Learning colorectal endoscopic submucosal dissection: a prospective learning curve study using a novel ex vivo simulator.

BACKGROUND: Endoscopic submucosal dissection (ESD) is increasingly being used in Asia as a minimally invasive therapy to eradicate large laterally spreading superficial tumors in the colon. To date, the learning curve and effectiveness of ex vivo simulators in colonic ESD training remain unclear. The aim of the study is to determine the learning curve of colonic ESD in an ex vivo simulator. METHODS: We conducted a prospective study of colon ESD in ex vivo porcine colons in a prototype simulator. Three endoscopists with prior experience in gastric ESD but with no experience in colonic ESD each performed 30 ESD resections on standardized lesions in the rectosigmoid and left colon of the porcine simulator. Procedure time, en bloc resection status, and perforation were recorded. RESULTS: All 90 lesions were resected using the ESD technique. The mean time of procedure was 49.6 min (standard deviation 29.6 min). The aggregate rate of perforation was 14.4% and the aggregate rate of non-en bloc resection was 5.6%. Using a composite quality score integrating complications and procedural time, it was found that there was a significant difference between two local polynomial regression lines when using a cut-point at the 9th procedure (p = 0.04), reflecting the point at which most of the learning curve is traversed. CONCLUSIONS: In this study, there were significant improvements realized in colonic ESD performance after 9 colon ESD procedures in ex vivo specimens. Although training will depend on endoscopist skill and expertise, we suggest at least 9 ex vivo procedures prior to moving to live animal or proctored training in colonic ESD.

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

INTRODUCTION AND STUDY AIM: 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). METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Assessment of the length of myotomy in peroral endoscopic pyloromyotomy (G-POEM) using a submucosal tunnel technique (video).

BACKGROUND: Peroral endoscopic pyloromyotomy is a novel technique that has recently been described in the literature. There is little data to guide the length of myotomy created. The aim of study was to evaluate the proper incision length of the muscular layer during peroral endoscopic pyloromyotomy using a submucosal tunnel technique. METHODS: The study was designed as a prospective ex vivo study. Fresh ex vivo porcine stomachs from animals weighing 80-100 kg and porcine stomachs from animals weighing 15-25 kg were used for pyloromyotomy. Four different myotomy lengths (1, 2, 3, and 4) were compared in the large animal series and three different myotomy lengths (1, 2, and 3) were compared in the small series. A total of 23 cases of the submucosal tunnel technique were performed by two endoscopists using 12 large stomachs and 11 small stomachs. RESULTS: The mean overall procedure time (± SD) of pyloromyotomy was 65.7 (± 14.3) min. In the large stomach series, the mean pyloric diameter (± SD) and change from baseline (as percentage) following a 1, 2, 3, and 4 pyloromyotomy were 13.3 ± 9.5 mm (7.1 %), 20.7 ± 11.7 mm (10.6 %), 31.1 ± 15.0 mm (15.2 %), and 33.0 ± 15.0 mm (16.0 %), respectively. In the small stomach series, the changes of mean pyloric diameter following a 1, 2, and 3 cm pyloromyotomy were 12.2 ± 5.6 mm (7.5 %), 23.1 ± 7.6 mm (13.1 %), and 28.0 ± 10.4 mm (15.5 %), respectively. CONCLUSIONS: A 3 cm pyloromyotomy for a large animal series and 2 cm for the small animal series appeared to be most appropriate for enlargement of the pylorus.

Prospective, randomized comparison of a prototype endoscope with deflecting working channels versus a conventional double-channel endoscope for rectal endoscopic submucosal dissection in an established experimental simulation model (with video).

