Pure Natural Orifice Translumenal Endoscopic Surgery Research Articles

Advancing flexible endoscopy to natural orifice transluminal endoscopic surgery.

This review is an update on the recent advancements and clinical applications of flexible endoscopy in the context of natural orifice translumenal endoscopic surgery (NOTES). We focus on recent developments in gastrointestinal luminal and transluminal NOTES. NOTES has evolved from a hybrid approach utilizing a laparoscopic assistant to pure NOTES without laparoscopic assistance. Current experimental and clinical studies focus on the implementation of new minimally invasive approaches as well as on the training in the use of these procedures. In recent years, flexible endoscopic-NOTES and endoluminal surgery have increasingly reported favorable results in preclinical and experimental settings using flexible endoscopic cholecystectomy, cholecystolithotomy, and appendectomy. Additionally, flexible endoscopic lymphadenectomy and thyroidectomy are among the new interventions that are opening new frontiers for endoscopists to explore. Flexible endoscopy has paved way to new frontiers for endoscopists and surgeons. As the armamentarium of interventional endoscopy increases and the ability of endoscopists to perform advanced interventions safely fosters an inevitable step forward that will involve the integration of new technology with innovative thinking.

Per-oral endoscopic salpingo-oophorectomy (POESY) in humans: a prospective clinical feasibility study.

Natural orifice translumenal endoscopic surgery (NOTES) procedure describes a surgical approach using natural orifices. We describe a prospective non-comparative clinical study on transgastric salpingo-oophorectomy in humans. Patients with indication for salpingo-oophorectomy were offered the transgastric approach. This paper presents the data of the first 6 patients, in whom the procedure was performed. After gastroscopic incision in the anterior corpus wall we advanced the flexible gastroscope into the abdominal cavity. With the help of a transvaginally introduced 10mm trocar and, if the uterus was present, an intrauterine manipulator, the salpingo-oophorectomy was performed. The colpotomy was dilated and the specimens were extracted in a bag. The gastrotomy was closed with an over-the-scope-clip and the colpotomy with a running suture. The planned salpingo-oophorectomy was performed successfully in all patients. All patients recovered quickly and were discharged between the third and fifth day. In one patient a gastric bleeding was seen on the first postoperative day. The bleeding was clipped gastroscopically, all other follow ups were uneventful. Our study demonstrates the feasibility of the transgastric access to the pelvis. The gastroscope provided excellent optical control and good tissue preparation. Therefore, we conclude that pure NOTES procedures using the transgastric access to the adnexa are feasible. An increasing role of transgastric procedures for diseases in the pelvic region can be expected in particular if new endoscopic platforms with better means of instrumentation and tissue management become available.

Pure retroperitoneal natural orifice translumenal endoscopic surgery (NOTES) transvaginal nephrectomy using standard laparoscopic instruments: a safety and feasibility study in a porcine model.

BackgroundAmong the different organs used for NOTES (natural orifice translumenal endoscopic surgery) technique, the transvaginal approach may be the optimal choice because of a simple and secure closure of colpotomy site. Pure and hybrid NOTES transvaginal operations were routinely performed via transperitoneal access. In this study, we investigate the safety and feasibility of pure retroperitoneal natural orifice translumenal endoscopic surgery (NOTES) transvaginal nephrectomy using conventional laparoscopic techniques in a porcine model.MethodsSix female pigs, weighing an average of 30 kg, were used in this study. Under general anesthesia, pure retroperitoneal NOTES transvaginal nephrectomy was conducted using standard laparoscopic instruments. Posterolateral colpotomy was performed, and the incision was enlarged laterally using blunt dissection and pneumatic dilation. A single-port device was inserted to construct the operative channel. The retroperitoneal space was created using sharp and blunt dissection under endoscopic guidance up to the level of the kidney. Dissection and removal of the kidney were performed according to standard surgical procedure, and the colpotomy site was closed using interrupted sutures. The survival and complications were observed 1 week postoperatively.ResultsOur results showed that two cases failed because of peritoneal rupture. One case was successful, but required the assistance of an extra 5 mm laparoscopic trocar inserted in the flank. Three cases of pure retroperitoneal NOTES transvaginal nephrectomy were completed, and survived 1 week after the operation. In these three cases, no intra- or postoperative complications were observed.ConclusionsAll findings confirmed the safety and feasibility of the retroperitoneal pure retroperitoneal NOTES transvaginal nephrectomy using standard laparoscopic instruments, which suggested the possibility of clinical application in human beings in the future.

