Transgastric surgery in the abdomen: the dawn of a new era?

Acute appendicitis and its treatment: a historical overview

PURPOSE

Acute appendicitis (AA) is the leading cause of acute abdomen worldwide, with an incidence of 90-100 cases per 100,000 individuals annually and a lifetime risk of 7-12%. Despite its prevalence, historical accounts of AA are limited, particularly when compared to conditions like haemorrhoids, likely due to the appendix's internal location. This article traces the historical evolution of AA treatment from ancient times to the present, highlighting key contributions.

METHODS

A review of common research databases and relevant literature on AA was conducted.

RESULTS

Evidence from ancient Egypt suggests early recognition of the appendix, referring to it as the "worm of the bowel." However, detailed anatomical descriptions and treatment approaches for AA did not emerge until the Renaissance, particularly with contributions from Leonardo da Vinci and Berengario da Carpi. The article traces the progression of AA management, including the first autopsies and surgeries, the development of surgical techniques predating anaesthesia and antisepsis, and advancements achieved from the nineteenth to the twenty-first century. The shift from conservative to surgical approaches is discussed, alongside innovations such as laparoscopic appendicectomy, single-incision laparoscopic surgery (SILS), natural orifice transluminal endoscopic surgery (NOTES), and endoscopic retrograde appendicitis therapy (ERAT). The impact of the COVID-19 pandemic on AA treatment, including adaptations in medical practices, is also explored.

CONCLUSIONS

This review highlights the significant historical developments in AA treatment and its pivotal role in advancing abdominal surgery.

[NOTES in visceral surgery : Current status]

The idea to use natural orifices as an access route for operations in the body has inspired many clinicians and researchers worldwide. Some of these expected a continuation of the development from open surgery to laparoscopic surgery finally to a less invasive modality. Others hoped for economic benefits for endoscopists to take over previous surgical patients into gastroenterological departments. The first experimental studies demonstrated that the initial expectations could not be implemented in a short period of time. The available endoscopes could not be proved for advanced procedures. Key problems like sterility, infection control, tissue manipulation, safety of access closure, and specimen retrieval manifested to be too large for routine clinical use. However, the attraction of the natural orifice transluminal endoscopic surgery (NOTES) philosophy has resulted in a reduction of the number and diameters of trocars in laparoscopic surgery. Hybrid NOTES as a combination of classical laparoscopic access with natural orifice instrumentations (mostly transvaginal) have become clinical reality in many hospitals. This development fits into the long-term trend towards less invasive surgery and more effective interventional methods in endolumenal endoscopy.

Shifting Paradigms in Minimally Invasive Surgery: Applications of Transanal Natural Orifice Transluminal Endoscopic Surgery in Colorectal Surgery

Since the advent of laparoscopy, minimally invasive techniques such as single port laparoscopy, robotics, endoscopically assisted laparoscopy, and transanal endoscopic surgery continue to revolutionize the field of colorectal surgery. Transanal natural orifice transluminal endoscopic surgery (NOTES) represents a further paradigm shift by combining the advantages of these earlier techniques to reduce the size and number of abdominal incisions and potentially optimize rectal dissection, especially with respect to performance of an oncologically adequate total mesorectal excision (TME) for rectal cancer. Since the first experimental report of transanal rectosigmoid resection in 2007, the potential impact of transanal NOTES in colorectal surgery has been extensively investigated in experimental models and recently transitioned to clinical application. There have been 14 clinical trials of transanal TME (taTME) for rectal cancer that have demonstrated the feasibility and preliminary oncologic safety of this approach in carefully selected patients, with results comparable to outcomes after laparoscopic and open TME, including cumulative intraoperative and postoperative complication rates of 5.5 and 35.5%, respectively, 97.3% rate of complete or near-complete specimens, and 93.6% rate of negative margins. Transanal NOTES has also been safely applied to proctectomy and colectomy for benign indications. The consensus among published series suggests that taTME is most safely performed with transabdominal assistance by surgeons experienced with laparoscopic TME, transanal endoscopic surgery, and sphincter-preserving techniques including intersphincteric resection. Future applications of transanal NOTES may include evolution to a pure endoscopic transanal approach for TME, colectomy, and sentinel lymph node biopsy for rectal cancer, with a potential role for robotic assistance.

Randomized trial on the physiologic impact of NOTES

BACKGROUND

Our previous work revealed significantly less acidosis in swine undergoing natural orifice translumenal endoscopic surgery (NOTES) using endoscopic air insufflation than swine undergoing standard laparoscopy. We wanted to evaluate the differential effects of CO2 versus intra-abdominal pressure as source for this finding. In addition, we investigated the endocrine stress response between swine undergoing NOTES peritoneoscopy with CO2 insufflation and animals undergoing standard diagnostic laparoscopy with CO2.

MATERIALS AND METHODS

Twenty-eight (28) female 50-kg domestic pigs were randomly assigned to one of four groups using a permuted block randomization table: Group 1: NOTES using CO2 insufflation, Group 2: NOTES using air insufflation, Group 3: laparoscopy max pressure 12 mmHg and Group 4: laparoscopy with max pressure 7 mmHg. Invasive monitoring lines were placed. Pneumoperitoneum was established by the respective method and maintained for 90 min, visualizing liver, spleen and colon. Arterial blood gas was obtained at baseline and four additional time points. Serum TNF-α for POD (postoperative day) 1 and cumulative urine adrenaline for the procedure were determined by ELISA. ANOVA and t test were used for statistical comparison. The study was Institutional Animal Care and Use Committees approved.

RESULTS

All experiments were completed as outlined. Blood pH showed a significant difference between groups. Serum TNF-α revealed higher levels for NOTES CO2 on POD 1 than standard laparoscopy (p = 0.03).

CONCLUSION

NOTES animals with CO2 insufflation initially experienced similar pH compared to standard laparoscopy but recovered to levels seen in low-pressure laparoscopy and NOTES with air. NOTES with CO2 appears to elicit a stronger stress response in this study than standard or low-pressure laparoscopy or NOTES with air.