BACKGROUND: A prototype endoscope was designed to improve visualization and dissection of tissue with the use of 2 working channels with different deflections. OBJECTIVE: To evaluate the efficacy and operability of a prototype endoscope in comparison with a conventional double-channel endoscope for rectal endoscopic submucosal dissection (ESD). DESIGN: Randomized, prospective, controlled, ex vivo study. SETTING: Academic medical center. METHODS: A total of 80 standardized artificial lesions measuring 3 × 3 cm were created approximately 5 cm from the anal verge in fresh ex vivo porcine colorectal specimens. Two endoscopists each completed 20 cases with the prototype endoscope and 20 cases with the conventional endoscope. MAIN OUTCOME MEASUREMENTS: An independent observer recorded procedure time, specimen size, en bloc resection, and perforation rate. RESULTS: For the ESD novice, the mean submucosal dissection time (10.5 ± 3.8 vs 14.9 ± 7.3 minutes; P = .024) and total procedure time (18.1 ± 5.2 vs 23.6 ± 8.2 minutes; P = .015) were significantly shorter in the prototype group in comparison with the conventional group. For the ESD expert, there was no significant difference between the mean circumferential resection, submucosal dissection, and total procedure time (prototype group 14.2 ± 6.0 minutes, conventional group 14.2 ± 8.8 minutes; P = .992). The overall perforation and en bloc resection rates were not significantly different between groups. LIMITATIONS: Ex vivo study. CONCLUSION: In this ex vivo prospective comparison study, there was a technical advantage for the ESD novice with the prototype endoscope that resulted in a shorter procedure time, which was not observed for cases performed by the ESD expert.

The learning curve for endoscopic submucosal dissection in an established experimental setting.

INTRODUCTION: Endoscopic submucosal dissection (ESD) has become a standard therapy for early gastric neoplasia, particularly in Asian countries. From a safety and efficacy standpoint, simulation training may empower the endoscopist to be able to learn the basic tenets of ESD in a safe, controlled and supervised setting before attempting first in humans. METHODS AND PROCEDURES: This study was designed as a prospective ex vivo study. Ex vivo porcine organs were utilized in the EASIE-R endoscopic simulator. A total of 150 artificial lesions, each 2 × 2 cm in size, were created in fresh ex vivo porcine stomachs at six different anatomical sites (fundus anterior and posterior, body anterior and posterior, antrum anterior and posterior). Three examiners (2 beginners, 1 expert) participated in this study. All parameters (procedure time, specimen size, en-bloc resection status, perforation) were recorded by an independent observer for each procedure. RESULTS: All 150 lesions were successfully resected using the ESD technique by the three endoscopists. After 30 ESD cases, the two novices performed ESD with a 100% en-bloc resection rate and without perforation. For the procedures performed by the novices, the total procedure time and perforation rate in the last 30 cases were significantly lower than during the first 30 cases (p < 0.05). CONCLUSIONS: Our study suggests that performing 30 ESD resections in an ex vivo simulator leads to a significant improvement in safety and efficiency of performing the ESD technique.

Needs analysis for developing a virtual-reality NOTES simulator.

UNLABELLED: INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emerging surgical technique that requires a cautious adoption approach to ensure patient safety. High-fidelity virtual-reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing the virtual transluminal endoscopic surgery trainer (VTEST) for this purpose. The objective of this study is to conduct a structured needs analysis to identify the design parameters for such a virtual-reality-based simulator for NOTES. METHODS: A 30-point questionnaire was distributed at the 2011 National Orifice Surgery Consortium for Assessment and Research meeting to obtain responses from experts. Ordinal logistic regression and the Wilcoxon rank-sum test were used for analysis. RESULTS: A total of 22 NOTES experts participated in the study. Cholecystectomy (CE, 68 %) followed by appendectomy (AE, 63 %) (CE vs AE, p = 0.0521) was selected as the first choice for simulation. Flexible (FL, 47 %) and hybrid (HY, 47 %) approaches were equally favorable compared with rigid (RI, 6 %) with p < 0.001 for both FL versus RI and HY versus RI. The transvaginal approach was preferred 3 to 1 to the transgastric. Most participants preferred two-channel (2C) scopes (65 %) compared with single (1C) or three (3C) or more channels with p < 0.001 for both 2C versus 1C and 2C versus 3C. The importance of force feedback and the utility of a virtual NOTES simulator in training and testing new tools for NOTES were rated very high by the participants. CONCLUSION: Our study reinforces the importance of developing a virtual NOTES simulator and clearly presents expert preferences. The results of this analysis will direct our initial development of the VTEST platform.

Objective performance measures using motion sensors on an endoscopic tool for evaluating skills in natural orifice translumenal endoscopic surgery (NOTES).