Development of a Haptic Interface for Natural Orifice Translumenal Endoscopic Surgery Simulation.

Natural orifice translumenal endoscopic surgery (NOTES) is a minimally invasive procedure, which utilizes the body's natural orifices to gain access to the peritoneal cavity. The NOTES procedure is designed to minimize external scarring and patient trauma, however flexible endoscopy based pure NOTES procedures require critical scope handling skills. The delicate nature of the NOTES procedure requires extensive training. Thus, to improve access to training while reducing risk to patients, we have designed and developed the VTEST, a virtual reality NOTES simulator. As part of the simulator, a novel decoupled 2-DOF haptic device was developed to provide realistic force feedback to the user in training. A series of experiments were performed to determine the behavioral characteristics of the device. The device was found capable of rendering up to 5.62N and 0.190Nm of continuous force and torque in the translational and rotational DOF, respectively. The device possesses 18.1 and 5.7Hz of force bandwidth in the translational and rotational DOF, respectively. A feedforward friction compensator was also successfully implemented to minimize the negative impact of friction during the interaction with the device. In this work, we have presented the detailed development and evaluation of the haptic device for the VTEST.

Natural orifice translumenal endoscopic surgery (NOTES): emerging trends and specifications for a virtual simulator.

A virtual translumenal endoscopic surgical trainer (VTEST) is being developed to accelerate the development of natural orifice translumenal endoscopic surgery (NOTES) procedures and devices in a safe and risk-free environment. For a rapidly developing field such as NOTES, a needs analysis must be conducted regularly to discover emerging research trends and areas of potential high impact for a virtual simulator. This paper presents a survey-based study which follows a similar study conducted by this group in 2011 (Sankaranarayanan et al. in Surg Endosc 27:1607-1616, 2013). A 32-point questionnaire was distributed at the 2012 Natural Orifice Surgery Consortium for Assessment and Research annual meeting. These data were subsequently augmented by an identical online survey, targeted at the members of the American Society for Gastrointestinal Endoscopy and the Society of American Gastrointestinal and Endoscopic Surgeons, and analyzed. Twenty-eight NOTES experts participated in the 2012 study. Cholecystectomy (CE) procedure remained the most commonly performed NOTES technique, with 18 positive responses (64%). In contrast to 2011, the popularity of the NOTES appendectomy (AE) was significantly lower, with only 2 (7%) instances (CE vs. AE, p < 0.001), while the number of peroral endoscopic myotomy (POEM, PE) cases had increased significantly, with 11 (39%) positive responses, respectively (PE vs. AE, p = 0.013). Strong preference toward hybrid rather than pure NOTES techniques (82 vs. 11%, p < 0.001) was also expressed. Other responses were similar to those in the 2011 study, with the VTEST™ utility in developing and testing new techniques and instruments ranked particularly high. Based on the results of this study, a decision was made to focus exclusively on the transvaginal hybrid NOTES cholecystectomy procedure, including both rigid and flexible scope techniques. The importance of developing a virtual NOTES simulator was reaffirmed, with POEM identified as a promising candidate for future simulator development.

Transanal colorectal resection using natural orifice translumenal endoscopic surgery (NOTES)

The surgical management of rectal cancer has evolved over the past century, with total mesorectal excision (TME) emerging as standard of care. As a result of the morbidity associated with open TME, minimally invasive techniques have become popular. Natural orifice translumenal endoscopic surgery (NOTES) has been held as the next revolution in surgical techniques, offering the possibility of 'incisionless' TME. Early clinical series of transanal TME with laparoscopic assistance (n = 72) are promising, with overall intraoperative and postoperative complication rates of 8.3% and 27.8%, respectively, similar to laparoscopic TME. The mesorectal specimen was intact in all patients, and 94.4% had negative margins. There was no oncological recurrence in average-risk patients at short-term follow up, and 2-year survival rates in high-risk patients were comparable to that after laparoscopic TME. These preliminary studies demonstrate transanal NOTES TME with laparoscopic assistance to be clinically feasible and safe given careful patient selection, surgical expertise, and appropriate procedural training. We are hopeful that with optimization of transanal instruments and surgical techniques, pure transanal NOTES TME will become a viable alternative to open and laparoscopic TME in the future.

Natural-orifice Translumenal Endoscopic Surgery (NOTES)

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.