Minimal invasive surgery: NOSE and NOTES in ulcerative colitis

BACKGROUND

In patients with ulcerative colitis (UC), laparoscopic pelvic dissection for IPAA is not always straightforward: often, a hand-assistance incision is used to complete the proctectomy, lengthening operative times. Hybrid NOSE and NOTES are emerging as an alternative approach to conventional laparoscopy. We believe that UC patients could benefit from this new hybrid approach in three ways: by easing the proctectomy as performed down to up, avoiding additional incisions and decreasing surgical times. We present the short-term outcomes of our series.

METHODS

All patients with UC who required IPAA were enrolled in a single-arm prospective study (July 2011 to March 2014). A three-step procedure was performed. The first step: laparoscopic colectomy (with transanal removal of the colon) and temporary ileostomy. The second step: "down-to-up" proctectomy (with transanal removal of the rectum) and IPAA with a covering ileostomy. We combined simultaneously transanal and laparoscopic approach. The third step: ileostomy closure. Functional outcomes were assessed 3 months after third step.

RESULTS

Eighteen patients were enrolled. Two patients are waiting to complete the second stage, and 16 underwent all surgical steps. Twelve have been evaluated with functional scores. For the first step, the mean operative time was 162.2 min (SD 40.5) and 170 min (SD 50.1) for the second one. The median hospital stay was 6 days (IQR 5-14.75) for the first step and 5.5 (IQR 5-9.75) for the second one. No major complications occurred. Twenty-four-hour defecation frequency was 5.5 per day (SD 1.7), 0.5 per night. Seventy-five percentage of patients may retain stools for more than 30 min; the mean value of Oresland score was 4.7 and Wexner score 1.4.

CONCLUSIONS

This is a safe and feasible technique to treat UC patients with good short-term outcomes. Long-term outcomes and controlled trials are needed.

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.

Sashimi NOTES--extraction of bulky specimens in no-scar operations

A major obstacle in no-scar surgery is the extraction of large, bulky or rigid specimen. Thus, a method is needed that allows for extraction of large specimens without situs contamination in women and men. It should enable safe treatment of infectious or malignant disease while preserving pathologic workup. Five patients suffering from diverticulitis with expected bulky and rigid specimen were enrolled into this early series. Preparation was performed transumbilically in single-port technique. To prevent new scar formation, the incision was limited to the base of the umbilicus without extension onto the sound abdominal skin. A functionally and topologically extracorporeal compartment was created within the abdomen by introduction and insufflation of a tear-proof impermeable retrieval bag. The specimen was sliced in a controlled fashion inside the compartment along a pre-marked geometry. Controlled specimen dissection in a dedicated intraabdominal resection compartment was feasible. The dissected specimen could be retrieved through the 1.5 cm umbilical incision without spillage of material. The geometry of the extracted organ was reconstructed in detail allowing for uncompromised pathological workup. Extraction of bulky and rigid specimen is possible through natural orifices by the proposed controlled dissection method enabling the pathologist to reconstruct anatomical affiliation.

Transgastric endoscopic fenestration of a hepatic cyst: a report of one case

We present a case of transgastric endoscopic fenestration of a symptomatic simple hepatic cyst in the left lobe. After per-oral intubation, the anterior wall of the stomach was punctured with a needle. After the anatomic location was defined by intraperitoneal endoscopic ultrasound, fenestration was performed by gastric endoscopy. The procedure was successfully performed without any difficulties. The patient had an uncomplicated postoperative course. This method is technically feasible and represents a potential new approach to the treatment of simple hepatic cysts.

Initial experience from the transgastric endoscopic peritoneoscopy and biopsy: a stepwise approach from the laboratory to clinical application

BACKGROUND AND AIM

Natural-orifice translumenal endoscopic surgery (NOTES) is a newly minimally invasive technique that gives access to the abdominal cavity via transgastric, transcolonic, transvaginal or transvesical routes. The aim of the present study was to evaluate the safety and feasibility of transgastric endoscopic peritoneoscopy and biopsy from laboratory to clinical application.

METHODS

With the animals under general anesthesia, a sterile esophageal overtube was placed and a gastric antibiotic lavage was performed. Subsequently, a needle-knife and through-the-scope dilating balloon were used to make an anterior gastric wall incision through which a therapeutic gastroscope was advanced into the peritoneal cavity. After 2 weeks, another transgastric endoscopic exploration was performed in a different location of the stomach. The peritoneal cavity was examined before the gastric incision was closed. After 4 weeks of observation, necropsy was performed. In the clinical application, after gastric lavage, the first step was the creation of the gastrotomy under general anesthesia, sometime under direct vision of the laparoscopic scope. Then the endoscope can be maneuvered in the peritoneal cavity. And peritoneoscopy and biopsy were performed. Biopsies can be obtained from any suspicious areas using punch biopsy forceps. The gastrotomy was then closed with clips. The gastroscopy was examined after one week.

RESULTS

Twenty-eight transgastric endoscopic peritoneoscopies and biopsies in pigs and a total of five transgastric human endoscopic peritoneoscopies and biopsies have been performed. All procedures were completed satisfactorily in the pig model and all patients. There were no intraoperative or postoperative complications.

CONCLUSIONS

The advantages of peritoneoscopy and biopsy appeared to be enhanced by this approach. Patients had minor postoperative pain and minimal scarring. It is safe and feasible for us to use transgastric endoscopic peritoneoscopy and biopsy in humans.

Technical skill set training in natural orifice transluminal endoscopic surgery: how should we approach it?

BACKGROUND

The boundaries in minimally invasive techniques are continually being pushed further. Recent years have brought new and exciting changes with the advent of natural orifice transluminal endoscopic surgery. With the evolution of this field of surgery come challenges in the development of new instruments and the actual steps of the procedure. Included in these challenges is the idea of developing a proficiency-based curriculum for training.

METHODS

A review of the currently available literature was performed to support the points discussed.

RESULTS

In this article we address and discuss the issues of who, when, where, and how to teach suitable trainees in the technique of natural orifice transluminal endoscopic surgery.

CONCLUSION

What comes to the fore is the importance of providing safe and structured training in these techniques.

Multimedia article. Natural orifice transluminal endoscopic surgery applied to sigmoidectomy in survival animal models: using paired magnetic intra-luminal device

BACKGROUND

The clinical application of natural orifice transluminal endoscopic surgery (NOTES) for sigmoidectomy is associated with several difficulties that need to be overcome before wider clinical application of the procedure. The purpose of this study was to evaluate the technical feasibility and safety of transgastric sigmoidectomy in a survival animal model, as well as to evaluate the safety and usability of a custom paired magnetic intraluminal device, which we developed for the NOTES procedure.