Natural orifice translumenal endoscopic surgery is an emerging procedure. High fidelity virtual reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing a Virtual Transluminal Endoscopic Surgery Trainer (VTEST TM) for this purpose. In this work, objective performance measures derived from motion tracking sensors attached to an endoscope was tested for the transgastric NOTES appendectomy procedure performed with ex-vivo pig organs using the EASIE-R(TM) trainer box. Results from our study shows that both completion time and economy of motion parameters were able to differentiate between expert and novice NOTES surgeons with p value of 0.039 and 0.02 respectively. Jerk computed on sensor 2 data also showed significant results (p = 0.02). We plan to incorporate these objective performance measures in VTEST(TM).

Prospective, randomized comparison of 3 different hemoclips for the treatment of acute upper GI hemorrhage in an established experimental setting.

BACKGROUND: Recently, endoscopic clip application devices have undergone redesign and improvements to optimize their clinical use and effectiveness. Initially designed for the treatment of bleeding nonvariceal lesions, these devices are also increasingly used for the closure of perforations, fistulas, and anastomotic leaks. Several clinical studies, both randomized and nonrandomized, have used endoscopic hemoclips for hemostasis. However, no comparative studies have yet been reported in the literature comparing the latest endoscopic clip devices for usability and effectiveness for hemostasis of acute upper GI hemorrhage. OBJECTIVE: We aimed to compare the usability and efficacy of 3 different types of endoscopic clip application devices in an established experimental setting by using a porcine ex-vivo simulator of upper GI hemorrhage. DESIGN: Randomized, controlled, ex-vivo study. SETTING: Academic medical center. METHODS: Spurting vessels were created within ex-vivo porcine stomachs as published in prior studies. The vessels were attached to a pressure transducer to record the pressure of the circulating blood replacement. Before the initiation of bleeding, each vessel was randomized to 1 of 3 endoscopic clipping devices: 2 different commonly used hemoclips deployed through the working channel and 1 novel clip deployed via an over-the-scope applications device. Two investigators treated 45 bleeding sites (15 bleeding sites for each device at various randomized locations in the stomach: fundus, body, and antrum). MAIN OUTCOME MEASUREMENTS: Usability was measured via the endpoints of procedure time and quantity of clips required to achieve hemostasis. Efficacy was measured via the endpoint of pressure increase (Δp) from baseline to after treatment. RESULTS: All of the 45 hemostasis treatments were carried out successfully. The mean procedure times were significantly different among the hemoclips, with the clip deployed in an over-the-scope fashion requiring significantly less time to attain hemostasis compared with the other 2 clips. For number of clips needed to attain hemostasis, the clip deployed in an over-the-scope fashion was significantly superior to the others. There were also significant differences among the changes in pressure (Δp ± SD) among the different hemoclips tested. LIMITATIONS: Ex-vivo study. CONCLUSIONS: In this prospective, randomized ex-vivo study, we observed significant differences in the usability (time to achieve hemostasis and number of clips required) and the efficacy (change in pressure achieved by the hemoclips) among the 3 clips. The clip applied in the over-the-scope fashion was superior to the other 2 tested clips with regard to time to achieve hemostasis and number of clips required.

Strategies for training in diagnostic upper endoscopy: a prospective, randomized trial.

BACKGROUND: Training simulators have been used for decades with success; however, a standardized educational strategy for diagnostic EGD is still lacking. OBJECTIVE: Development of a training strategy for diagnostic upper endoscopy. STUDY DESIGN: Prospective, randomized trial. SETTINGS: A total of 28 medical and surgical residents without endoscopic experience were enrolled. Basic skills evaluations were performed following a structured program involving theoretical lectures and a hands-on course in diagnostic EGD. Subsequently, stratified randomization to clinical plus simulator training (group 1, n = 10), clinical training only (group 2, n = 9), or simulator training only (group 3, n = 9) was performed. Ten sessions of simulator training were conducted for groups 1 and 3 during the 4-month program. Group 2 underwent standard training in endoscopy without supplemental simulator training. The final evaluation was performed on the simulator and by observation of 3 clinical cases. Skills and procedural times were recorded by blinded and unblinded evaluators. MAIN OUTCOME MEASUREMENTS: Time to reach the duodenum, pylorus, or esophagus. RESULTS: All trainees demonstrated a significant reduction in procedure time during a simple manual skills test (P < .05) and significantly better skills scores (P = .006, P = .042 and P = .017) in the simulator independent of the training strategy. Group 1 showed shorter times to intubate the esophagus (61 ± 26 seconds vs 85 ± 30 seconds and 95 ± 36 seconds) and the pylorus (183 ± 65 seconds vs 207 ± 61 seconds and 247 ± 66 seconds) during the clinical evaluation. Blinded assessment of EGD skills showed significantly better results for group 1 compared with group 3. Blinded and unblinded evaluations were not statistically different. LIMITATIONS: Small sample size. CONCLUSIONS: Structured simulator training supplementing clinical training in upper endoscopy appears to be superior to clinical training alone. Simulator training alone does not seem to be sufficient to improve endoscopic skills.