Evaluation of bacterial contamination after “pure” (totally) transvaginal NOTES® diagnostic peritoneoscopy with biopsies in swine: a comparative study with laparoscopy

Bacterial contamination from viscerotomy is a barrier to natural orifice translumenal endoscopic surgery (NOTES). The aim of this survival study is to evaluate pure (totally) transvaginal NOTES bacterial contamination compared with laparoscopy in pigs. Twelve adult female pigs underwent peritoneoscopy with liver and peritoneal biopsies, using either laparoscopy (Glap, six animals) or pure transvaginal (GNOTES) access, and were maintained alive for 7 days. In all animals, blood cultures were taken at baseline, and after 24 h and 7 days postoperatively. Swab cultures from vagina (GNOTES) and skin (Glap) were obtained pre- and post-antisepsis. Peritoneal fluid culture was obtained at necropsy. For statistical analysis, Glap and GNOTES were compared for presence of positive bacterial cultures (qualitative bacterial analysis) using Fisher's test, with level of significance set at p < 0.05. All animals had good postoperative outcome. One animal had transient perioperative bleeding from a transvaginal access. Two animals in Glap and one in GNOTES had positive blood cultures after the procedure. All animals from GNOTES and Glap presented with mixed flora pre-antisepsis. After antisepsis, one animal (GNOTES) presented with a positive vaginal swab culture (a single bacterial strain was identified). There was no positive skin swab culture in Glap. There were no signs of intra-abdominal infection at necropsy. In two animals, one from Glap and another from GNOTES, intra-abdominal culture was positive for Corynebacterium spp. and Escherichia coli, respectively. There was no correlation between the bacterial flora found at the access site and in the peritoneal cultures. Pure transvaginal peritoneoscopy with liver and peritoneal biopsy in swine is feasible and associated with bacterial contamination comparable to laparoscopy. Peritoneal bacterial contamination was clinically insignificant after 1 week postoperatively. Preoperative antisepsis provided significant reduction of bacterial load prior to transvaginal and laparoscopic procedures.

Transvaginal Sigmoid Cancer Resection: First Case with 12 Months of Follow-Up—Technique Description

Several minimally invasive techniques using natural orifices as an entrance site to the peritoneal cavity have been described recently. Pure natural orifice translumenal endoscopic surgery (NOTES) techniques have been mainly implemented to perform cholecystectomies and appendectomies, while more complex operations like colon resections have been described in a hybrid setting and with the use of the transumbilical approach. Here we describe the technique of transvaginal sigmoid colon resection for cancer with standard laparoscopy equipment. After developing the transvaginal technique of sigmoid colon resection in an experimental sheep model, we have performed this operation in a human patient for cancer. Twelve months of follow-up is reported. A totally transvaginal R0 resection of the sigmoid colon for adenocarcinoma has been successfully performed in a female patient with laparoscopy equipment. The specimen included 13 lymph nodes, all of which were free of metastasis. Twelve months after surgery the patient is alive with no evidence of disease. A pure transvaginal NOTES approach to sigmoid colon cancer is feasible in human patients.

Minilaparoscopy-assisted natural orifice total colectomy: technical report of a minilaparoscopy-assisted transrectal resection

Experimental experience and the technological evolution of minimally invasive surgical devices have allowed initial reports describing the clinical applicability of natural orifice translumenal endoscopic surgery (NOTES). Colorectal resections are an interesting target for the NOTES platform. Theoretically, the transrectal approach could overcome the proposed limitations of transvaginal access, increasing NOTES clinical applicability. Hybrid procedures such as minilaparoscopy-assisted natural orifice surgery (MA-NOS) are the safe progression to pure NOTES. This report describes the first clinical case of a transrectal MA-NOS total colectomy. The patient was a 36-year-old man with severe ulcerative colitis (UC) who experienced failure of immunosuppressive therapy. The standard steps of laparoscopic total colectomy were respected, with basic triangulation maintained throughout the case. A transrectal endoscopic device was used for optic assistance, colon dissection, ileum section, and specimen retrieval. Transrectal MA-NOS total colectomy was assisted by three laparoscopic ports: a 12-mm port used as the terminal ileostomy site, a 2-mm needle epigastric port, and a 5-mm umbilical port used as a drain site at the final intervention. No intraoperative complications occurred. The total operative time was 240 min. Oral intake was initiated on postoperative day 2. Because of UC rectal activity, a course with azathioprine was completed, and the patient was discharged receiving 1 g of rectal mesalazine for maintenance. The final pathology demonstrated pancolonic inflammatory bowel disease in the form of UC with severe activity. Transrectal MA-NOS total colectomy was feasible and safe in the reported case. Improvement in NOTES instrumentation and selective clinical applications are mandatory before clinical trials.

