Removal of a guide-wire sliding into abdominal cavity via transgastric natural orifice transluminal endoscopic surgery: A case report

BACKGROUND Guidewire slippage into the peritoneal cavity during clinical operations is extremely rare.Therefore,this paper aims to report a successful case of guidewire removal using transgastric natural orifice transluminal endoscopic surgery(NOTES).The goal is to enhance physicians'understanding of the management plan for this unique scenario and provide a valuable reference for clinical practice.CASE SUMMARY A 64-year-old man presented with abdominal distension and was diagnosed with cirrhosis combined with massive ascites.To proceed with treatment,the patient underwent ultrasound-guided peritoneal puncture and underwent catheterization and drainage.Unfortunately,a 0.035-inch guidewire slipped into the abdominal cavity during the procedure.Following a comprehensive evaluation and consultation by a multidisciplinary team,the guidewire was successfully removed using NOTES.CONCLUSION This case highlights the potential consideration of transgastric NOTES removal when encountering a foreign body,such as a guidewire,within the abdominal cavity.

Analysis of quality of life in patients after transgastric natural orifice transluminal endoscopic gallbladder-preserving surgery

BACKGROUND At present,laparoscopic cholecystectomy(LC)is the main surgical treatment for gallstones.But,after gallbladder removal,there are many complications.Therefore,it is hoped to remove stones while preserving the function of the gallbladder,and with the development of endoscopic technology,natural orifice transluminal endoscopic surgery came into being.AIM To compare the quality of life,perioperative indicators,adverse events after LC and transgastric natural orifice transluminal endoscopic gallbladder-preserving surgery(EGPS)in patients with gallstones.METHODS Patients who were admitted to The First Affiliated Hospital of Xinjiang Medical University from 2020 to 2022 were retrospectively collected.We adopted propen-sity score matching(1:1)to compare EGPS and LC patients.RESULTS A total of 662 cases were collected,of which 589 cases underwent LC,and 73 cases underwent EGPS.Propensity score matching was performed,and 40 patients were included in each of the groups.In the EGPS group,except the gastr-ointestinal defecation(P=0.603),the total score,physical well-being,mental well-being,and gastrointestinal digestion were statistically significant compared with the preoperative score after surgery(P<0.05).In the LC group,except the mental well-being,the total score,physical well-being,gastrointestinal digestion,the gastrointestinal defecation was statistically significant compared with the preoperative score after surgery(P<0.05).When comparing between groups,gastrointestinal defecation had significantly difference(P=0.002)between the two groups,there was no statistically significant difference in the total postoperative score and the other three subscales.In the surgery duration,hospital stay and cost,LC group were lower than EGPS group.The recurrence factors of gallstones after EGPS were analyzed:and recurrence was not correlated with gender,age,body mass index,number of stones,and preoperative score.CONCLUSION Whether EGPS or LC,it can improve the patient’s symptoms,and the EGPS has less impact on the patient’s defecation.It needed to,prospective,multicenter,long-term follow-up,large-sample related studies to prove.

Natural orifice translumenal endoscopic surgery: Progress in humans since white paper

Since the first description of the concept of natural orifice translumenal endoscopic surgery (NOTES), a substantial number of clinical NOTES reports have appeared in the literature. This editorial reviews the available human data addressing research questions originally proposed by the white paper, including determining the optimal method of access for NOTES, developing safe methods of lumenal closure, suturing and anastomotic devices, advanced multitasking platforms, addressing the risk of infection, managing complications, addressing challenges with visualization, and training for NOTES procedures. An analysis of the literature reveals that so far transvaginal access and closure appear to be the most feasible techniques for NOTES, with a limited, but growing transgastric, transrectal, and transesophageal NOTES experience in humans. The theoretically increased risk of infection as a result of NOTES procedures has not been substantiated in transvaginal and transgastric procedures so far. Development of suturing and anastomotic devices and advanced platforms for NOTES has progressed slowly, with limited clinical data on their use so far. Data onthe optimal management and incidence of intraoperative complications remain sparse, although possible factors contributing to complications are discussed. Finally, this editorial discusses the likely direction of future NOTES development and its possible role in clinical practice.