Hemodynamic efficacy of the over-the-scope clip in an established porcine cadaveric model for spurting bleeding.

BACKGROUND: Clip application has been proven to be effective for endoscopic hemostasis. There are limited bench data on the efficacy of the over-the-scope clip (OTSC) for the treatment of spurting GI hemorrhage. We evaluated the hemodynamic efficacy of the OTSC in an established bleeding model. OBJECTIVE: To evaluate the hemodynamic efficacy of the OTSC in an established bleeding model. DESIGN: Prospective experimental trial with historical comparison. SETTING: We tested the OTSC prospectively in a validated bleeding model by using the compact Erlangen Active Simulator for Interventional Endoscopy equipped with an upper GI organ package. The artificial blood circulation system of the simulator was connected to an arterial pressure transducer. Two investigators with different endoscopic experience (4000 and 10,000 endoscopies performed) participated. Each investigator treated 16 bleeding sites in the simulator with the OTSC by using only suction (n = 8) and a novel retraction device to grasp tissue (n = 8). Systemic pressures were recorded 1 minute before, during, and 1 minute after clip application to objectify the effects of clipping on the vessel diameter. MAIN OUTCOME MEASUREMENTS: Mean and maximum reduction in vessel diameter. RESULTS: The application of the OTSC on the bleeding vessel led to a significant increase in systemic pressure (P < .001) and decreased vessel diameter (P < .001) independent of the endoscopic experience of the investigator. There was no difference in the decrease in vessel diameter based on the application technique (suction vs suction plus grasping). A historical comparison with our former trials demonstrated that the OTSC decreased the vessel diameter significantly more than other traditional endoclips. LIMITATIONS: Small sample size. CONCLUSIONS: We could demonstrate the efficacy of the OTSC with increased hemodynamic efficiency compared with other endoscopic clip devices tested previously.

Efficacy of full-thickness GI perforation closure with a novel over-the-scope clip application device: an animal study.

BACKGROUND: A novel, over-the-scope clip (OTSC) system may be suitable for closure of various GI perforations. The strength and maximum diameter of closure for a single OTSC, however, are unknown. OBJECTIVE: To determine the maximum closure capacity (diameter) and pressure threshold for a single OTSC. DESIGN: Prospective ex-vivo study. SETTING: Academic medical center. METHOD: Full-thickness, standardized defects of 5 mm, 10 mm, 15 mm, 20 mm, and 25 mm were created in porcine stomachs. Similarly, full-thickness defects of 10 mm, 20 mm, 25 mm, 30 mm, and 35 mm were created in porcine colons. A single OTSC was endoscopically deployed 5 times for each full-thickness defect size in an ex-vivo endoscopic simulator. MAIN OUTCOME MEASUREMENTS: Each closure site was tested under water with compressed air for burst pressure. RESULTS: We achieved successful closure in all stomach defects ranging from 5 to 20 mm by using 12-mm OTSCs with short teeth and colon defects ranging from 10 to 30 mm with 14-mm OTSCs with short teeth. Mean (± standard deviation [SD]) burst pressures for the gastric closure sites were 74.9 ± 17.5 mm Hg for 15-mm defects, 49.3 ± 21.6 mm Hg for 20-mm defects, and 15.2 ± 4.1 mm Hg for 25-mm defects. Mean (± SD) burst pressures for the colon closure sites were 117.9 ± 40.1 mm Hg for 20-mm defects, 57.4 ± 4.2 mm Hg for 30-mm defects, and 10.9 ± 7.6 mm Hg for 35-mm defects. LIMITATIONS: Ex-vivo study, does not reflect difficult locations. CONCLUSION: Full-thickness tissue defects ranging from 5 to 20 mm in the stomach and from 10 to 30 mm in the colon can be closed adequately with a single OTSC in an ex-vivo experimental setting. Tissue defects larger than 20 mm in the stomach and 30 mm in the colon may require more than one OTSC or supplemental endoclips to achieve adequate closure. Endoscopic inspection of the closure site does not assure adequate closure of larger perforations.

