Euro-NOTES Status Paper: from the concept to clinical practice

Feasibility of a novel unassisted single-channel transcolonic endoscopic appendectomy for the treatment of appendiceal lesions (with video)

BACKGROUND

Transcolonic endoscopic appendectomy (TEA) is rapidly evolving and has been reported as a minimally invasive alternative to appendectomy. We aimed to characterize the feasibility and safety of a novel unassisted single-channel TEA.

METHOD

We retrospectively investigated 23 patients with appendicitis or appendiceal lesions who underwent TEA from February 2016 to December 2022. We collected clinicopathological characteristics, procedure‑related parameters, and follow‑up data and analyzed the impact of previous abdominal surgery and traction technique.

RESULTS

The mean age was 56.0 years. Of the 23 patients with appendiceal lesions, fourteen patients underwent TEA and nine underwent traction-assisted TEA (T-TEA). Eight patients (34.8%) had previous abdominal surgery. The En bloc resection rate was 95.7%. The mean procedure duration was 91.1 ± 45.5 min, and the mean wound closure time was 29.4 ± 18.6 min. The wounds after endoscopic appendectomy were closed with clips (21.7%) or a combination of clip closure and endoloop reinforcement (78.3%), and the median number of clips was 7 (range, 3-15). Three patients (13.0%) experienced major adverse events, including two delayed perforations (laparoscopic surgery) and one infection (salvage endoscopic suture). During a median follow-up of 23 months, no residual or recurrent lesions were observed, and no recurrence of abdominal pain occurred. There were no significant differences between TEA and T-TEA groups and between patients with and without abdominal surgery groups in each factor.

CONCLUSION

Unassisted single-channel TEA for patients with appendiceal lesions has favorable short- and long-term outcomes. TEA can safely and effectively treat appendiceal disease in appropriately selected cases.

Innovations in GI-endoscopy

Gastrointestinal endoscopy covers both diagnosis and therapy. Due to its diagnostic accuracy and minimal invasiveness, several innovations have been made within the last years including artificial intelligence and endoscopic tumor resection. The present review highlights some of these innovation. In addition, a special focus is set on the experience made by our own research group trying to combine the expertise of endoscopists/ physicians as well as engineers and computer scientists.

vNOTES for adnexal procedures

This work aims to describe the technique and review all transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for adnexal procedures performed and to acknowledge vNOTES as an alternative to conventional laparoscopy. The procedure consisted of an incision in the Pouch of Douglas, insertion of a single port device, laparoscopic surgery through the device, extraction of specimens through the vagina and closure of the vaginal apex with a direct suture. Eighteen procedures have been successfully completed, 1 patient required conversion to conventional abdominal surgery due to intolerance to pneumoperitoneum. Surgeries' length range was 45-210 minutes. The estimated blood loss was less than 100 mL. The patients required minimal analgesia, were discharged the day after and had no postoperative complications. No patients complained of dyspareunia. Two patients conceived after surgery. vNOTES is a safe and desirable approach to the adnexa and a reasonable alternative to conventional laparoscopy or vaginal surgery.Impact statementWhat is already known on this subject? Natural Orifice Transluminal Surgery (NOTES) is a technique used to access the abdominal cavity through natural orifice. Compared to conventional laparoscopy, it's expected to have fewer complications.What do the results of this study add? This is one of the few works addressing vNOTES adnexal surgery, which appears to be a good alternative to conventional laparoscopy.What are the implications of these findings for clinical practice and/or further research? vNOTES may be a desirable approach to the adnexa. This work opens a door to new research regarding vNOTES in more complex gynaecologic procedures.

Randomized clinical trial on the use of a colon-occlusion device to assist rectal washout

Background

Transrectal Natural Orifice Transluminal Endoscopic Surgery is currently limited by the inherent risk of surgical site infection due to peritoneal contamination after rectotomy. Coloshield has been developed as a temporary colon occlusion device to facilitate rectal washout. However, effectiveness and safety has not been evaluated in humans.

