Orifice Transluminal Endoscopic Surgery Procedures Research Articles

What is the applicability of tubal ligation with the vaginal natural orifice transluminal endoscopic surgery technique and its value in patient comfort?

The aim of this study was to observe the feasibility of the tubal/adnexal approach using vaginal natural orifice transluminal endoscopic surgery and compare its contribution with surgeon ergonomics and postoperative patient comfort with that of conventional laparoscopy. We completed this study retrospectively with 47 patients. Patients were followed at their postoperative first month. We analyzed the usability of the vaginal natural orifice transluminal endoscopic surgery method over conventional laparoscopy by comparing the demographics, surgical data, and postoperative findings collected between the two groups. Patients in the conventional laparoscopy group were older (39.1±3.3 years) than those in the vaginal natural orifice transluminal endoscopic surgery patient group (p=0.005). Pain intensity 24 h after surgery was lower in the vaginal natural orifice transluminal endoscopic surgery group (p=0.003), while sexual function and dyspareunia did not differ between the two groups in the first month. Patients in the vaginal natural orifice transluminal endoscopic surgery group were more relieved about painlessness and the comfort it brought than the conventional laparoscopy group (p=0.027, χ2=12.56). Patients subjected to the vaginal natural orifice transluminal endoscopic surgery procedure showed higher levels of satisfaction, less postoperative pain, and greater comfort than those subjected to conventional laparoscopy.

Master-slave Control Strategy of Surgical Robots for Gastrointestinal Surgery

The precise construction of the master-slave control strategy is a fundamental requirement for robot-assisted surgery. In this study, we propose a master-slave control strategy for gastrointestinal surgical robots based on the natural orifice transluminal endoscopic surgery surgical robot developed by Tianjin University. The forward and inverse kinematics of the continuum mechanism at the slave manipulator are investigated. A master-slave coordinate mapping system for surgical robots is established by analyzing the kinematic characteristics of the master and slave manipulators. Additionally, an intuitive mapping algorithm and a control flowchart for the robot are developed. The proportional control and incremental control strategies tailored for natural orifice transluminal endoscopic surgery procedures are proposed based on intuitive mapping control. Finally, a master-slave trajectory tracking experiment is performed to validate the feasibility of the proposed master-slave control strategy.

MemoBox: A mechanical follow-the-leader system for minimally invasive surgery

With the increase in Natural Orifice Transluminal Endoscopic Surgery procedures, there is an increasing demand for surgical instruments with additional degrees of freedom, able to travel along tortuous pathways and guarantee dexterity and high accuracy without compromising the surrounding environment. The implementation of follow-the-leader motion in surgical instruments allows propagating the decided shape through its body and moving through curved paths avoiding sensitive areas. Due to the limited operational area and therefore the instrument size, the steerable shaft of these instruments is usually driven by cables that are externally actuated. However, a large number of degrees of freedom requires a great number of actuators, increasing the system complexity. Therefore, our goal was to design a new memory system able to impose a follow-the-leader motion to the steerable shaft of a medical instrument without using actuators. We present a memory mechanism to control and guide the cable displacements of a cable-driven shaft able to move along a multi-curved path. The memory mechanism is based on a programmable physical track with a mechanical interlocking system. The memory system, called MemoBox, was manufactured as a proof-of-concept demonstration model, measuring 70 mm × 64 mm × 6 mm with 11 programmable elements and featuring a minimum resolution of 1 mm. The prototype shows the ability to generate and shift complex 2D pathways in real-time controlled by the user.

Transvaginal laparoscopic salpingo-oophorectomy: an oncological risk-reducing procedure.

Aim:Since the first natural orifice transluminal endoscopic surgery procedure, renewed interest has arisen in further developing and advancing minimal access surgery. We introduce a natural orifice endoscopic approach for a bilateral salpingo-oophorectomy.Patients & methods:Using the vagina as a natural orifice, we performed a transvaginal laparoscopic salpingo-oophorectomy to remove bilateral adnexa in patients with a strong family history of ovarian and/or breast cancer and those positive for BRCA1/2 mutation.Results:Total 36 women underwent transvaginal laparoscopic salpingo-oophorectomy. Conversion to routine laparoscopy was required in eight patients to complete the operation. No peri-operative complications were noted.Conclusion:We describe a novel approach in gynecological surgery. Our technique proved to be safe and efficient with the advantage of avoiding any abdominal scars.