Development of a pancreatic tumor animal model and evaluation of NOTES tumor enucleation.

BACKGROUND: Laparoscopic distal pancreatectomy is associated with high morbidity and mortality. NOTES tumor enucleation may provide an alternative to laparoscopic distal pancreatectomy. The goal of this study was to determine the feasibility of NOTES tumor creation and enucleation as a multidisciplinary approach. METHODS: A linear-array endoscopic ultrasound (EUS) endoscope was used to inject a thermosensitive ABA triblock polymer mixed with methylene blue through the stomach wall and into the distal pancreas using a 22-gauge EUS needle. Due to its thermosensitive character, the polymer solidifies in response to body temperature, creating an artificial tumor. Seventeen swine underwent NOTES transgastric pancreatic tumor enucleation. Nine nonsurvival animals were sacrificed immediately after the NOTES procedure, with subsequent necropsy. Eight survival animals were observed for up to 16 days after the procedure, subsequently sacrificed, followed by necropsy. RESULTS: The procedure was performed successfully in all 17 pigs studied, 9/9 nonsurvival (100%) and 8/8 survival (100%) animals, using a pure NOTES approach without any laparoscopic ports. Complications included two esophageal dissections (1 in nonsurvival group, 1 in survival group) caused by the introduction of the endoscopic overtube (2/17, 12%), unrelated to the actual surgical procedure. In the survival animals, there were two small splenic lacerations caused during retraction with the endoscopic forceps, for which hemostasis was achieved prior to closure of the gastrotomy (2/7, 29%). At necropsy of the animals, there was sufficient closure of 15/17 gastrotomy sites (88%). CONCLUSIONS: The creation of artificial pancreatic tumors via EUS guidance is feasible. Pancreatic tumor enucleation using a transgastric NOTES approach is technically feasible and could be an alternative to laparoscopic distal pancreatectomy with further development. Further adoption and adaptation of this technique will require the development of more sophisticated specialized tools to improve the safety profile of the procedure.

Influence of storage on larval length and age determination of the forensically important blow fly Lucilia sericata (Diptera: Calliphoridae).

One of the main tasks in forensic entomology is the determination of the minimum post-mortem interval (PMImin) based on the age of the juvenile insects feeding and developing on the dead body. An important task is to store the evidence appropriately so that the evaluation and expert report can be used in court. However, existing recommendations can be contradictory or lacking scientific validation, e.g. by proposing various preservation liquids without knowing whether and to what extent the period of storage in such a liquid has an effect on the length of the preserved larvae. Storage time can be an issue since, due to technical and procedural circumstances, killed larvae may be stored for hours, days, weeks or even longer prior length measurement. A changed body length would have consequences for the entomological report, as the age of the larvae is usually derived from their length. This study investigates the effect of four differently concentrated ethanol solutions (70%, 80%, 90% and 96%) during a storage period of up to 196 days on the body length of stored larvae of the forensically important blow fly species L. sericata (Diptera: Calliphoridae). Larvae of different ages (24 h, 48 h and 72 h after hatching) were killed by immersion in hot, non-boiling water (≥80 °C) for at least 30 s. Their lengths were measured immediately. Subsequently samples were stored in ethanol of appropriate concentration at room temperature (approx. 22 °C). Further length measurements were made at 16 different storage intervals between 1 and 196 days. Many specimens showed a length decrease for most storage conditions and all larval ages. However, there was a tendency for 48 h- and 72 h-old larvae to increase in length after the first days of storage of up to 1.1 mm which may lead to an erroneous overestimation of the PMImin using this kind of specimens. All changes in length within each cohort over total time were in the range of +7% to -9.1%. Significant differences in length changes within the first days of storage were found mainly in larvae stored in 70%- and 80%-ethanol, but larvae stored in 90%- and 96%-ethanol showed first significant differences on day 56 at the earliest. Our results lead to the recommendation that the measurements of fly larvae samples should be taken immediately after killing and before storage to avoid any effects. Ethanol ≥90% should be used for storage.