Methods

Twenty-two patients have been randomly assigned to undergo proctological intervention with a rectal washout with and without the use of Coloshield. Patients and assessors were blinded. Boston Bowel Preparation Scale (BBPS) has been determined 30 min as well as immediately after rectal washout. Feasibility, pain, intra- and postoperative morbidity as well as bowel function and continence 6 weeks after surgery were assessed.

Results

BBPS 30 min after rectal washout with and without Coloshield was in mean 2.42 ± 1.02 and 2.12 ± 0.89 (p = 0.042). Mean BBPS immediately after rectal washout was 2.39 ± 1.02 and 2.24 ± 0.66 (p = 0.269). Mean BBPS immediately after rectal washout and 30 min thereafter did not differ (p = 0.711). Coloshield application was feasible without any complications. The median (interquartile range) numeric rating scale for pain 4 h after surgery was 1 (0–1) and 3 (0–4) (p = 0.212). Six weeks after surgery 0/11 and 1/11 patients suffered from evacuation difficulties (p = 1.0) and the median Vaizey–Wexner score was 1 (0–3) and 1 (0–2) (p = 0.360).

Conclusions

Coloshield application in humans is feasible and safe. Slight benefits in rectal preparation by washout are found when Coloshield is used. Colon occlusion by Coloshield for transrectal NOTES should be evaluated within clinical studies.

Trial registration

Clinicaltrials.gov NCT02579330

Transanal hybrid colon resection: techniques and outcomes for benign colorectal diseases

BACKGROUND

Transanal hybrid rectal and colon resection have been introduced in recent years at dedicated surgical centers. The anus is used as a natural orifice for large size access. The use of transanal hybrid colectomy techniques is still in its infancy with outcomes and unique complications being identified. The purpose of this work is the evaluation of outcomes for transanal hybrid colon resections (ta-CR), including intra operative and postoperative complications, results, and advantages.

METHODS

A prospectively maintained database was analyzed. Inclusion criteria were any patient who underwent ta-CR for rectal prolapse, slow transit, obstructive defaecation, and chronic sigmoid diverticulitis. Patients were excluded from ta-CR if BMI > 30, major previous abdominal surgery, or presence of a large inflammatory mass in diverticulitis. Transanal access was used for all operative steps requiring access of more than 5 mm, such as staplers, large graspers, and specimen retrieval. Data acquisition and analysis was performed for operative time, complications, and postoperative quality of life.

RESULTS

From 2012 to 2017, 82 patients underwent ta-CR [33 males, 49 females, median age 58 (24-80)]. Transanal-subtotal colectomy and ta-CR for constipation was performed in 12 patients; ta-CR and rectopexy in 31, and ta-CR for diverticulitis was performed in 39 patients. Conversion to traditional approach was required in 3 cases (3.6%). Intraoperative complication included 1 rectal tear requiring intervention. Post-op complications included 3 leaks requiring laparoscopic and 1 open revision, the latter developed wound infection and an incisional hernia. Gastrointestinal Quality of Life Index (GIQLI) improved significantly from preoperative 89 to postoperative 119 (p < 0.001). No patients with ta-CR without open revision developed a hernia post-op with median 18 months follow-up.

CONCLUSIONS

ta-CR is a safe and effective NOTES Hybrid technique for colorectal procedures in selected patients with benign colon disorders. GIQLI shows improvement and this technique can have the potential in preventing wound and hernia complications.

Transcolonic Perirectal NOTES Access (PNA): A feasibility study with survival in swine model

Transrectal access still has some unsolved issues such as spatial orientation, infection, access and site closure. This study presents a simple technique to perform transcolonic access with survival in a swine model series. A new technique for NOTES perirectal access to perform retroperitoneoscopy, peritoneoscopy, liver and lymphnode biopsies was performed in 6 pigs, using Totally NOTES technique. The specimens were extracted transanally. The flexible endoscope was inserted through a posterior transmural incision and the retrorectal space. Cultures of bacteria were documented for the retroperitoneal space and intra abdominal cavity after 14 days. Rectal site was closed using non-absorbable sutures. There was no bowel cleansing, nor preoperative fasting. The procedures were performed in 6 pigs through transcolonic natural orifice access using available endoscopic flexible instruments. All animals survived 14 days without complications, and cultures were negative. Histopathologic examination of the rectal closure site showed adequate healing of suture line and no micro abscesses. The results of feasibility and safety of experimental Transcolonic NOTES potentially brings new frontiers and future wider applications for minimally invasive surgery. The treatment of colorectal, abdominal and retroperitoneal diseases through a flexible Perirectal NOTES Access (PNA) is a promising new approach.