Natural Orifice Translumenal Endoscopic Surgery in Humans: A Review

Natural orifice translumenal endoscopic surgery (NOTES) had its origins in numerous small animal studies primarily examining safety and feasibility. In human trials, safety and feasibility remain at the forefront; however, additional logistic, practical, and regulatory requirements must be addressed. The purpose of this paper is to evaluate and summarize published studies to date of NOTES in humans. The literature review was performed using PUBMED and MEDLINE databases. Articles published in human populations between 2007 and 2011 were evaluated. A review of this time period resulted in 48 studies describing procedures in 916 patients. Transcolonic and transvesicular procedures were excluded. The most common procedure was cholecystectomy (682, 75%). The most common approach was transvaginal (721, 79%). 424 procedures (46%) were pure NOTES and 491 (54%) were hybrid NOTES cases. 127 (14%) were performed in the United States of America and 789 (86%) were performed internationally. Since 2007, there has been major development in NOTES in human populations. A preponderance of published NOTES procedures were performed internationally. With further development, NOTES may make less invasive surgery available to a larger human population.

Update on Transanal NOTES for Rectal Cancer: Transitioning to Human Trials

The feasibility of natural orifice translumenal endoscopic surgery (NOTES) resection for rectal cancer has been demonstrated in both survival swine and fresh human cadaveric models. In preparation for transitioning to human application, our group has performed transanal NOTES rectal resection in a large series of human cadavers. This experience both solidified the feasibility of resection and allowed optimization of technique prior to clinical application. Improvement in specimen length and operative time was demonstrated with increased experience and newer platforms. This extensive laboratory experience has paved the way for successful clinical translation resulting in an ongoing clinical trial. To date, based on published reports, 4 human subjects have undergone successful hybrid transanal NOTES resection of rectal cancer. While promising, instrument limitations continue to hinder a pure transanal approach. Careful patient selection and continued development of new endoscopic and flexible-tip instruments are imperative prior to pure NOTES clinical application.

Natural orifice translumenal endoscopic surgery applications in clinical practice

To review natural orifice translumenal endoscopic surgery (NOTES) applications in clinical practice and assess the evidence base for each application as reported in the literature. An electronic literature search was performed. Inclusion criteria were publications relating to NOTES applications in humans. For each type of operation the highest level of evidence available for clinical NOTES publications was evaluated. Morbidity and short-term operative outcomes were compared with gold standard published evidence where available. Finally, registered trials recruiting patients for NOTES applications were identified. Human NOTES publications with the highest level of evidence in each application are identified. There were no RCTs in the literature to date. The strongest evidence came in the form of large, multi-centre trials with 300-500 patients. The results are encouraging, comparable with gold standard techniques on morbidity and mortality. While short-term operative outcomes were also similar when compared to the gold standard techniques, other than improved cosmesis little else can definitely be concluded as a clear benefit of a NOTES procedure. The most common procedures are cholecystectomy, appendicectomy and peritoneoscopy mainly performed via transvaginal access. It is evident that morbidity appears to be higher when the transgastric route is used. The safety profile of hybrid NOTES transvaginal procedures is beginning to be confirmed as is evident from the large number of procedures presented in this review. A number of authors have presented work on pure NOTES procedures but the results are inconsistent and thus the vast majority of NOTES procedures worldwide are performed in a hybrid fashion with a variable amount of laparoscopy. This review of the clinical applications of NOTES summarises the growing evidence behind this surgical discipline and highlights NOTES procedures with an acceptable safety profile.