Efficacy of a prototype endoscope with two deflecting working channels for endoscopic submucosal dissection: a prospective, comparative, ex vivo study.

BACKGROUND: Optimizing the visualization of the cutting line of the submucosal layer is essential to performing an effective and safe endoscopic submucosal dissection (ESD). OBJECTIVE: To evaluate the prototype R-scope compared with a conventional, double-channel endoscope in time required for ESD of mucosal lesions in distinct anatomical locations of the stomach. DESIGN: A prospective, comparative, ex vivo study. INTERVENTION: ESD. MAIN OUTCOME MEASUREMENTS: Procedure time (primary end point measure), specimen size, submucosal injection frequency, en bloc resection rate, and perforation rate (secondary end point measures). RESULTS: In the subgroup of resections in the greater and lesser curvature, the mean (+/- SD) procedure time was significantly less in the R-scope group compared with the conventional endoscope group (8.4 +/- 2.1 minutes vs 11.3 +/- 2.1 minutes, respectively; P = .006), and the mean (+/- SD) submucosal injection frequency was significantly less in the R-scope group compared with the conventional endoscope group (1.9 +/- 0.6 vs 2.5 +/- 0.5, respectively; P = .025). There were no significant differences in procedure time, specimen size, submucosal injection requirements, en bloc resection rate, and perforation rate between the two endoscopic groups of all combined anatomic lesions. LIMITATIONS: Small, ex vivo study. CONCLUSION: ESD by using the R-scope may provide an improved platform for quicker ESD, especially in greater and lesser curvature anatomical lesions of the stomach.

Triluminal hybrid NOS as a novel approach for colonic resection with colorectal anastomosis.

BACKGROUND: Minimal invasive surgery has led to a significant decrease in surgical trauma, pain, recovery time and improved cosmesis compared with open surgery. However, scar development and the risk of hot spots for infections and hernias are still present. Natural orifice surgery (NOS) promises to offer even further reduction in invasiveness and thus may lead to even faster recovery. The goal of this study was to establish a NOS colonic resection by using commercially available standard surgical instruments avoiding major abdominal incisions. METHODS AND RESULTS: This article reports a new triluminal hybrid NOS approach for sigmoid and colonic resection (Tri-Port-NOS-SIG), established using rigid laparoscopic instruments through the umbilicus, the vagina, and the rectum, without any major abdominal incision. The specimen was retrieved through the anus avoiding dilatation of the vagina. In an early series of 5 patients the first patient was a 37-year-old woman with a 10-year history of recurrent diverticulitis. She recovered quickly and was discharged on postoperative day 2. She returned to sports activity on day 12 postoperatively and to her heavy-duty job on day 16. The following 4 patients also recovered well and were discharged on postoperative days 7 (2 patients), 8, and 11, respectively. One patient experienced a temporary, mild paresthesia of the left lower dorsal leg, most likely because of intraoperative positioning. No major complications occurred. CONCLUSION: Tri-Port-NOS-SIG offers a feasible scarless approach for abdominal resections using commercially available surgical instruments in experienced hands.

Trilumenal hybrid-NOS proctocolectomy.

BACKGROUND: The authors hypothesized that by combining transumbilical, transvaginal, and transrectal accesses, complex bowel operations, including proctocolectomy with restorative J pouch [corrected] reconstruction, might be possible. METHODS AND RESULTS: Out of a series of 30 natural orifice surgery (NOS) operations performed at the authors' institution in the past 12 months, proctocolectomy with ileoanal pouch reconstruction was planned for 3 female patients (31 years, BMI = 30; 50 years, BMI = 31; 30 years, BMI = 21) with extensive disease of ulcerative colitis, and they were operated via a 3-lumenal NOS approach. The first 2 patients received a proctocolectomy with a J-pouch formation. A 3-stage procedure was planned for the third patient, and she received a total colectomy. The colonic specimen was retrieved through the anus obviating dilation of the vagina. The J-pouch was prepared through a horizontal 2-cm incision, which later served as the protective loop ileostomy site. CONCLUSION: Trilumenal NOS proctocolectomy is feasible and safe providing a solution to overcome the lack of triangulation using a single-lumen approach.

The complementary Erlangen active simulator for interventional endoscopy training is superior to solely clinical education in endoscopic hemostasis--the French training project: a prospective trial.