Flexible Gastro-intestinal Endoscopy - Clinical Challenges and Technical Achievements

Flexible gastro-intestinal (GI) endoscopy is an integral diagnostic and therapeutic tool in clinical gastroenterology. High quality standards for safety, patients' comfort, and efficiency have already been achieved. Clinical challenges and technical approaches are discussed in this short review.

Image enhanced endoscopy for further characterization of mucosal and vascular patterns includes dye-spray or virtual chromoendoscopy. For confocal laser endoscopy, endocytoscopy, and autofluorescence clinical value has not yet been finally evaluated. An extended viewing field provided by additional cameras in new endoscopes can augment detection of polyps behind folds. Attachable caps, flaps, or balloons can be used to flatten colonic folds for better visualization and stable position.

Variable stiffness endoscopes, radiation-free visualization of endoscope position, and different overtube devices help reducing painful loop formation in clinical routine. Computer assisted and super flexible self-propelled colonoscopes for painless sedation-free endoscopy need further research. Single-use devices might minimize the risk of infection transmission in the future.

Various exchangeable accessories are available for resection, dissection, tunneling, hemostasis, treatment of stenosis and closure of defects, including dedicated suturing devices. Multiple arm flexible devices controlled via robotic platforms for complex intraluminal and transmural endoscopic procedures require further improvement.

Novel and safer endoscopic cholecystectomy using only a flexible endoscope via single port

AIM

To apply the laparoscopic and endoscopic cooperative surgery concept, we investigated whether endoscopic cholecystectomy could be performed more safely and rapidly via only 1 port or not.

METHODS

Two dogs (11 and 13-mo-old female Beagle) were used in this study. Only 1 blunt port was created, and a flexible endoscope with a tip attachment was inserted between the fundus of gallbladder and liver. After local injection of saline to the gallbladder bed, resection of the gallbladder bed from the liver was performed. After complete resection of the gallbladder bed, the gallbladder was pulled up to resect its neck using the Ring-shaped thread technique. The neck of the gallbladder was cut using scissor forceps. Resected gallbladder was retrieved using endoscopic net forceps via a port.

RESULTS

The operation times from general anesthetizing with sevoflurane to finishing the closure of the blunt port site were about 50 min and 60 min respectively. The resection times of gallbladder bed were about 15 min and 13 min respectively without liver injury and bleeding at all. Feed were given just after next day of operation, and they had a good appetite. Two dogs are in good health now and no complications for 1 mo after endoscopic cholecystectomy using only a flexible endoscope via one port.

CONCLUSION

We are sure of great feasibility of endoscopic cholecystectomy via single port for human.

Submucosal Tunneling Endoscopic Resection (STER) and Other Novel Applications of Submucosal Tunneling in Humans

The submucosal tunneling technique was originally developed to provide safe access to the peritoneal cavity for natural orifice transluminal endoscopic surgery procedures. With this technique, the submucosal tunnel becomes the working space for partial myotomy and tumor resection. The submucosal space has come to represent the "third space" distinguished from gastrointestinal lumen (first space) and peritoneal cavity (second space). New applications continue to be developed and further clinical applications in the future are anticipated. This article summarizes the current applications of submucosal tunneling endoscopic resection for subepithelial tumors and describes other related uses of submucosal tunneling.

[Natural orifice transluminal endoscopic surgery in Germany: Data from the German NOTES registry]

BACKGROUND

The German NOTES registry (GNR) was initiated by the German Society for General and Visceral Surgery (DGAV) as a treatment and outcome database for natural orifice transluminal endoscopic surgery (NOTES).

AIM

The aim of this study was the descriptive analysis of all GNR data collected over a 5-year period since its start in 2008 with more than 3000 interventions.