METHODS

Survival experiments were conducted on 24-33-kg dogs. After anesthesia, a gastrotomy was created using double-channel endoscope, and peritoneoscopy was performed. The sigmoid colon was retracted laterally using paired magnetic intraluminal device, the mesocolon was dissected, and the branch vessel was sealed. The anvil was placed into the descending colon through anus. A proximal and distal colonic transection was then performed. The circular stapler was passed through the anus and performed end-to-end anastomosis. Afterwards the specimen was removed through gastrotomy, and the gastric incision was closed. Postoperatively, all dogs were recovered and monitored for well-being during convalescence. Reexploration was practiced under anesthesia 2 weeks after surgery for evaluation of intra-abdominal complications, and intra-peritoneal cultures for microorganism.

RESULTS

The mean operative time was 141 (range, 122-157) min. There were no complications or physical evidence of sepsis or bowel obstruction during the observation period. Only one dog exhibited decreased body weight, decreasing to 20.4 kg from 22.4 kg after surgery; all of the other dogs exhibited increased body weight. We observed no evidence of peritonitis, intra-abdominal abscess, bleeding, or organ injury on reexploration conducted on day 14 after surgery.

CONCLUSIONS

Transgastric NOTES sigmoidectomy is a safe operation technique as evaluated in a dog model. The paired magnetic intraluminal device that was used in this study was useful to avoid an abdominal incision for retracting the sigmoid colon.

International multicenter trial on clinical natural orifice surgery--NOTES IMTN study: preliminary results of 362 patients

OBJECTIVES

Natural orifice translumenal endoscopic surgery (NOTES) is evolving as a promising alternative for abdominal surgery. IMTN Registry was designed to prospectively document early results of natural orifice surgery among a large group of clinical cases.

METHODS

Sixteen centers from 9 countries were approved to participate in the study, based on study protocol requirements and local institutional review board approval. Transgastric and transvaginal endoscopic natural orifice surgery was clinically applied in 362 patients. Intraoperative and postoperative parameters were prospectively documented.

RESULTS

Mean operative time for transvaginal cholecystectomy was 96 minutes, compared with 111 minute for transgastric cholecystectomy. A general complication rate of 8.84% was recorded (grade I-II representing 5.8%, grade III-IV representing 3.04%). No requirement for any analgesia was found in one fourth of cholecystectomy and appendectomy patients.

CONCLUSIONS

Results of clinical applications of NOTES in the IMTN Study showed the feasibility of different methods of this new minimally invasive alternative for laparoscopic and open surgery.

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.

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

BACKGROUND

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

OBJECTIVE

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

DESIGN AND INTERVENTION

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

MAIN OUTCOME MEASUREMENTS

Histological healing of the gastric wall opening.

RESULTS

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

LIMITATIONS

Animal model with short-term follow-up.

CONCLUSIONS

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

The role of single-incision laparoscopic surgery in abdominal and pelvic surgery: a systematic review

OBJECTIVE

This review aimed to determine the role of single-incision laparoscopic surgery (SILS) in abdominal and pelvic operations.

DATA SOURCES

The Medline, EMBASE, and PsycINFO databases were systematically searched until October 2009 using "single-incision laparoscopic surgery" and related terms as keywords. References from retrieved articles were reviewed to broaden the search

STUDY SELECTION

The study included case reports, case series, and empirical studies that reported SILS in abdominal and pelvic operations.

DATA EXTRACTION

Number of patients, type of instruments, operative time, blood loss, conversion rate, length of hospital stay, length of follow-up evaluation, and complications were extracted from the reviewed items

DATA SYNTHESIS

The review included 102 studies classified as level 4 evidence. Most of these studies investigated SILS in cholecystectomy (n=34), appendectomy (n=24), and nephrectomy (n=17). For these procedures, operative time, hospital stay, and complications were comparable with those of conventional laparoscopy. Conversion to conventional laparoscopy was seldom performed in cholecystectomy (range, 0-24%) and more frequent in appendectomy (range, 0-41%) and nephrectomy (range, 0-33%).

CONCLUSION

The potential benefits of SILS include superior cosmesis and possibly shorter operative time, lower costs, and a shortened time to full physical recovery. Careful case selection and a low threshold of conversion to conventional laparoscopic surgery are essential. Multicenter, randomized, prospective studies are needed to compare short- and long-term outcome measures against those of conventional laparoscopic surgery.

Impact of body image on patients' attitude towards conventional, minimal invasive, and natural orifice surgery

PURPOSE

A series of investigations proposed that patients' preference on minimal invasive and scarless surgery may be influenced by age, sex, and surgical as well as endoscopic history of the individual patient. However, it is unknown which psychological criteria lead to the acceptance of increased personal surgical risk or increased personal expenses in patients demanding scarless operations. We investigated whether individual body image contributes to the patient's readiness to assume higher risk in favor of potentially increased cosmesis.

MATERIALS AND METHODS

We conducted a nonrandomized survey among 63 consecutive surgical patients after receiving surgery. Individual body image perception was assessed postoperatively applying the FKB-20 questionnaire extended by four additional items. The FKB-20 questionnaire is a validated tool for measuring body image disturbances resulting in a two-dimensional score with negative body image (NBI) and vital body dynamics (VBD) being the two resulting scores. A subgroup analysis was performed according to the conducted operations: conventional open surgery = group 1, traditional laparoscopic surgery = group 2, and no scar surgery = group 3.

RESULTS

There was a significant correlation between a negative body image and the preference for scar sparing and scarless surgery indicated by a significantly increased acceptance of surgical risks and the willingness to spend additional money for receiving scarless surgery (r = 0.333; p = 0.0227). Allocated to operation subgroups, 17 of 63 patients belonged to group 1 (OS), 29 to group 2 (minimally invasive surgery), and 17 patients to group 3 (no scar). Although age and sex were unequally distributed, the groups were homogenous regarding body mass index and body image (NBI). Subgroup analysis revealed that postoperative desire for scar sparing approaches was most frequently expressed by patients who received no scar operations.