Natural orifice transluminal endoscopic surgery in urology: The Chinese experience

Objective:To describe the Chinese experience of natural orifice transluminal endoscopic surgery(NOTES)in urology.Methods:From December 2008 to May 2017,35 animal experiments and 305 clinical surgeries of NOTES or natural orifices specimen extractions(NOSE)were performed in China.The animal experiments included five kidney biopsies,24 nephrectomies and six partial nephrectomies.The clinical surgeries included 12 transvaginal NOSE(TV-NOSE),266 hybrid transvaginal NOTES(TV-NOTES)and 27 pure TV-NOTES.The TV-NOSE procedure was performed in five transumbilical laparoendoscopic single-site(U-LESS)nephrectomies,four suprapubic-assisted laparoendoscopic single-site surgery(SA-LESS)nephroureterectomies,and three laparoscopic radical cystectomies.The hybrid TV-NOTES procedure included 210 nephrectomies,31 adrenalectomies,eight nephroureterectomies,13 partial nephrectomies,and four heminephrectomies.The pure TV-NOTES procedure included five renal cyst decortications and 22 nephrectomies.Results:A total of 29 animal experiments were successfully performed.One partial nephrectomy was converted to standard laparoscopic surgery.Two kidney biopsies and two nephrectomies were unsuccessful.A total of 297 clinical surgeries were successfully performed.Six patients who underwent hybrid TV-NOTES were converted to open surgery.Two patients who underwent pure TV-NOTES were converted to SA-LESS.There were 22 major complications,16 occurred intraoperatively and six postoperatively.The mean visual analog score(VAS)of 48 h after the operation was 2.5 points in TV-NOSE,2.3 points in hybrid TV-NOTES and 1.7 points in pure TV-NOTES.The mean follow-up of 50.6(3.0-87.0)months showed that all patients were in good condition.The umbilicus scars were nearly invisible in TV-NOSE and hybrid TV-NOTES.The vaginal incision healed well.Conclusions:TV-NOSE and TV-NOTES are feasible,safe,and effective with little injury,low pain,fast recovery,and good cosmetic outcomes in properly selected patients.They are worth consideration for urological clinical practice.

Natural orifice transluminal endoscopic surgery:New minimally invasive surgery come of age

Although in the past two decades,laparoscopic surgery,considered as a great revolution in the minimally inva-sive surgery field,has undergone major development worldwide,another dramatic surgical revolution has quietly appeared in recent years.Ever since Kalloo's first report on transgastric peritoneoscopy in a porcine model in 2004,interest in a new surgical procedure named natural orifice transluminal endoscopic surgery(NOTES)has blossomed worldwide.Considering that a NOTES procedure could theoretically avoid any abdomi-nal incision,operation-related pain and scarring,many surgeons and endoscopists have been enthusiastic in their study of this new technique.In recent years,sev-eral NOTES studies have been carried out on porcine models and even on humans,including transvaginal cholecystectomy,transgastric appendectomy,transvagi-nal appendectomy,and transvesical peritoneoscopy.So what is the current situation of NOTES and how many challenges do we still face?This review discusses the current research progress in NOTES.

Are laparoscopic cholecystectomy and natural orifice transluminal endoscopic surgery gallbladder preserving cholecystolithotomy truly comparable?A propensity matched study

BACKGROUND Cholecystectomy is the preferred treatment option for symptomatic gallstones.However,another option is gallbladder-preserving cholecystolithotomy which preserves the normal physiological functions of the gallbladder in patients desiring to avoid surgical resection.AIM To compare the feasibility,safety and effectiveness of pure natural orifice transluminal endoscopic surgery(NOTES)gallbladder-preserving cholecystolithotomy vs laparoscopic cholecystectomy(LC)for symptomatic gallstones.METHODS We adopted propensity score matching(1:1)to compare trans-rectal NOTES cholecystolithotomy and LC patients with symptomatic gallstones.We reviewed 2511 patients with symptomatic gallstones from December 2017 to December 2020;517 patients met the matching criteria(NOTES,110;LC,407),yielding 86 pairs.RESULTS The technical success rate for the NOTES group was 98.9%vs 100%for the LC group.The median procedure time was 119 min[interquartile ranges(IQRs),95-175]with NOTES vs 60 min(IQRs,48-90)with LC(P<0.001).The frequency of post-operative pain was similar between NOTES and LC:4.7%(4/85)vs 5.8%(5/95)(P=0.740).The median duration of post-procedure fasting with NOTES was 1 d(IQRs,1-2)vs 2 d with LC(IQRs,1-3)(P<0.001).The median post-operative hospital stay for NOTES was 4 d(IQRs,3-6)vs 4 d for LC(IQRs,3-5),(P=0.092).During follow-up,diarrhea was significantly less with NOTES(5.8%)compared to LC(18.6%)(P=0.011).Gallstones and cholecystitis recurrence within a median of 12 mo(range:6-40 mo)following NOTES was 10.5%and 3.5%,respectively.Concerns regarding the presence of abdominal wall scars were present in 17.4%(n=15/86)of patients following LC(mainly women).CONCLUSION NOTES provides a feasible new alternative scar-free treatment for patients who are unwilling or unable to undergo cholecystectomy.This minimally invasive organ-sparing procedure both removes the gallstones and preserves the physiological function of the gallbladder.Reducing gallstone recurrence is essential to achieving widespread clinical adoption of NOTES.