MATERIAL AND METHODS

The GNR is an online database with voluntary participation available to all German-speaking clinics. Demographic data, therapy details, complications and data on the postoperative course of patients are recorded. All cases in the GNR between March 2008 and November 2013 were included in the analysis.

RESULTS

From a total of 3150 data sets 2992 (95 %) were valid and suited for the analysis. Hybrid transvaginal cholecystectomy was the most frequently used procedure (88.7 %), followed by hybrid transvaginal/transgastric appendectomy (6.1 %) and hybrid transvaginal/transrectal colon procedures (5.1 %). Intraoperative complications occurred in 1.6 %, postoperative complications in 3.7 % and conversions were reported in 1.5 %. Intraoperative bladder injuries and postoperative urinary tract infections were identified as method-specific complications of transvaginal procedures. Bowel injuries occurred as a rare (0.2 %) but potentially serious complication of transvaginal operations.

CONCLUSION

The German surgical community ensures a safe and responsible introduction of the new NOTES operation techniques with its active participation in the GNR. Despite an overall low complication rate, the high number of procedures in the GNR permitted the identification of method-specific complications. This knowledge can be used to further increase the safety of NOTES in practice.

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.

An experimental study in six fresh human cadavers using a novel approach to avoid abdominal wall incisions in total colectomy: totally transanal laparoendoscopic single-site pull-through colectomy with J-pouch creation

BACKGROUND

The use of transanal laparoscopic access to completely avoid abdominal wall incisions represents the most current evolution in minimally invasive surgery. The combination of single-site surgery and natural orifice transluminal endoscopic surgery (NOTES™) can be used for totally transanal laparoendoscopic pull-through colectomy with J-pouch creation (TLPC-J). The aim of the present study was to provide evidence for the feasibility of TLPC-J in adult human cadavers.

METHODS

TLPC-J was performed in six fresh adult human cadavers. The procedure involved endorectal submucosal dissection from 1 cm above the dentate line to a point above the peritoneal reflection, where the rectal muscle was divided circumferentially. The edge of the mucosal cuff was closed distally in order to prevent fecal contamination and the endorectal tube was placed back into the abdomen. A Triport+™ or QuadPort+™ system was introduced transanally, and it served as a multiport device (MD). Resection of the entire colon, mobilization of the distal ileal segment, and extracorporeal suture of the ileal J-loop were performed via the transanal approach. The J-pouch was created using Endo GIA™. After removal of the MD, the J-pouch was sutured to the rectal wall.

RESULTS

TLPC-J was performed in all cadavers, with a mean operation duration of 236 ± 22 min. Conversion to either transabdominal laparoscopy or laparotomy was not required in any of the cadavers. No bowel perforation or damage to other organs was observed. The use of a curved endoscope greatly facilitated visualization during transanal laparoscopic dissection for partial and total colectomy, making the procedure feasible. All specimens were retrieved through the anus, eliminating the need for additional transabdominal incisions.

CONCLUSIONS

TLPC-J was technically feasible in adult human cadavers, and abdominal wall incisions were not required. However, clinical studies are needed to determine its feasibility in living adults.

Gastrotomy Healing After Transgastric Peritoneoscopy: A Randomized Study in a Pig Model

INTRODUCTION

Reliable closure and infection prevention are the main barriers for implementation of pure transgastric peritoneoscopy. The primary aim of this study was to assess healing of over the scope clip (OTSC) closed gastrotomies.

MATERIALS AND METHODS

Pure transgastric peritoneoscopy was performed in 7 pigs. The pigs were randomized to 14 or 28 postoperative days (POD) of follow-up. Decontamination of the access route was performed before instrumentation. A full necropsy was performed. Closure was evaluated with histopathological examination of excised gastrorrhaphies.

RESULTS

Three pigs were allowed 14 POD of follow-up, and 4 pigs were allowed 28 POD of follow-up. Survival was achieved in 6 of the 7 animals; 1 pig was euthanized due to diffuse peritonitis. Based on our definition, full-thickness healing had only been achieved in a single pig allowed 28 POD. With respect to clinical relevancy, full-thickness healing was deemed achieved in 4 of 6 pigs completing follow-up and in all pigs allowed and surviving 28 POD. Access required repeated punctures and the use of several endoscopic instruments.