Submucosal tunnel endoscopy: Peroral endoscopic myotomy and peroral endoscopic tumor resection.

Peroral endoscopic myotomy (POEM) is an innovative, minimally invasive, endoscopic treatment for esophageal achalasia and other esophageal motility disorders, emerged from the natural orifice transluminal endoscopic surgery procedures, and since the first human case performed by Inoue in 2008, showed exciting results in international level, with more than 4000 cases globally up to now. POEM showed superior characteristics than the standard 100-year-old surgical or laparoscopic Heller myotomy (LHM), not only for all types of esophageal achalasia [classical (I), vigorous (II), spastic (III), Chicago Classification], but also for advanced sigmoid type achalasia (S1 and S2), failed LHM, or other esophageal motility disorders (diffuse esophageal spasm, nutcracker esophagus or Jackhammer esophagus). POEM starts with a mucosal incision, followed by submucosal tunnel creation crossing the esophagogastric junction (EGJ) and myotomy. Finally the mucosal entry is closed with endoscopic clip placement. POEM permitted relatively free choice of myotomy length and localization. Although it is technically demanding procedure, POEM can be performed safely and achieves very good control of dysphagia and chest pain. Gastroesophageal reflux is the most common troublesome side effect, and is well controllable with proton pump inhibitors. Furthermore, POEM opened the era of submucosal tunnel endoscopy, with many other applications. Based on the same principles with POEM, in combination with new technological developments, such as endoscopic suturing, peroral endoscopic tumor resection (POET), is safely and effectively applied for challenging submucosal esophageal, EGJ and gastric cardia tumors (submucosal tumors), emerged from muscularis propria. POET showed up to know promising results, however, it is restricted to specialized centers. The present article reviews the recent data of POEM and POET and discussed controversial issues that need further study and future perspectives.

Transvaginal organ extraction: potential for broad clinical application

Natural orifice transluminal endoscopic surgery procedures have evolved over the past few years. A transvaginal approach is a promising alternative for intraperitoneal procedures. Our objective was to evaluate the safety and feasibility of transvaginal organ extraction. This institutional review board-approved protocol involved retrospective review of an ongoing prospective study. Female subjects who presented to our hospital for elective cholecystectomy, appendectomy, or sleeve gastrectomy were offered participation in the study. Eligible patients met the following criteria: age between 18 and 75, diagnosis of gallbladder disease, acute appendicitis, or morbid obesity who desired surgical treatment. A hybrid transvaginal natural orifice approach was used in this series. Thirty-four women underwent transvaginal organ extraction between September 2007 and January 2012. The mean age was 40±12.1years (range 23-63years). The mean body mass index was 27±6.4kg/m(2) (range 16-43kg/m(2)). All patients had an American Society of Anesthesiologists classification of two or below. The mean operative time for cholecystectomy, appendectomy, and sleeve gastrectomy was 90, 71, and 135min, respectively. There were no conversions to open operation and no intraoperative complications. The mean hospital stay was 2days for all cases. Patients were followed for a mean of 24months (range 1-61months). There were two pregnancies and two successful vaginal deliveries. Six patients (18%) had minor complaints of spotting or heavy menses in the immediate postoperative period that resolved with conservative measures. There were no abdominal wall complications. There were no long-term complications and no mortalities. This initial experience suggests that this surgical approach is safe, does not increase length of stay, and has no long-term vaginal complications. Given this attractive profile, a transvaginal approach may prove to be a superior mode of organ extraction, although randomized studies and long-term follow-up are needed.

Pure Transvaginal Ventral Hernia Repair in Humans

Transvaginal natural orifice transluminal endoscopic surgery procedures are at the forefront of minimally invasive innovation, remarkable for shorter recovery times and decreased postoperative pain. We aim to demonstrate a novel technique of pure transvaginal laparoscopic ventral hernia repair in a series of patients performed in our institution. The patient was placed in lithotomy position and steep Trendelenburg. A 2-cm transverse colpotomy incision was made and a SILS port was introduced. One 12-mm trocar and two 5-mm trocars were placed through the SILS port and standard straight laparoscopic instruments were used. An appropriately sized round mesh was deployed within a specimen retrieval bag into the peritoneal cavity. Complete anterior circumferential fixation of the mesh was achieved using an AbsorbaTack device. The colpotomy incision was closed. There were a total of 6 pure transvaginal ventral hernia repair procedures performed in our institution between November 2010 and February 2012. The first case was converted to an open procedure after a rectal injury was recognized and repaired. Two patients had transient urinary retention that resolved after 24 hours. One patient had vaginal wound granulation noted at 2 months postoperatively. No long-term complications or recurrences were noted with a median follow-up of 9 months. The mean operative time was 107 minutes. Our initial experience with transvaginal ventral hernia repair in humans suggests that this procedure is feasible, safe, and associated with improved cosmetic results.