CONCLUSIONS

Patients with an NBI tend towards scarless surgery and are willing to accept increased operative risk and to spend additional money for improved postoperative cosmesis.

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.

Early experience in human hybrid transgastric and transvaginal endoscopic cholecystectomy

BACKGROUND

Abdominal procedures have been performed for a long time through the anterior abdominal wall. Since the first reports in the 1980s, laparoscopy has become the standard for cholecystectomy, with many advantages over open procedures. Now a natural-orifice approach to the peritoneal cavity may further reduce the invasiveness of surgery by either diminishing or avoiding abdominal incisions. Several orifice routes to the abdominal cavity have been described: transgastric, transvaginal, transvesical, and transcolonic. Although most experiences with the porcine model showed the possibility of these approaches, few surgeons reported experiences with humans. The authors present their complete early experience with transgastric (TG) and transvaginal (TV) cholecystectomies in human beings.

METHODS

Thirty-nine patients (4 males and 35 females) underwent hybrid NOTES procedures from January 2007 to January 2009. The mean age was 46 years (range = 19-83). The body mass index ranged from 20 to 41 and ASA was I-II. Transgastric (TG) cholecystectomy was performed in 27 patients and 12 patients had a transvaginal (TV) cholecystectomy.

RESULTS

The mean operative time was 140 min. Although operative times were slightly shorter in the TG group 005B137 +/- 34.6 min (range = 75-195)] compared to the TV route [147 +/- 31.5 min (range = 95-220)], there were no significant differences between the two groups (p = 0.5, Mann-Whitney U test). Patients were started on liquids within 1 h and discharged 2 h later, except the last 11 TG patients, who went home 24 h later because of enrollment in a separate protocol. An overall 20% morbidity rate and no mortality were found. The complication rates for the TG and TV groups were 18% (5/27) and 25% (3/12), respectively, which was not statistically significant (p = 0.6, chi(2) test). Seventy-five percent of complications (6/8) occurred the first year and 25% (2/8) during the second year of our experience.

CONCLUSION

Transgastric and transvaginal cholecystectomies are feasible. Although these NOTES procedures were laparoscopically assisted and current flexible endoscopes were used, it seems possible that major intra-abdominal surgeries may one day be performed without skin incisions. However, a learning curve is mandatory and, although there were no major bile duct injuries, there were NOTES-related complications. These trends toward incisionless surgery demand coordinated research in an interdisciplinary setting involving both surgeons and device manufacturers to further define appropriate indications, contraindications, and applications for natural-orifice surgery.

Natural Orifice Trans-Luminal Endoscopic Surgery in the esophagus

As limited as are the studies regarding peritoneal Natural Orifice Trans-Luminal Endoscopic Surgery, mediastinal transluminal experiments are certainly in their infancy. The authors evaluate the parallel development of minimally invasive thoracic surgery with regard to its counterpart in peritoneal laparoscopy to NOTES. Transesophageal interventions by both endosonographic and direct visualization are examined in the context of minimally invasive surgery and mediastinal NOTES. Techniques of viscerotomy creation, visualization, and closure are examined with particular emphasis on mediastinal structures. The state of current interventions is examined. Finally, current morbidity (including infectious complications) and survival outcomes are examined in those animals that have undergone transesophageal exploration.

[Diagnostic and interventional endoscopy in gastroenterology : from high-resolution chips and procedures for endoscopic resection to NOTES]

In the past 10 years endoscopic diagnostics has benefited from technologies such as big chips, high-definition television (HDTV) and narrow band imaging (NBI). Video capsule endoscopy and double balloon enteroscopy have facilitated visualization of the entire small bowel. A number of studies on mucosal Barrett's and gastric cancers could prove that endoscopic mucosal resection (EMR) is oncologically equivalent to surgical resection when certain criteria are respected. However, EMR is less invasive and carries a substantially lower complication risk and mortality compared to surgery. Endoscopic submucosal dissection (ESD) facilitates en bloc resection with thorough histopathologic evaluation of the specimen, e.g. for mucosal lesions in the stomach and rectum. Endosonography (EUS) guided transgastric necrosectomy using a flexible gastroscope has set a milestone in the treatment of infected pancreatic necroses and has replaced open surgery in many centers. Natural orifice transluminal endoscopic surgery (NOTES) uses natural body openings as minimally invasive access to the abdomen and mediastinum. Interventional GI endoscopists and minimally invasive surgeons have profited from these innovations in micromechanics and microelectronics.

Microbiological contamination during transgastric and transvaginal endoscopic techniques

Natural orifice transluminal endoscopic surgery (NOTES) has gained widespread interest as a potentially alternative to laparoscopic surgery, but concerns over peritoneal contaminations are unsolved. The aim of our study was to assess the safety of transluminal surgery by investigating the intraperitoneal bacterial load and contamination during transgastric and transvaginal surgeries. Twelve female pigs underwent transgastric (n = 7; tubal ligation and oophorectomy) and transvaginal procedures (n = 5; cholecystectomy). All animals were sacrificed after 2 weeks. The procedures were performed by using a double-channel endoscope (GIF-2T160; Olympus, Tokyo, Japan) under general anesthesia. Peritoneal fluid sampling was taken immediately after entry into the abdomen, at the end of the surgical procedure and during the autopsy, and sent for microbiologic assessment. In the transgastric group, 6 animals completed the surgical procedures and survived. Three pigs experienced signs of postoperative peritonitis with abscesses and adhesions visible and Escherichia Coli isolated at autopsy. In the transvaginal group, a cholecystectomy was performed without technical problems in all animals. No signs of postoperative sepsis nor growth in the microbiologic samples were recorded. In conclusion, the transvaginal approach seemed to be safer and produced less intra-abdominal contamination and sepsis, compared to the transgastric approach. Although both transgastric tubal ligation and oophorectomy and transvaginal cholecystectomy were feasible using equipment and accessories currently available for conventional endoscopy, new procedure-specific instruments and equipment should be developed to allow the operator safer access into the peritoneum.

New hybrid approach for NOTES transvaginal cholecystectomy: preliminary clinical experience

OBJECTIVES

Natural orifice translumenal endoscopic surgery (NOTES) represents the first step toward scar-less surgery. The objective of this study is to evaluate early clinical results of transvaginal cholecystectomy using a new technique.

