed only with a flexible endoscope.

Comparison of transgastric access techniques for natural orifice transluminal endoscopic surgery

BACKGROUND

Different transgastric access techniques for natural orifice transluminal endoscopic surgery (NOTES) have been described.

OBJECTIVE

To evaluate different methods of transluminal access with regard to leak pressures after the procedure.

DESIGN AND SETTING

Experimental endoscopic study in an ex vivo porcine stomach model.

METHODS

The following endoscopic techniques for transgastric access were evaluated in 34 stomachs: (1) 1.5-cm to 2-cm linear incision, (2) balloon dilation after needle-knife puncture, (3) via a short submucosal tunnel, and (4) via an extended submucosal tunnel. For techniques 3 and 4, a submucosal tract was endoscopically created by physically separating the mucosa from the muscularis. Mucosal incisions were closed by the standardized application of clips. Handsewn gastric closure after a linear needle-knife incision served as a positive control, whereas, open 1.5-cm to 2-cm gastrotomies were negative controls. After the procedure, pressures to liquid leakage were recorded.

RESULTS

The unclosed controls demonstrated leakage at mean (SD) 2 +/- 2 mm Hg, which represents a baseline system resistance. The handsewn gastric closure after linear incision leaked at 50 +/- 7 mm Hg. The needle-knife gastrotomy, the balloon dilation, the short submucosal tunnel, and the extended submucosal tunnel leaked at 37 +/- 15 mm Hg, 41 +/- 24 mm Hg, 44 +/- 13 mm Hg, and 87 +/- 19 mm Hg, respectively. There were significant differences in leakage pressures between the group with the extended submucosal tunnel and all other transgastric access techniques (all P < or = .002).

CONCLUSIONS

The extended submucosal tunnel yielded the best leak resistance, which is superior to standard transgastric access methods and rival handsewn interrupted stitches.