Recent advances of natural orifice transluminal endoscopic surgery in urological surgery

Natural orifice transluminal endoscopic surgery designates a surgical procedure that utilizes one or more patent natural orifices of the body with the intention to puncture a hollow viscera in order to enter the abdominal cavity. First carried out at the beginning of the 2000s in experimental models, it can be considered the natural evolution of laparoscopy towards the ideal of scarless surgery, as the avoidance of a large abdominal scar is associated with better cosmetic results and better recovery. However, the technology currently available does not allow the performance of complete pure natural orifice transluminal endoscopic surgery procedures. The surgical tools used are not specially designed for this approach, so difficulties in retracting organs, bleeding control and clashing of instruments are the main obstacle surgeons face. For this reason, the current available technique is the so-called hybrid approach, where a natural orifice approach is combined with some abdominal trocars, using the natural orifice as the exit door for the specimen removal. As not many comparative studies have been published evaluating the advantages of natural orifice transluminal endoscopic surgery in front of traditional laparoscopic surgery, a review of the history of natural orifice transluminal endoscopic surgery, and an assessment of the available evidence of this technique regarding renal and urological pelvic surgery are performed in this article.

Natural Orifice Transluminal Endoscopic Surgery and Upper Gastrointestinal Tract

Since the first transgastric natural orifice transluminal endoscopic surgery was described, various applications and modified procedures have been investigated. Transgastric natural orifice transluminal endoscopic surgery for periotoneoscopy, cholecystectomy, and appendectomy all seem viable in humans, but additional studies are required to demonstrate their benefits and roles in clinical practice. The submucosal tunneling method enhances the safety of peritoneal access and gastric closure and minimizes the risk of intraperitoneal leakage of gastric air and juice. Submucosal tunneling involves submucosal tumor resection and peroral endoscopic myotomy. Peroral endoscopic myotomy is a safe and effective treatment option for achalasia, and the most promising natural orifice transluminal endoscopic surgery procedure. Endoscopic full-thickness resection is a rapidly developing natural orifice transluminal endoscopic surgery procedure for the upper gastrointestinal tract and can be performed with a hybrid natural orifice transluminal endoscopic surgery technique (combining a laparoscopic approach) to overcome some limitations of pure natural orifice transluminal endoscopic surgery. Studies to identify the most appropriate role of endoscopic full-thickness resection are anticipated. In this article, I review the procedures of natural orifice transluminal endoscopic surgery associated with the upper gastrointestinal tract.

Prospective evaluation of spiral overtube–assisted ERCP in patients with surgically altered anatomy

exposure, smoking, and other factors have been implicated. It certainly is possible that these ulcerations are multifactorial in etiology. Many ulcerations heal with proton pump inhibitor therapy and sucralfate, and if the etiology was purely ischemic, this would likely not be effective. However, in a significant minority of ulcer patients, medical therapy is not adequate. This procedure does not address underlying ischemia; however, covering the lesion by folding the ulcer bed (submucosa to submucosa) onto itself may protect it from exposure to irritating gastric pouch contents, removing one contributing factor and increasing the chance for healing to occur. Limitations of this study are the small sample size and single center design. In addition, the generalizability of this study is limited, although it may initially extend to the treatment of bleeding ulcerations that are not amenable to traditional endoscopic therapies. Additionally, the device may be useful in various developing natural orifice surgery and natural orifice transluminal endoscopic surgery procedures in which a user-friendly, flexible suturing device is needed. Further studies are ongoing. In summary, this pilot study demonstrates the technical feasibility, safety, and efficacy of peroral endoscopic suturing in the treatment of recalcitrant marginal ulceration. These preliminary results suggest that this technique may provide an effective, minimally invasive alternative to ul-