METHODS

Institutional review board approval was obtained and transvaginal NOTES cholecystectomy was performed in 12 women for cholelithiasis. A 2-channel videoendoscope was inserted in the abdominal cavity through a posterior colpotomy. Two 3-mm trocars were inserted deep in the umbilicus, and a 10-mm trocar was placed through the colpotomy parallel to the endoscope. Dissection was performed with endoscopic instruments combined with 3-mm laparoscopic instruments.

RESULTS

Mean operative time was 125.8 minutes. All procedures occurred without intraoperative complications or conversions, except for 1 vulvar laceration. There were no postoperative complications in the clinical follow-up.

CONCLUSION

Transvaginal NOTES is a feasible and safe alternative for cholecystectomy in this preliminary clinical experience, allowing good cosmetic benefits and low analgesic requirement.

Anatomical considerations for natural orifice translumenal endoscopic surgery

Success in surgical procedures relies on the surgeon's understanding of anatomy and the ways in which the internal organs relate to one another. Recently, a new surgical technique has been introduced. Natural orifice translumenal endoscopic surgery (NOTES) uses the body's natural orifices (mouth, anus, urethra, or vagina) as entrance points to the peritoneal cavities (through the stomach, rectum, bladder, or posterior vaginal fornix). NOTES techniques have proven feasible in both animal and early human trials. While it remains to be seen what advantages NOTES possesses over traditional surgical approaches, a clear understanding of human anatomy will be critical for successful, safe NOTES procedures. This article summarizes the development and the basic techniques of NOTES and reviews those anatomical considerations specific to NOTES.

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

INTRODUCTION

The utility of the greater omentum has not been assessed in transluminal access closure after natural orifice transluminal endoscopic surgery (NOTES) procedures.

OBJECTIVE

Our purpose was to evaluate the feasibility, efficacy, and safety of omentoplasty for gastrotomy closure.

METHODS AND PROCEDURES

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.

RESULTS

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.

LIMITATIONS

Animal model, small sample size, lack of appropriate controls for group C.

CONCLUSIONS

Omentoplasty of the gastrotomy site is a technically feasible method to seal balloon-created transgastric access to the peritoneal cavity after NOTES procedures.

Navigation systems and platforms in natural orifice translumenal endoscopic surgery (NOTES)

INTRODUCTION

The latest evolution in minimally invasive surgery is to avoid skin incisions by using natural orifices, called natural orifice translumenal endoscopic surgery (NOTES). However, to safely and efficiently perform NOTES, the requirements of the operating platform used need to be modified from the conventional endoscope. The aim of this paper is to systematically review specialised operating platforms used or in development for NOTES procedures.

METHODS

A review of the literature was conducted using Ovid EMBASE, Ovid MEDLINE, ISI Current Contents Connect and PubMed, a search tool of the National Library of Medicine and the national institute of Health, until the 1st of December 2008. Data was extracted to specifically characterise the available platforms, their availability, advantageous characteristics and potential disadvantages.

RESULTS

There were 9 studies included in this review describing 6 different navigation platforms and 3 robotic systems for NOTES. Based on this analysis, it is our opinion that although the described surgical systems and navigation platforms possess some attractive characteristics, such as maneuverability, stability, enhanced optics, and the ability to provide triangulation and insufflation with proper suction/irrigation maintenance, there does not appear to be one platform which is clearly superior to others.

CONCLUSION

Current instruments are not suited for effective surgery in a NOTES environment. There are several important requirements for NOTES platform: 1) to provide safe access to the peritoneal cavity; 2) to provide a stable channel for instrumentation passageway and safe navigation, 3) to provide good visualization and illumination, thereby decreasing disorientation, 4) to maintain proper insufflation and suction/irrigation, and 5) to provide maneuverability and triangulation of the instruments. Effective collaborations between clinicians, engineering departments and industry are essential to maximise and expedite the innovative process in producing an optimal NOTES platform.

Natural orifice translumenal endoscopic surgery (N.O.T.E.S)

Natural orifice translumenal endoscopic surgery (N.O.T.E.S) is a technique that allows access to the peritoneal cavity through natural orifices (oral, rectal, vaginal, vesical) without passing through the anterior abdominal wall. Rapid strides have been made in developing this technique, especially in animal models. Majority of research work in this field is originating from USA, while human clinical trials are being reported from India and Southern America. Morbidly obese patients and ITU patients are two target groups where N.O.T.E.S if implemented, will have the highest potential and bearing. With increasing evidence of safe practice in human models, questions on indications and feasibility of practice need to be addressed by rigorous research, strong evidence and collaboration between surgical centers worldwide.

Totally NOTES (T-NOTES) transvaginal cholecystectomy using two endoscopes: preliminary report

BACKGROUND

Clinical applications of transvaginal Natural Orifice Transluminal Endoscopic Surgery (NOTES) are still limited in the literature, mostly case reports performed by hybrid procedures with laparoscopic assistance. Avoiding complications from incisions is the main goal for natural orifice surgery. This study reports on a technique developed at our institution that uses two endoscopes inserted into the vagina to perform a Totally NOTES (T-NOTES) transvaginal cholecystectomy, and describes preliminary results.

METHODS

IRB approval was obtained at the institution for transvaginal NOTES clinical trials, and informed consent was obtained. The technique of T-NOTES transvaginal cholecystectomy was clinically applied in four female patients with symptomatic cholelithiasis, and data were prospectively documented. Transvaginal NOTES access was obtained by direct vaginal incision, and two endoscopes were simultaneously introduced in the abdominal cavity. Dissection was accomplished with available endoscopic instruments. Ligation of cystic duct and artery was performed using endoscopic clips. Vaginal closure was achieved using the direct-vision sutured technique.

RESULTS

The technique was successfully performed in the four patients. Insufflation and spatial orientation was of good quality. Mean operative time was 210 min. There were no complications during the 30-day follow-up. Postoperative course was uneventful, and patients were released from the hospital on the first postoperative day.

CONCLUSION

Tranvaginal T-NOTES using two endoscopes provides a feasible method for natural orifice cholecystectomy using available technology. Large-series studies are needed to evaluate the results with respect to safety of the approach.