Pure transvesical NOTES uterine horn resection in swine as an appendectomy model

Because of size limitation, the lack of reliable instruments, and bladder closure methods, transvesical natural orifice translumenal endoscopic surgery (NOTES) is still in its infancy. The porcine uterine horn is similar to the human vermiform appendix. Therefore, the resection of the porcine uterine horn is an established animal model for the human appendectomy. In this study, we evaluated the feasibility of a pure transvesical NOTES approach to uterine horn resection in a porcine model. We performed five operations on three female pigs (30-35 kg) under general anesthesia in the Trendelenburg position. The laparoscope at the umbilicus was used only for the purpose of documentation. We used a rigid ureteroscope and a customized access system that prevented gas leakage and facilitated in-and-out passage of the instruments. A vesicostomy was created on the posterolateral bladder wall by using a needle knife through the channel of the ureteroscope. The uterine horn resection was performed by using an electric needle knife, hot forceps, and a polypectomy snare through the access system placed in vesicostomy. Bladder closure was performed with extracorporeal ties using metal clip tagged threads and a knot-pusher. We successfully performed the pure transvesical NOTES uterine horn resections. The mean total operative time was 141.8 (± 58.7) min, and blood loss was minimal in all cases. No leakage was observed at the bladder repair sites after filling with normal saline. The removed uterine horns were approximately 6-12-cm long and 0.6-0.8 cm in diameter. On final inspection, the urethras were not damaged. This study demonstrates the feasibility of a pure transvesical NOTES uterine horn resection in a porcine model. To the best of our knowledge, this is the world's first report on a pure transvesical NOTES with a therapeutic purpose. This study shows the potential for adoption of the transvesical approach in NOTES procedures.

Totally transvaginal resection of the descending colon in an experimental model

Natural orifice translumenal endoscopic surgery (NOTES), although in its embryonic phase, is currently experiencing important developments. The technique has been successfully applied for cholecystectomies and appendectomies. However, several doubts exist as to the technical limitations and feasibility of NOTES in other clinical settings. The authors have performed totally transvaginal colon resections in a sheep model. Although completion of the surgery was possible through the transvaginal route, the addition of a transumbilical laparoscope was used as an added safety measure. Totally transvaginal resection of the sigmoid colon was performed for two sheep with no intra- or postoperative complications. Totally transvaginal resection of the colon (pure NOTES) is feasible in a sheep model.

NOTES transanal rectal cancer resection using transanal endoscopic microsurgery

BACKGROUND: With a rapidly expanding international registry of cases, Natural Orifice Translumenal Endoscopic Surgery (NOTES) continues to be held as the next phase in minimally invasive surgery. While pure and hybrid transvaginal procedures predominate clinically, there is growing interest in transanal NOTES as it may potentially minimize the morbidity of colorectal resections. METHODS: Extensive experimental and clinical evidence support the fact that septic complications from intentional colotomy during colorectal procedures are minimized with adequate closure. Other advantages of transanal NOTES include the favorable ergonomics of transanal endoscopy and availability of Transanal Endoscopic Microsurgery (TEM) as a particularly well-suited endoscopic platform. RESULTS: Since the description of transanal endoscopic rectosigmoid resection using TEM in 2007, extensive evaluation in swine acute and survival studies has demonstrated that this technique is feasible, safe, and easily reproducible using conventional instrumentation. Validation of this approach in human cadavers has confirmed the feasibility of transanal total mesorectal excision using a standardized technique. In the first clinical report published to date, transanal endoscopic rectosigmoid resection with TME was performed using laparoscopic assistance in a female patient with a stage III mid-rectal cancer treated with neoadjuvant therapy. CONCLUSIONS: Although preliminary, these results highlight the potential impact of this approach in minimizing the morbidity associated with rectal cancer resection, and warrant further investigation with respect to safety and long-term oncologic outcomes. Improvements in the design of currently available endoscopic platforms and instrumentation will be important for widespread clinical application in the future, and if pure NOTES transanal resection remains the ultimate goal.

Current status and prerequisites for natural orifice translumenal endoscopic surgery (NOTES)

Natural orifice translumenal endoscopic surgery (NOTES) is a sophisticated form of endoscopic surgery whose use has recently spread rapidly around the world. Although hundreds of reports of animal studies and clinical cases about NOTES have been published since 2004, NOTES is still in the experimental phase. The formation of an iatrogenic incision in the lumenal wall of intraperitoneal organs is a major disadvantage of NOTES. No reliable technique for complete closure has yet been established, and this problem must be resolved before NOTES can be adopted as a routine clinical practice. Several devices for the closure of lumenal incisions in the stomach or colorectum have been developed, and their safety and usefulness have been examined in animal studies and clinical cases. Kyushu University has been involved in furthering the adoption of NOTES as a routine clinical practice, and the Kyushu University Training Center for Minimally Invasive Surgery holds training sessions on endoscopic surgical techniques for surgeons from all over Japan. Studies to develop a navigation system and robotic technology for use with NOTES are also in progress at Kyushu University. The further development of endoscopy-related technologies and equipment, such as robotic technology, is therefore essential to allow the safe, widespread adoption of pure NOTES.