CONCLUSIONS

Full-thickness healing of the gastrotomy was only found in a single case when adhering to the per protocol definition. Endoscopic ultrasonography-guided access was difficult. It lacks reproducibility and needs refinement. Despite a combined decontamination regimen, infectious complications still occurred.

Transanal total mesorectal excision: a pure NOTES approach for selected patients

BACKGROUND

The concept of natural orifice transluminal endoscopic surgery (NOTES) has stimulated the development of various "incisionless" procedures. One of the most popular is the transanal approach for rectal lesions. The aims of this study were to report how we standardized NOTES technique for transanal mesorectal excision without abdominal assistance, discuss the difficulties and surgical outcomes of this technique and report its feasibility in a small group of selected patients.

METHODS

Three consecutive female patients underwent transanal NOTES rectal resection without transabdominal laparoscopic assistance for rectal lesions. Functional results were assessed with the Fecal Incontinence Quality of Life scale and the Wexner score.

RESULTS

The technical steps are described in details and complemented with a video. All procedures were completed without transabdominal laparoscopic help. The mesorectal plane was entirely dissected without any disruption, and distal and circumferential margins were tumor-free. No major complications were observed. Functional results show a significant impairment after surgery with improvement at 6 months to levels near those of the preoperative period.

CONCLUSIONS

The performance and publication of NOTES procedures are subject to much discussion. Despite the small number of patients, this procedure appears feasible and can be accomplished maintaining fecal continence and respecting oncologic principles.

Transjejunal Extraction of Gallbladder After Mini-Laparoscopic Cholecystectomy in Patients with Previous Roux-en-Y Gastric Bypass: A Small Case Series

BACKGROUND

The length of incisions on the abdominal wall directly correlates with wound-related morbidities and patient comfort. Both mini-laparoscopy (only ≤5-mm trocars) and natural orifice specimen extraction avoid larger abdominal incisions. This study described a new natural orifice translumenal endoscopic surgery (NOTES(®); American Society for Gastrointestinal Endoscopy [Oak Brook, IL] and Society of American Gastrointestinal and Endoscopic Surgeons [Los Angeles, CA]) cholecystectomy technique by combination of these two advanced laparoscopic techniques for cholelithiasis in patients who had prior laparoscopic Roux-en-Y gastric bypass (LRYGB) for obesity.

PATIENTS AND METHODS

Three patients (two males, one female; 39, 62, and 34 years old, respectively) were admitted with symptomatic cholelithiasis (multiple millimeter-sized gallstones), and all had previously had LRYGB. They were treated by mini-laparoscopic cholecystectomy using three 5-mm trocars. The gallbladder was removed through the dilated efferent limb of the jejunum, 5 cm distal from the gastrojejunostomy. Transjejunal extraction was performed under endoscopic guidance. The gallbladder in the jejenum was passed through the anastomosis and extracted with an endoscopic snare by the transoral way. The enterotomy was closed intracorporeally.

RESULTS

There was no conversion or additional trocar requirement. All the procedures were completed successfully without problems. Respective operating times were 95, 75, and 120 minutes. Only 1 patient required postoperative analgesic; the others did not. The patients started to get a liquid diet on the night of surgery and were discharged on Days 1, 1, and 2, respectively, with normal diet recommendations. There were no morbidities.

CONCLUSIONS

Mini-laparoscopic cholecystectomy is technically feasible in patients with previous LRYGB. Prior LRYGB was not an obstacle for transoral specimen extraction. The dilated efferent jejunal limb is a good alternative route for natural orifice specimen extraction. This report described the first natural orifice surgery through the small bowel.

Laparoscopic anterior resection with transanal total mesorectal excision for rectal cancer: preliminary experience and impact on postoperative bowel function

AIM

Transanal total mesorectal excision (TME) and the "down-to-up" mobilization concept might be possible alternatives to the standard TME, particularly in cases of narrow pelvis or bulky tumors in obese patients. Our aim was to test the feasibility and safety of transanal TME and to evaluate its impact on short-term functional outcome.