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)

BACKGROUND

Leak-resistant closure of transluminal access is a major challenge facing natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

To evaluate a hydrogen (H(2))-based leak test for assessment of transluminal-access closure integrity after NOTES procedures.

SETTING

Nine acute porcine experiments.

DESIGN AND INTERVENTION

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.

MAIN OUTCOME MEASUREMENT

Intraperitoneal H(2) concentration after gastric insufflation with H(2).

RESULTS

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.

LIMITATIONS

Nonsurvival animal experiments.

CONCLUSIONS

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.

Total transvaginal endoscopic abdominal wall hernia repair: a NOTES survival study

HYPOTHESIS

Natural orifice transluminal endoscopic surgery (NOTES) has gained widespread interest as a potentially less invasive alternative to laparoscopic surgery or, else, an evolution as the next-generation surgery. The main objective of this study was to assess the safety of transluminal abdominal wall hernia repair for potential human application by specifically investigating the feasibility and challenges of using a transvaginal approach.

DESIGN

NOTES ventral hernia repair via a transvaginal approach.

SETTING

University Hospital (National University Health System, Singapore).

PARTICIPANTS

The study utilized five female pigs (30-40 kg) between 5 and 7 months of age, which underwent abdominal wall hernia repair using a transvaginal approach.

INTERVENTION

The procedures were performed using a double-channel endoscope under general endotracheal anesthesia. A mesh was placed and fixed to the abdominal wall using standard laparoscopic and endoscopic equipment. The animals survived for 2 weeks and were then euthanized and a necropsy performed.

MAIN OUTCOME MEASURES

To assess the safety and feasibility of NOTES ventral hernia repair in a survival experimental model.

RESULTS

All of the procedures could be safely performed using the standard equipment. At the necropsy, all meshes were well in place and mild adhesions were recorded in one animal with a small abscess in the subcutaneous area.

CONCLUSION

This novel approach seems technically challenging but feasible using equipment and accessories currently available for conventional laparoscopic and interventional endoscopy with low intra-abdominal contamination and sepsis. New procedure-specific instruments and equipment need to be developed to allow the surgeon safer access and more degrees of instrument freedom.

The role of intraoperative carbon dioxide insufflating upper gastrointestinal endoscopy during laparoscopic surgery

BACKGROUND

Intraoperative endoscopy (IOE) is a useful adjunct during laparoscopic gastrointestinal (GI) surgery. However, one potential hazard of IOE is a prolonged bowel distension due to insufflated air, which may cause obstructed surgical exposure and increased postoperative abdominal pain. Recently, carbon dioxide (CO(2)), with its rapid absorptive nature, has been proven effective to minimize prolonged bowel distension in ambulatory/intraoperative colonoscopy. The objectives were to assess the feasibility, safety, and efficacy of CO(2)-insufflating upper GI IOE during laparoscopic surgery.

METHODS

A historical comparison study was performed on the initial ten consecutive patients who underwent CO(2)-insufflating upper GI IOE (CO(2)-IOE) during laparoscopic surgery. The control group consisted of the past 12 consecutive patients who underwent conventional air-insufflating upper GI IOE (air-IOE) during laparoscopic surgery. The following parameters were compared between the two groups: (1) patient demographics; (2) feasibility (% completion of IOE); (3) safety (complications related to IOE, impacts on cardiopulmonary status, including systemic blood pressure, heart rate, and end-tidal CO(2)); (4) efficacy (postoperative residual intestinal gas, time to resume oral intake, and bowel movement). The amounts of post-IOE residual intestinal gas were evaluated and classified on the immediate postoperative abdominal radiographs in a blinded manner.

RESULTS

Patient demographics were comparable between the two groups. IOE was completed in both groups without complications. Adverse effects on cardiopulmonary status were not observed during simultaneous intraperitoneal and intraluminal CO(2) insufflation. In the air-IOE group, one patient was converted to open surgery because of inadequate surgical exposure from prolonged distension of the downstream bowel. The patients in the CO(2)-IOE group had significantly lower grade of postoperative bowel distension than the control group. Postoperative oral intake was resumed earlier in the CO(2)-IOE group.

CONCLUSION

CO(2)-insufflating upper GI IOE during laparoscopic surgery is feasible, safe, and has a practical advantage in minimizing post-IOE bowel distension compared with conventional air-insufflating upper GI IOE.

Transumbilical endoscopic appendectomy in humans: on the road to NOTES: a prospective study

BACKGROUND

Natural orifice translumenal endoscopic surgery (NOTES) is the newest technique emerging in the field of surgery. There are several techniques described in the literature, though there is no standardization yet. In this paper, we describe a transumbilical approach for the endoscopic appendectomy in humans.

MATERIALS AND METHODS

Eight of 12 patients with uncomplicated appendicitis successfully underwent a transumbilical endoscopic appendectomy. Patients with a mass, abscessed or perforated appendix, previous lower abdominal surgeries, and conversion to laparoscopy (4 patients) were excluded.

RESULTS

The average age of the patients was 32.5 years. The mean operating time was 95 minutes, and the conversion rate was 33.3%. Only 1 dose of intravenous analgesics was administered postoperatively. Hospital stay was 1-3 days. The follow-ups were scheduled at 7, 30, and 90 days and 8 months. Six patients completed all the follow-ups and experienced no problems.

DISCUSSION

So far, this transumbilical approach to the appendectomy in humans has not been reported. We think that this method of approach is an effective technique by itself and an ideal "stepping stone" to NOTES, as well as helpful to train laparoscopic surgeons to make the transition to full-fledged NOTES. Unlike the transgastric or transvaginal approaches, the umbilical approach allows an easy maneuverability of the endoscope, though at the cost of an umbilical scar. The technical ease of the procedure and early outcome seem satisfactory. This technique may be considered as a "precursor" to NOTES.

Immunologic parameters during NOTES compared with laparoscopy in a randomized blinded porcine trial

BACKGROUND

It remains unclear if the natural orifice translumenal endoscopic surgery (NOTES) technique is less invasive than laparoscopy. Serum interleukins and peritoneal cellular response have been utilized to support the immunologic difference between open and laparoscopic surgery. We hypothesized that there would be no difference between cytokine levels during NOTES or laparoscopic peritoneoscopy.