Getting ready for surgery through natural orifice

Abstract The technical background of pure Natural Orifice Translumenal Endoscopic Surgery (NOTES) surgery has not been created yet, but ever more reports are being published on hybrid NOTES surgery and single-port surgical interventions, which have appeared as a result of device development inspired by NOTES. Surgery carried out through single ports only differ from pure NOTES in respect of the access orifice, which makes learning this technique extremely important for anyone whishing to implement a surgical intervention through a natural orifice. Numerous publications have appeared by now on the single port or hybrid NOTES surgery of various organs (gall bladder, kidney, large bowel). Based on these, most surgery is safely feasible through one port as well, but the surgery takes longer and it is not significantly less painful than a “traditional” laparoscopic intervention. Long-term results are still missing, primarily in what concerns the frequency of infections and post-operative hernia. We have received an answer to part of the dilemmas formulated in the White Paper. Besides specially bent laparoscopic devices robot technology and devices controlled by extracorporal magnets may both be a solution to the problem of triangulation. The transvaginal and transgastric paths do not seem to cause significant risks from the viewpoint of infections, but the closing of viscerotomy in the case of the stomach is far from being solved. In respect of learning and practicing new surgical techniques no method exists at the moment that could be considered the “gold standard”. Besides the earlier questions there are new ones as well awaiting partial solutions (e.g. necessity of drain following a NOTES surgery, oncologic principles).

Endoscopic transgastric pure NOTES cholecystectomy with naso‐gallbladder drainage tube placement and injection of a hyaluronic acid mixture (with Video)

Endoscopic transgastric pure natural orifice translumenal endoscopic surgery (NOTES) cholecystectomy is a difficult procedure, and most human female cases are performed as hybrid NOTES, using a transvaginal route. We tried a transgastric pure NOTES procedure without laparoscopic procedure in an animal study after placing an endoscopic naso-gallbladder drainage (ENGBD) tube and injecting a hyaluronic acid (HA) mixture. We performed the method in four pigs, using a standard single-channel endoscope. The ENGBD tube was placed first and the HA mixture was injected between the gallbladder (GB) serosa and liver bed. We determined the gastrotomy site using an ENGBD tube, which made the GB approach easy under fluoroscopic guidance. The scope was not retroflexed, but was rotated at the stomach fornix. The connecting tissues between the GB serosa and liver bed expanded following the injection of the HA mixture, facilitating GB removal with a Hook knife. The GB wall, liver, and vessels were observed clearly during the procedure, and there were no incorrect cuts. We successfully performed a transgastric pure NOTES cholecystectomy in pigs. An ENGBD tube was useful as a guide to the GB, and for recognizing the cystic duct, and injecting the HA mixture facilitated the GB dissection.

Per-oral dual scope NOTES cholecystectomy in porcine model (with video)

Several working groups have already demonstrated the feasibility of transgastric surgery procedures using flexible endoscopes. However, technical limitations in natural orifice translumenal endoscopic surgery (NOTES) (e.g., exposure, retraction, insufflations, and triangulation) currently still require the use of at least one external instrument. Therefore, "pure NOTES" transgastric cholecystectomy has not yet been described. The authors successfully performed "pure NOTES" transgastric cholecystectomy using a transoral dual-scope technique (similar to the approach the authors previously reported for gastric closure) that allows completion of the procedure by pure NOTES without an external instrument. With the subject under general anesthesia, a double-channel gastroscope (Storz®, Tuttlingen, Germany) passed by mouth entered the peritoneum through the distal anterior gastric wall. The most ideal site for a second gastric exit was then selected for another single-channel scope. With the gallbladder retracted by the assistant operating the double-channel scope, retrograde cholecystectomy was performed by the primary surgeon using the single-channel scope. Four animals were killed immediately to study the quality of the operative dissection, whereas the other four pigs were kept alive. The gastrotomy was closed using a 27- to 30-mm cardiac septal occluder (Occlutech®, GmbH, Jena, Germany) according to a previously described method. The postoperative follow-up assessment of these animals included laparoscopy and necropsy 2 weeks later. All the cholecystectomies were immediately successful without any intraoperative complication. Scope withdrawal caused no injuries to the esophagus or pharynx. Although no overt postoperative complication was evident, two surviving pigs had signs of minor peritoneal infection. This study investigated "pure NOTES" transgastric cholecystectomy using tentative experimentation to overcome the "retraction" and "triangulation" issues and to realize a "pure NOTES" operation. The use of two endoscopes with selected differentiation of their gastric placements compensated for the lack of triangulation and retraction.