Endoscopic closure devices

Endoscopic closure devices

Gastric transmural pressure measurements in vivo: implications for natural orifice transluminal endoscopic surgery (NOTES)

The success of natural orifice surgery depends on a reliable, secure closure of the opening in the gut. Forces that might be exerted on the gastric wall to disrupt closure have not been measured in humans or animals. To determine how transmural gastric pressure gradients vary under different experimental conditions. In vivo porcine model. Animal laboratory. Eleven laboratory pigs. Pressure transducers were placed in the abdomen and stomachs of the test animals. Simultaneous pressure measurements were obtained to determine the stresses applied to the gastric wall during various maneuvers. Continuous intra-abdominal and intragastric pressures in vivo. Transgastric pressure gradients (DeltaP) were computed in real time by subtracting gastric pressure from abdominal pressure. In all cases, the measured gastric pressures were nearly identical to those measured in the abdominal cavity because the stomach is entirely contained within the abdomen. The transmural gastric pressure gradients were near zero during a variety of experimental conditions. Anesthetized animal model, not engaged in usual activities. Relatively low pressures generated during a cough sequence and a Valsalva maneuver compared with reported values in the literature. Estimates of gastric pressures that must be tolerated by gastric closure devices after natural orifice transluminal endoscopic surgery procedures have been greatly overestimated. Absolute gastric pressure is counteracted by external (intra-abdominal) pressure such that the net transmural gastric pressure gradient remains near zero under a variety of conditions.

Bimanual coordination in natural orifice transluminal endoscopic surgery: comparing the conventional dual-channel endoscope, the R-Scope, and a novel direct-drive system

The devices used for natural orifice transluminal endoscopic surgery procedures are endoscopes or inspired by endoscopic design, which makes it difficult to accomplish bimanual coordination. We evaluated 3 operating systems in simulated natural orifice transluminal endoscopic surgery procedures requiring complex bimanual coordination. Operators were required to perform an identical bimanual task by using 3 operating systems: a dual-channel endoscope (DCE); the R-Scope, which has 2 elevators for independent movement of endoscopic instruments; and the Direct Drive Endoscopic System (DDES), which allows separation of instruments and vision, emulating more of a laparoscopic surgery paradigm. A bench-top simulation was used. Twelve teams were recruited for DCE and R-Scope testing. Twelve individuals participated in the DDES setup. The task included 3 steps: picking up a ring, passing it between endoscopic instruments, and placing it on a designated location. Task performance was evaluated by movement speed and accuracy. Task performance was significantly faster when using the DDES system (29 +/- 28 seconds) compared with the other operating systems (DCE: 140 +/- 55 seconds, R-Scope: 160 +/- 71 seconds; P < .001). The difference between the DCE and the R-Scope was not significant (P = .370). Designs that separate vision and motion have more degrees of freedom at the tip of the instruments, and an ergonomic user interface provides benefits for bimanual performance compared with more traditional endoscopic designs. With the DDES, a single operator can perform complex endoscopic tasks faster than 2 operators with a DCE or R-Scope.

Omentoplasty for gastrotomy closure after natural orifice transluminal endoscopic surgery procedures (with video)

The utility of the greater omentum has not been assessed in transluminal access closure after natural orifice transluminal endoscopic surgery (NOTES) procedures. Our purpose was to evaluate the feasibility, efficacy, and safety of omentoplasty for gastrotomy closure. Survival experiments in 9 female 40-kg pigs were randomly assigned to 3 groups: group A, endoscopic full-thickness resection (EFTR) for transgastric access and peritoneoscopy without closure; group B, ETFR and peritoneoscopy with omentoplasty (flap of omentum is pulled into the stomach and attached to the gastric mucosa with clips but no clips are used for gastrotomy closure itself); group C, balloon dilation for opening and peritoneoscopy followed by omentoplasty for closure. The animals were observed for 2 weeks and then underwent endoscopy and necropsy with histologic evaluation. Transgastric opening and peritoneoscopy were achieved in all pigs. In groups B and C, a flap of omentum was easily placed to seal the gastrotomy and then attached to the gastric mucosa with 2 to 5 clips (median 4) in 7 to 20 minutes (median 15 minutes). In group A, peritonitis developed in all animals. In both groups B and C, all animals survived 15 days with no peritonitis and minimal adhesions outside the gastrotomy site. In addition, all achieved complete healing (transmural, n = 4; mucosal ulceration, n = 2) of the gastrotomy site. One animal in group B had an 18-mm abscess in the omental flap. Animal model, small sample size, lack of appropriate controls for group C. Omentoplasty of the gastrotomy site is a technically feasible method to seal balloon-created transgastric access to the peritoneal cavity after NOTES procedures.