METHODS

Twelve pigs were assigned to NOTES or standard laparoscopy with permuted block randomization. Each group underwent 90 min of diagnostic peritoneoscopy using CO(2) for laparoscopy and air for NOTES pneumoperitoneum. Blood draws were obtained at baseline, at procedure end, and on postoperative days (POD) 1, 2, and 7. Quantification of cytokines (IL-1b and TNF-alpha) was performed with a Duo Set Porcine enzyme-linked immunosorbent assay (ELISA). Laboratory results were captured by a technician blinded to the research question, and data analysis was performed by an investigator blinded to the procedure using t-test and repeated measures linear model. The study was approved by the institutional animal care and use committee (IACUC).

RESULTS

All procedures were successfully completed. One NOTES animal succumbed to hemorrhagic gastritis (day 3). All other animals thrived to POD 14, with no gross infections at necropsy. Animals undergoing laparoscopy had lower mean arterial pH than NOTES animals (p < 0.001). Serum and intraperitoneal white blood cell (WBC) counts were similar between the groups. Mean interleukin-1b levels at baseline, at the end of the procedure and at 48 h did not differ (0.50 and 0.31; p = 0.65). TNF-alpha levels did not differ at baseline or procedure end but increased in the NOTES group on POD 1, persisting to POD 7. Tumor necrosis factor-alpha (TNF-alpha) decreased in the laparoscopy group (p = 0.005).

CONCLUSION

Cytokines and WBC did not differ between laparoscopic and NOTES groups during the initial 24 h. These findings do not currently support the assumption that NOTES is less invasive than laparoscopy. The late TNF-alpha elevation contradicts other studies and requires further examination.

Air and fluid leak tests after NOTES procedures: a pilot study in a live porcine model (with videos)

BACKGROUND

Transluminal access site closure remains a major challenge in natural orifice transluminal endoscopic surgery (NOTES).

OBJECTIVE

Our purpose was to develop in vivo leak tests for evaluation of the integrity of transgastric access closure.

SETTINGS

Survival experiments on 12 50-kg pigs.

DESIGN AND INTERVENTIONS

After a standardized transgastric approach to the peritoneal cavity and peritoneoscopy, the gastric wall incision was closed with T-bars (Wilson-Cook Medical, Winston-Salem, NC) deployed on both sides of the incision and then cinched together. Gastrotomy closure was assessed with air and fluid leak tests. The animals were observed for 1 week and then underwent endoscopic evaluation and necropsy.

MAIN OUTCOME MEASUREMENTS

(1) Leak-proof closure of the gastric wall incision. (2) Gastric incision healing 1 week after the procedure.

RESULTS

The mean intraperitoneal pressure increased 10.7 +/- 3.7 mm Hg during gastric insufflation when the air leak test was performed before closure compared with 0.9 +/- 0.8 mm Hg after transmural closure of the transgastric access site with T-bars (P < .001). Fluid leak tests demonstrated no leakage of liquid contrast from the stomach into the peritoneal cavity after closure. Necropsy in 1 week confirmed completeness of the gastric closure in all animals with full-thickness healing and no spillage of the gastric contents into the peritoneal cavity.

LIMITATIONS

Leak tests were only evaluated on an animal model.

CONCLUSIONS

Fluid and air leak tests are simple techniques to evaluate in vivo the adequacy of the transluminal access site closure after NOTES procedures. Leak-proof gastric closure resulted in adequate tissue approximation and full-thickness healing of the gastric wall incision.

Randomized blinded trial shows relative thrombocytopenia in natural orifice translumenal endoscopic surgery compared with standard laparoscopy in a porcine survival model

BACKGROUND

Anecdotal reports of natural orifice translumenal endoscopic surgery (NOTES) procedures in patients are emerging. Whether the new procedure truly is less invasive is not known. Perioperative hematologic parameters during NOTES was compared with those during standard laparoscopy.

METHODS

For this study, 12 swine were randomized to transgastric peritoneoscopy with air or diagnostic laparoscopy using carbon dioxide. Arterial and venous catheters provided cardiopulmonary parameters and blood draws at baseline and up to 7 days postoperatively. The animals survived for 14 days. Data were analyzed by an investigator blinded to the procedure performed. Treatments were contrasted in terms of the mean outcome using a repeated measures linear model.

RESULTS

All experiments were successfully completed. No gastric leak or peritonitis resulted. One NOTES animal died of hemorrhagic gastritis on postoperative day 3 due to bleeding distant from the gastrotomy site. Two animals in the laparoscopy group and one animal in the endoscopy group experienced respiratory compromise requiring disinflation. A widening pulse pressure and lower bladder pressure were observed in the NOTES group compared with the laparoscopy group (p < 0.001). Pre- and postoperative laboratory results showed an increase in the white blood cell count (1,000/ml) from 16.83 +/- 1.94 in the laparoscopy group and 15.17 +/- 0.41 in the NOTES group at baseline to 24.17 +/- 3.25 and 23.33 +/- 3.88, respectively, on postoperative day 7, but no difference between the groups (p = 0.6). The platelet count (1,000/ml) showed a difference between the two groups, changing from 422.5 +/- 97.49 to 446.33 +/- 89.86 in the laparoscopy group and from 368 +/- 105 to 299.5 +/- 161.9 in the NOTES group (p = 0.03).

CONCLUSION

Significant differences in measured but not clinically apparent parameters were encountered. A potentially significant thrombocytopenia clinically was encountered in the NOTES group. The physiologic impact of NOTES procedures beyond the absence of abdominal incisions should be investigated further.

Flexible transgastric peritoneoscopy and liver biopsy: a feasibility study in human beings (with videos)

BACKGROUND

Multiple studies have demonstrated the feasibility of natural orifice transluminal endoscopic surgery in animal models.

OBJECTIVE

To determine the feasibility of transgastric peritoneoscopy and liver biopsy in human beings.

SETTING

Our institutional review board approved the procedures in the operating room with the patients under general anesthesia.

DESIGN AND INTERVENTIONS

During laparoscopic gastric bypass surgery a flexible endoscope was introduced into the peritoneal cavity through the gastric-wall incision. A peritoneoscopy with a liver biopsy was performed, then the flexible endoscope was withdrawn into the stomach, and gastric bypass surgery was completed laparoscopically.