Pure transvaginal natural orifice transluminal endoscopic surgery right hemicolectomy for colon cancer:A case report

BACKGROUND Pure natural orifice transluminal endoscopic surgery(NOTES)for colorectal cancer is a complex procedure and rarely used in clinical practice because of the ethical concerns and technical challenges,including loss of triangulation,in-line orientation,and instrument collision.Transvaginal(v)NOTES,however,can overcome these technical challenges.We report a case of pure vNOTES right hemicolectomy for colon cancer,attached with surgical video.CASE SUMMARY A 65-year-old woman with a 2-year history of intermittent diarrhea was diagnosed with ascending colon adenocarcinoma by colonoscopy and biopsy.Pure vNOTES right hemicolectomy was performed with complete mesocolic excision by well-experienced surgeons.The operative time was 200 min and the estimated blood loss was 30 mL.No intraoperative or postoperative complications occurred within 30 d after the surgery.The visual analog scale pain score on postoperative day 1 was 1 and dropped to 0 on postoperative days 2 and 3.The patient was discharged at postoperative day 6.The pathologic specimen had sufficient clear resection margins and 14 negative harvested lymph nodes.CONCLUSION vNOTES right hemicolectomy,performed by well-experienced surgeons,overcomes the technical challenges of pure NOTES and may be feasible for colon cancer.

Natural orifice transluminal endoscopic surgery in pancreatic diseases

Natural orifice transluminal endoscopic surgery (NOTES) is a surgical technique that has received considerable interest in recent years. Although minimal access surgery has increasingly replaced traditional open abdominal surgical approaches for a wide spectrum of indications, in pancreatic diseases its widespread use is limited to few indications because of the challenging and demanding nature of major pancreatic operations. Nonetheless, there have been attempts in animal models as well as in the clinical setting to perform diag- nostic and resectional NOTES for pancreatic diseases. Here, we review and comment upon the available data regarding currently analyzed and performed pancreatic NOTES procedures. Potential indications for NOTES include peritoneoscopy, cyst drainage, and necrosectomy, palliative procedures such as gastroenterostomy, as well as resections such as distal pancreatectomy or enucleation. These procedures have already been shown to be technically feasible in several studies in animal models and a few clinical trials. In conclusion, NOTES is a rapidly developing concept/technique that could potentially become an integral part of the armamentarium dealing with surgical approaches to pancreatic diseases.

Gastrointestinal tract access for urological natural orifice transluminal endoscopic surgery

We conducted a literature review of natural orifice transluminal endoscopic surgery(NOTES),focusing on urologic procedures with gastrointestinal tract access,to update on the development of this novel surgical approach.As part of the methods,a comprehensive electronic literature search for NOTES was conducted using Pub Med and Cochrane Library from March 2002 to February 2016 for papers reporting urologic procedures performed utilizing gastrointestinal tract access.A total of 11 peer-reviewed studies examining utility of gastrointestinal access for NOTES urologic procedures were noted,with the first report in 2007.The procedures reported in the studies were total/radical nephrectomy,partial nephrectomy,adrenalectomy,and prostatectomy.The transgastric approach was identified in five studies examining total/radical nephrectomy(n = 2),partial nephrectomy(n = 1),partial cystectomy(n = 1),and adrenalectomy(n = 1).Six studies evaluated transrectal approach for NOTES,describing total/radical nephrectomy(n = 3),partial nephrectomy(n = 1),robotic nephrectomy with adrenalectomy(n = 1) and prostatectomy(n = 1).Feasibility was reported in all studies.Most studies were preclinical and acute,and limited by concerns regarding restricted instrumentation and infection risk.We concluded that gastrointestinal access for urologic NOTES demonstrates promise as described by outlined feasibility studies in preclinical models.Nonetheless,clinical application awaits further advancements in surgical technology and concerns regarding infectious potential.