SUBJECTS AND METHODS

Six consecutive patients with histologically proven low/middle rectal adenocarcinoma were prospectively enrolled. All patients underwent laparoscopic anterior resection with transanal TME. Intraoperative complications, postoperative morbidity, and oncologic adequacy of the surgical specimen were evaluated in all patients. A bowel function questionnaire using information from the Wexner's score continence grading scale was administered to all patients 1 week before surgery and 6 months following operation.

RESULTS

Laparoscopically assisted transanal TME was successful in all patients. Mean operative time was 236 minutes (range, 200-270 minutes). There were no intraoperative complications. The anastomotic leak rate was 16.6%. Clear distal and circumferential margins and proper lymphadenectomy were obtained in all surgical specimens (mean number of nodes harvested, 32; range, 19-68). In no patients was a major incontinence observed; the median (range) Wexner score at 6 months after surgery was 3 (1-7).

CONCLUSIONS

Transanal TME is safe and feasible. Preliminary outcomes meet oncologic criteria. Moreover, the transanal approach does not have an adverse impact on functional outcome. Further long-term evaluation of results and clinical trials should be performed.

New trends in colorectal surgery: Single port and natural orifice techniques

Single-incision laparoscopic surgery (SILS) and natural orifice transluminal endoscopic surgery (NOTES) have rapidly gained pace worldwide, potentially replacing conventional laparoscopic surgery (CLS) as the preferred colorectal surgery technique. Currently available data mainly consist of retrospective series analyzed in four meta-analyses. Despite conflicting results and lack of an objective comparison, SILS appears to offer cosmetic advantages over CLS. However, due to conflicting results and marked heterogeneity, present data fail to show significant differences in terms of operative time, postoperative morbidity profiles, port-site complications rates, oncological appropriateness, duration of hospitalization or cost when comparing SILS with conventional laparoscopy for colorectal procedures. The application of “pure” NOTES in humans remains limited to case reports because of unresolved issues concerning the ideal access site, distant organ reach, spatial orientation and viscera closure. Alternatively, minilaparoscopy-assisted natural orifice surgery techniques are being developed. The transanal “down-to-up” total mesorectum excision has been derived for transanal endoscopic microsurgery (TEM) and represents the most encouraging NOTES-derived technique. Preliminary experiences demonstrate good oncological and functional short-term outcomes. Large-scale randomized controlled trials are now mandatory to confirm the long-term SILS results and validate transanal TEM for the application of NOTES in humans.

NOTES total mesorectal excision (TME) for patients with rectal neoplasia: a preliminary experience

BACKGROUND

Natural orifice transluminal endoscopic surgery (NOTES) and single-incision laparoscopy are emerging, minimally invasive techniques. Total mesorectal excision (TME), the gold standard treatment for patients with resectable distal rectal tumors, is usually performed in an "up-to-down" approach, either laparoscopically or via open techniques. A transanal, "down-to-up" TME has already been reported. Our NOTES variant of TME (NOTESTME) is based on a transperineal approach without any form of abdominal assistance. The aim was to reduce further the invasiveness of the procedure while optimizing the anatomical definition of the distal mesorectum. This approach may lead to reduced postoperative pain, decreased hernia formation and improved cosmesis when compared to standard laparoscopy.

METHODS

NOTESTME was attempted in 16 patients with distal rectal neoplasia (i.e., distal edge of the tumor lower than the pouch of Douglas, between 0 and 12 cm from the dentate line). Additional inclusion criteria consisted of an ASA status ≤III and the absence of previous abdominal surgery.

RESULTS

NOTESTME was completed in all patients. Additional abdominal, single-incision laparoscopic assistance was required in 6 (38 %) patients. Mean operative time was 265 min (range 155-440 min). The morbidity rate was 18.8 % (two small bowel obstructions and one pelvic abscess), requiring re-operation in each case. No leaks occurred, and the mortality rate at 30 and 90 days was 0 %. Resection margins were negative in all patients. A median of 17 nodes (range 12-81) was retrieved per specimen. Mean length of hospital stay was 10 days (range 4-29 days). Patients were followed for an average of 7 months (range 3-23 months).