PATIENTS

Three patients who were morbidly obese (mean weight 115.22 +/- 9.07 kg [254 +/- 20 lb]).

MAIN OUTCOME MEASUREMENTS

The ability to navigate a flexible endoscope inside the peritoneal cavity, to visualize the intra-abdominal organs, and to perform a liver biopsy without laparoscopic assistance.

RESULTS

It was very easy to navigate the flexible endoscope inside the abdomen by using torque, advancement, and withdrawal of the endoscopic shaft, as well as by movement of the endoscope tip. The flexible endoscope provided an excellent view and adequate illumination of the peritoneal cavity. The orientation of the flexible endoscope inside the peritoneal cavity was technically easy, even in the retroflex position. Systematic visualization of the liver, the spleen, the omentum, and the small and large intestine was easily achieved through the flexible endoscope without laparoscopic assistance. A liver biopsy was successfully completed in all cases by obtaining adequate tissue samples for histologic examination.

LIMITATION

This was a pilot feasibility study.

CONCLUSIONS

Transgastric flexible endoscopic peritoneoscopy in human beings is technically feasible, simple, and can become a valuable tool that complements and facilitates laparoscopic interventions inside the peritoneal cavity.

Design of a Compliant Endoscopic Suturing Instrument

This paper describes the initial design and optimization of a compliant endoscopic suturing instrument. The emerging field of Natural Orifice Transluminal Endoscopic Surgery (NOTES) requires innovative instruments to meet the size limitations inherent in this type of minimally invasive surgery; using compliant mechanisms is proposed as one method of meeting this requirement. The compliant design was modeled and optimized to maximize the distal opening and provide a puncture force of at least 4.6N, while being small enough to fit within a 3.3mm working channel. The design utilizes contact for stress relief and intertwining parts for added deflection. ANSYS® was used for finite element analysis including contact and nonlinear deformations. A prototype was fabricated from the optimized geometry and experimentally tested. The best geometry is predicted to have a distal opening of 14.6mm at the tips and supply a puncturing force of 4.83N. The force supplied at the tip was measured and was found to exceed the required 4.6N. The prototype successfully passed two complete sutures and qualitative results are provided. The results of the study will lead to further refinements and improvements in future designs.

Natural orifice translumenal endoscopic surgery (NOTES) transvaginal cholecystectomy in a morbidly obese patient

Transvaginal natural orifice translumenal endoscopic surgery (NOTES) is a new diagnostic and potentially therapeutic method of surgical endoscopy. The first case of NOTES transvaginal cholecystectomy in a morbid obese patient in the literature is described. IRB approval was obtained at the institution for transvaginal NOTES clinical trials. A 58-year-old female patient with cholelithiasis, hypertension, and type II diabetes, and BMI of 35.8 kg/m(2) was submitted to the technique. After transvaginal access, a two-channel gastroscope was introduced into the abdominal cavity along with a laparoscopic trocar. There were 2 umbilical punctures for use of 3 mm laparoscopic equipment. Operative time was 85 min. There was no use of postoperative analgesia, and the patient was discharged on the third postoperative day. Transvaginal NOTES is a feasible alternative method for cholecystectomy in the morbidly obese, although available technology is limited for natural orifice surgery.

Advanced endoscopic technologies

The use of endoscopy for diagnosing and treating ailments of the alimentary tract has evolved steadily over the past few decades, with tremendous growth and innovation in the past few years. Initially, endoscopy relied on rigid telescopes, direct visualization, and dangerously exothermic sources of illumination. The introduction of fiber optics, charge-coupled-device cameras, and increasingly efficient light sources has enabled researchers to investigate areas of the human gastrointestinal tract through flexible endoscopy not previously thought to be reachable without formal surgical exploration. The more recent advances in scope platforms, devices, and techniques have allowed researchers to push the envelope of endoscopic diagnostics and therapeutics to greater heights. Specific new platforms include ColonoSight and mother-daughter endoscopes such as the ShapeLock TransPort and the SpyGlass direct visualization system. Specific devices include the EndoCinch suturing system, the full-thickness Plicator procedure, Esophyx, the Stretta system, and the HALO(360) system. Specific new techniques include small-caliber endoscopy, endoscopic mucosal and submucosal resection, and natural orifice translumenal endoscopic surgery (NOTES). This article describes the most relevant recent advances in endoscopic innovation with regard to platform design, devices, and techniques anticipated to serve as the foundation for further research and design for developing generations of endoscopic technologies to come.

Reliable gastric closure after natural orifice translumenal endoscopic surgery (NOTES) using a novel automated flexible stapling device

BACKGROUND

Reliable closure of the translumenal incision is one of the main challenges facing natural orifice translumenal endoscopic surgery (NOTES). This study aimed to evaluate the use of an automated flexible stapling device (SurgASSIST) for closure of the gastrotomy incision in a porcine model.

METHODS

A double-channel gastroscope was advanced into the stomach. A gastric wall incision was made, and the endoscope was advanced into the peritoneal cavity. After peritoneoscopy, the endoscope was withdrawn into the stomach. The SurgASSIST stapler was advanced orally into the stomach. The gastrotomy edges were positioned between the opened stapler arms using two endoscopic grasping forceps. Stapler loads with and without a cutting blade were used for gastric closure. After firing of the stapler to close the gastric wall incision, x-ray with contrast was performed to assess for gastric leakage. At the end of the procedure, the animals were killed for a study of closure adequacy.

RESULTS

Four acute animal experiments were performed. The delivery and positioning of the stapler were achieved, with technical difficulties mostly due to a short working length (60 cm) of the device. Firing of the staple delivered four rows of staples. Postmortem examination of pig 1 (when a cutting blade was used) demonstrated full-thickness closure of the gastric wall incision, but the cutting blade caused a transmural hole right at the end of the staple line. For this reason, we stopped using stapler loads with a cutting blade. In the three remaining animals (pigs 2-4), we were able to achieve a full-thickness closure of the gastric wall incision without any complications.

CONCLUSIONS

The flexible stapling device may provide a simple and reliable technique for lumenal closure after NOTES procedures. Further survival studies are currently under way to evaluate the long-term efficacy of gastric closure with the stapler after intraperitoneal interventions.