Hydrogen leak test is minimally invasive and highly specific for assessment of the integrity of the luminal closure after natural orifice transluminal endoscopic surgery procedures (with video)

Leak-resistant closure of transluminal access is a major challenge facing natural orifice transluminal endoscopic surgery (NOTES). To evaluate a hydrogen (H(2))-based leak test for assessment of transluminal-access closure integrity after NOTES procedures. Nine acute porcine experiments. After gastric-wall puncture and balloon dilation, peritoneoscopy was performed, followed by transmural closure of the gastric opening. The animals were randomly assigned to complete or incomplete closure groups. The H(2) leak test was performed by using 1000 mL of 4% H(2) gas mixture and the Hydrogen Leak Detector H2000+. The animals were then euthanized for a methylene blue (MB) test of gastric closure integrity. Intraperitoneal H(2) concentration after gastric insufflation with H(2). The H(2) leak test was quick and easy. Intraperitoneal H(2) concentrations in parts per million in both groups were similar at baseline (mean +/- SD, 0.18 +/- 0.29 parts per million [ppm] vs 0.22 +/- 0.35 ppm, P = .97) and after balloon dilation (414.8 +/- 198.5 ppm vs 601.3 +/- 116.1 ppm, P > .99). Postclosure intraperitoneal H(2) concentrations dropped to 0.01 +/- 0.77 ppm in the complete-closure group, similar (P = .81) to matched-pairs preopening levels and significantly lower than in the incomplete-closure group (162.0 +/- 83.0 ppm, P < .02). On necropsy, the MB test was negative in all 5 animals of the complete-closure group and positive in all 4 animals of the incomplete-closure group. A cutoff of 25 ppm in intraperitoneal H(2) concentration after closure gave 100% sensitivity, specificity, and positive and negative predictive values for MB leakage. Nonsurvival animal experiments. The H(2) leak test is highly accurate for detection of leakage after NOTES procedures and could become a substitute for currently used MB leak tests.

Closure of a gastrotomy after transgastric tubal ligation by using the Eagle Claw VII: a survival experiment in a porcine model (with video)

Transgastric access to the peritoneal cavity presents new opportunities for novel endoscopic surgery. Secure closure of the gastrotomy site is critical to the success of transgastric endoscopic surgery. To study the safety and efficacy of closure of a gastrotomy by using the Eagle Claw VII endoscopic suturing device after transgastric bilateral tubal ligation. A prospective survival study in a porcine model with ten 30-kg pigs. The gastrotomies were made by using a needle-knife and balloon dilation. Bilateral fallopian tube ligation was performed with detachable snares, and the tubes were transected by using the needle-knife. The gastrotomies were closed with endoscopic suturing by using the Eagle Claw VII. Included the survival of the pigs, security of the closure, number of plicating sutures used, operative time, peritoneal contamination, and histopathologic confirmation of the full-thickness healing of the gastrotomy. Transgastric fallopian-tube ligation was performed in 10 pigs, and all of the gastrotomies were successfully closed by using the Eagle Claw VII endoscopic suturing device. The operative time for bilateral tubal ligation was 38.2 minutes (range 18-50 minutes), whereas, the operative time for gastrotomy closure was 25.5 minutes (range 15-35 minutes). Three endoscopic sutures were necessary to achieve a secure gastrotomy closure. All the pigs survived and tolerated a full diet 24 hours after the operation. A postmortem confirmed full-thickness healing for all gastrotomies, with no evidence of leakage. One pig had an overtube-related esophageal perforation, which was successfully managed with endoscopic clip closure. The porcine gastric wall is thicker than the human gastric wall, and the posterior wall of the porcine stomach becomes the anterior-inferior wall after gaseous distention. Hence, all the gastrotomies were made through the posterior wall. The tissue tolerance and healing of the porcine stomach may be different from that of the human stomach. Endoscopic suturing by using the Eagle Claw VII device is a feasible method for gastrotomy closure after a natural orifice transluminal endoscopic surgery procedure.