Natural orifice transluminal endoscopy surgery:A review

Minimally invasive surgery started spreading worldwide in 1987,when the first laparoscopic cholecystectomy was performed.Meanwhile,improvement of endoscopic equipment and instruments allowed gastroenterologists to attempt more aggressive endoluminal interventions,even beyond the wall barrier.The first transgastric peri-toneoscopy,in 2004,brought to light the concept of natural orifice transluminal endoscopic surgery(NOTES).The idea of incisionless surgery is attractive and has become a new goal for both surgeons and other people interested in this field of investigation.The authors present a review of all developments concerning NOTES,including animal studies and human experience.

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 &#x0201c;pure&#x0201d; 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 &#x0201c;down-to-up&#x0201d; 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.

Natural orifice transluminal endoscopic wedge hepatic resection with a water-jet hybrid knife in a non-survival porcine model

AIM: To explore the feasibility of a water-jet hybrid knife to facilitate wedge hepatic resection using a natural orifice transluminal endoscopic surgery (NOTES) approach in a non-survival porcine model. METHODS: The Erbe Jet2 water-jet system allows a needleless, tissue-selective hydro-dissection with a pre-selected pressure. Using this system, wedge hepatic resection was performed through three natural routes (trans-anal, trans-vaginal and trans-umbilical) in three female pigs weighing 35 kg under general anesthesia. Entry into the peritoneal cavity was via a 15-mm incision using a hook knife. The targeted liver segment was marked by an APC probe, followed by wedge hepatic resection performed using a water-jet hybrid knife with the aid of a 4-mm transparent distance soft cap mounted onto the tip of the endoscope for holding up the desired plane. The exposed vascular and ductal structures were clipped with Endoclips. Hemostasis was applied to the bleeding cut edges of the liver parenchyma by electrocautery. After the procedure, the incision site was left open, and the animal was euthanized followed by necropsy. RESULTS: Using the Erbe Jet2 water-jet system, trans-anal and trans-vaginal wedge hepatic resection was successfully performed in two pigs without laparoscopic assistance. Trans-umbilical attempt failed due to an unstable operating platform. The incision for peritoneal entry took 1 min, and about 2 h was spent on excision of the liver tissue. The intra-operative blood loss ranged from 100 to 250 mL. Microscopically, the hydro-dissections were relatively precise and gentle, preserving most vessels. CONCLUSION: The Erbe Jet2 water-jet system can safely accomplish non-anatomic wedge hepatic resection in NOTES, which deserves further studies to shorten the dissection time.

Patient and physician perception of natural orifice transluminal endoscopic appendectomy

AIM:To investigate perception of natural orifice transluminal endoscopic surgery(NOTES)as a potential technique for appendectomy.METHODS:One hundred patients undergoing endoscopy and 100 physicians were given a questionnaire describing in detail the techniques of NOTES and laparoscopic appendectomy.They were asked about the reasons for their preference,choice of orifice,and extent of complication risk they were willing to accept.RESULTS:Fifty patients(50%)and only 21 physicians(21%)preferred NOTES(P<0.001).Patients had previously heard of NOTES less frequently(7%vs73%,P<0.001)and had undergone endoscopy more frequently(88%vs 36%,P<0.001)than physicians.Absence of hernia was the most common reason for NOTES preference in physicians(80%vs 44%,P= 0.003),whereas reduced pain was the most common reason in patients(66%vs 52%).Physicians were more likely to refuse NOTES as a novel and unsure technique(P<0.001)and having an increased risk of infection(P<0.001).The preferred access site in both groups was colon followed by stomach,with vagina being rarely preferred.In multivariable modeling,those with high-school education[odds ratio(OR):2.68,95% confidence interval(CI):1.23-5.83]and prior colonoscopy(OR:2.10,95%CI:1.05-4.19)were more likely to prefer NOTES over laparoscopic appendectomy.There was a steep decline in NOTES preference with increased rate of procedural complications.Male patients were more likely to consent to their wives vaginal NOTES appendectomy than male physicians(P=0.02).CONCLUSION:The preference of NOTES for appendectomy was greater in patients than physicians and was related to reduced pain and absence of hernia rather than lack of scarring.