BACKGROUND: The Erlangen Active Simulator for Interventional Endoscopy (EASIE) using ex-vivo porcine organs was introduced in 1997. The present study should analyze whether repeated EASIE simulator training in endoscopic hemostasis led to superior performance compared with a traditionally educated group. The results were compared with a similar project in New York. METHODS: Thirty-five French GI fellows were enrolled. Baseline skills evaluation was performed in four disciplines (manual skills, injection/coagulation, clip application and variceal ligation) using the compactEASIE-simulator equipped with an upper gastrointestinal organ package for bleeding simulation. The same, translated evaluation forms (from the prior New York project) were used. Subsequently, fellows were randomized into group A (n=17, only clinical education) and group B (n=18, additional three simulator trainings). Group B was trained the next day and after 4 and 7 months by experts of the French Society of Gastrointestinal Endoscopy. Both groups performed routine and emergency endoscopies at their home hospitals during the study period. Both groups were re-evaluated blindly after 9 months. RESULTS: The learning curve for group B showed a significant improvement in all disciplines (P<0.004) whereas group A improved significantly in only two of four disciplines at blinded final evaluation (manual skills P=0.02, injection/coagulation P=0.013). The direct comparison of groups B and A at blinded final evaluation showed significantly superior ratings for group B in all disciplines (P<0.006) and significantly shorter performance times in two disciplines (P=0.016 each). The comparison with the similar 'New York project' revealed that preexisting differences in skills were adjusted by the training. CONCLUSION: Complementary trainings (three workshops in 7 months) in endoscopic hemostasis using the compactEASIE improved skills compared with a solely clinical education. The results of the 'New York project' were confirmed and benefits were independent from the medical educational system.

Simulator training in endoscopic hemostasis.

Simulation of upper gastrointestinal (GI) hemorrhage provides the opportunity to practice endoscopic hemostasis without the risk of patient harm and time limitations. Various models have been developed to simulate an acute bleeding source in the upper GI tract to evaluate the feasibility of new endoscopic devices or to practice interventional techniques in a calm and controlled environment. Increasingly available ex vivo models provide this opportunity without the ethical concerns involved with live-animal courses. Validation studies have proven acceptance of ex vivo models and improved clinical performance by repetitive training using these models.

Prospective, Randomized Ex Vivo Trial to Assess the Ideal Stapling Site for Endoscopic Fundoplication with Medigus Ultrasonic Surgical Endostapler.

Background and Aims. Endoscopic fundoplication is an emerging technique for the treatment of gastroesophageal reflux disease (GERD). The aim of this study is to determine the ideal position of the staples in relation to gastroesophageal junction (GEJ). Methods. Ten endoscopic fundoplication procedures were performed in each group using fresh ex vivo porcine stomachs: Group A: 2 staples each at 3 cm above the GEJ and 180° apart; Group B: 2 staples at 3 cm and 90° apart; Group C: 2 staples at 4 cm and 180° apart; Group D: 3 staples at 3 cm with 90° between each staple (180° total). After the procedure, the stomach was gradually filled with water. Gastric yield pressure (GYP) was determined by detection of reflux of the water in esophagus or by rupture of staples. Results. Mean increase of GYPs (±SD) after the procedure was as follows: Group A: 16.9 ± 8.7; Group B: 8.1 ± 7.9; Group C: 12.2 ± 9.4; Group D: 22.7 ± 13.3. GYP in Group A and Group D was higher than Group B (p = 0.03 and p = 0.01, resp.). Conclusions. We recommend the placement of 3 staples at 3 cm distance from the GEJ, which resulted in the highest increase of GYP.

Pre-clinical Training for New Notes Procedures: From Ex-vivo Models to Virtual Reality Simulators.

Natural orifice transluminal endoscopic surgery (NOTES) is a newer field of endoscopic surgery that allows for scarless treatment of pathologic entities, using novel transluminal approaches. There has been a shift of focus from a clinical and research standpoint from the development and dissemination of "first-generation" NOTES procedures to "new NOTES" procedures that traverse the mucosa of luminal structures, yet do not stray far into the peritoneal cavity. It has been a challenge to find appropriate and effective ways to train gastroenterologists and surgeons in these novel approaches. We review the importance of simulation in training and discuss available simulation options.