CONCLUSION

NOTESTME was feasible and safe in this series of patients with mid- or low rectal tumors. The short-term mortality and morbidity rates are acceptable, with no apparent compromise in the oncological quality of the resection. Larger, randomized controlled trials with long-term follow-up are warranted.

Transanal natural orifice transluminal endoscopic surgery total mesorectal excision in animal models: endoscopic inferior mesenteric artery dissection made easier by a retroperitoneal approach

Purpose

We report the performance of natural orifice transluminal endoscopic surgery (NOTES) low anterior resection in animals using transanal total mesorectal excision (TME) with laparoscopic assistance and endoscopic inferior mesenteric artery (IMA) dissection.

Methods

Four pigs weighing 45 kg each, and one dog weighing 25 kg, underwent surgery via a transanal approach. The rectum was occluded transanally using a purse-string suture, approximately 3-4 cm from the anal verge. The rectal mucosa was incised circumferentially just distal to the purse-string. A SILS or GelPOINT port was inserted transanally. Transanal TME was assisted by laparoscopy and proceeded up to the peritoneal reflection. More proximal dissection, including IMA dissection, was performed along the retroperitoneal avascular plane by endoscopy alone and facilitated by CO₂ insufflation. The IMA was clipped and divided endoscopically. The mobilized rectosigmoid were exteriorized transanally and transected. A colorectal anastomosis was performed using a circular stapler with a single stapling technique.

Results

Endoscopic dissection of the IMA was successful in all five animals. The mean operation time was 125 minutes (range, 90-170 minutes). There were no intraoperative complications or hemodynamic instability. The mean length of the resected specimen was 14.4 cm (range, 12-16 cm).

Conclusion

A NOTES retroperitoneal approach to the IMA with CO₂ insufflation and intact peritoneal covering overcame the difficulties of retraction and exposure of endoscopic dissection in animals.

Evolving endoscopic surgery

Since the days of Albukasim in medieval Spain, natural orifices have been regarded not only as a rather repugnant source of bodily odors, fluids and excreta, but also as a convenient invitation to explore and treat the inner passages of the organism. However, surgical ingenuity needed to be matched by appropriate tools and devices. Lack of technologically advanced instrumentation was a strong deterrent during almost a millennium until recent decades when a quantum jump materialized. Endoscopic surgery is currently a vibrant and growing subspecialty, which successfully handles millions of patients every year. Additional opportunities lie ahead which might benefit millions more, however, requiring even more sophisticated apparatuses, particularly in the field of robotics, artificial intelligence, and tissue repair (surgical suturing). This is a particularly exciting and worthwhile challenge, namely of larger and safer endoscopic interventions, followed by seamless and scarless recovery. In synthesis, the future is widely open for those who use together intelligence and creativity to develop new prototypes, new accessories and new techniques. Yet there are many challenges in the path of endoscopic surgery. In this new era of robotic endoscopy, one will likely need a virtual simulator to train and assess the performance of younger doctors. More evidence will be essential in multiple evolving fields, particularly to elucidate whether more ambitious and complex pathways, such as intrathoracic and intraperitoneal surgery via natural orifice transluminal endoscopic surgery (NOTES), are superior or not to conventional techniques.

Future directions in surgery for colorectal cancer: the evolving role of transanal endoscopic surgery

SUMMARY 

The morbidity associated with radical surgery for rectal cancer has launched a revolution in increasingly less-invasive methods of resection, including a recent resurgence in transanal endoscopic surgical approaches. The next evolution in transanal surgery for rectal cancer is natural orifice translumenal endoscopic surgery (NOTES). To date, 14 series of transanal NOTES total mesorectal excision (TME) for rectal cancer have been published (n = 76). Overall, the intraoperative and postoperative complication rates of 8 and 28%, respectively, compare favorably to those expected from laparoscopic and open TME. Short-term follow-up after NOTES TME has yielded no cancer recurrence in average-risk patients. High-risk patients have cancer recurrence rates similar to those after laparoscopic TME. Overall, these early data support transanal NOTES TME as a safe and viable alternative to conventional TME. Advances in instrumentation, surgical expertise and neoadjuvant treatment may expand current indications for NOTES even further.