Peroral traction-assisted natural orifice trans-anal flexible endoscopic rectosigmoidectomy followed by intracorporeal colorectal anastomosis in a live porcine model

BACKGROUND Compared to traditional open surgery,laparoscopic surgery has become a standard approach for colorectal cancer due to its great superiorities including less postoperative pain,a shorter hospital stay,and better quality of life.In 2007,Whiteford et al reported the first natural orifice trans-anal endoscopic surgery(NOTES)sigmoidectomy using transanal endoscopic microsurgery.To date,all cases of NOTES colorectal resection have included a hybrid laparoscopic approach with the use of established rigid platforms.AIM To introduce a novel technique of peroral external traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis by using only currently available and flexible endoscopic instrumentation in a live porcine model.METHODS Three female pigs weighing 25-30 kg underwent NOTES rectosigmoid resection.After preoperative work-up and bowel preparation,general anesthesia combined with endotracheal intubation was achieved.One dual-channel therapeutic endoscope was used.Carbon dioxide insufflation was performed during the operation.The procedure of trans-anal NOTES rectosigmoidectomy included the following eight steps:(1)The rectosigmoid colon was tattooed with India ink by submucosal injection;(2)Creation of gastrostomy by directed submucosal tunneling;(3)Peroral external traction using endoloop ligation;(4)Creation of rectostomy on the anterior rectal wall by directed 3 cm submucosal tunneling;(5)Peroral external traction-assisted dissection of the left side of the colon;(6)Transanal rectosigmoid specimen transection,where an anvil was inserted into the proximal segment after purse-string suturing;(7)Intracorporeal colorectal end-toend anastomosis using a circular stapler by a single stapling technique;and(8)Closure of gastrostomy using endoscopic clips.All animals were euthanized immediately after the procedure,abdominal exploration was performed,and the air-under-water leak test was carried out.RESULTS The procedure was completed in all three animals,with the operation time ranging from 193 min to 259 min.Neither major intraoperative complications nor hemodynamic instability occurred during the operation.The length of the resected specimen ranged from 7 cm to 13 cm.With the assistance of a transumbilical rigid grasper,intracorporeal colorectal,tension-free,end-to-end anastomosis was achieved in the three animals.CONCLUSION Peroral traction-assisted transanal NOTES rectosigmoidectomy followed by intracorporeal colorectal end-to-end anastomosis is technically feasible and reproducible in an animal model and is worthy of further improvements.

Per-oral endoscopic myotomy:Major advance in achalasia treatment and in endoscopic surgery

Per-oral endoscopic myotomy(POEM)represents a natural orifice endoscopic surgery(NOTES)approach to laparoscopy Heller myotomy(LHM).POEM is arguably the most successful clinical application of NOTES.The growth of POEM from a single center in 2008 to approximately 60 centers worldwide in 2014 with several thousand procedures having been performed attests to the success of POEM.Initial efficacy,safety and acid reflux data suggest at least equivalence of POEM to LHM,the previous gold standard for achalasia therapy.Adjunctive techniques used in the West include impedance planimetry for real-time intraprocedural luminal assessment and endoscopic suturing for challenging mucosal defect closures during POEM.The impact of POEM extends beyond the realm of esophageal motility disorders as it is rapidly popularizing endoscopic submucosal dissection in the West and spawning offshoots that use the submucosal tunnel technique for a host of new indications ranging from resection of tumors to pyloromyotomy for gastroparesis.

Snare-assisted flexible endoscope in trans-gastric endoscopic gallbladder-preserving surgery:A pilot animal study

BACKGROUND Natural orifice transluminal endoscopic surgery(NOTES)gallbladder-preserving surgery by flexible endoscopy is an emerging technology.However,the gallbladder fails to obtain traction and positioning functions during the operation.AIM To evaluate the feasibility and safety of a new surgical method,“snare-assisted pure NOTES gallbladder-preserving surgery”.METHODS Eight miniature pigs were randomly divided into the experimental group[NOTES gallbladder-preserving surgery using the snare device,snare assisted(SA)]and the control group(NOTES gallbladder-preserving surgery without using the snare device,NC),with four cases in each group.The differences between the two groups of animals in operating time,operating workload,complications,adverse events,white blood cells,and liver function were determined.RESULTS No differences were found in the surgical success rate,gallbladder incision closure,white blood cell count,or liver function between the two groups.The total operating time,gallbladder incision blood loss,gallbladder disorientation time,gallbladder incision closure time,and workload scores on the National Aeronautics and Space Administration-Task Load Index were significantly reduced in the SA group(P<0.05).CONCLUSION These results indicated that snare-assisted pure NOTES gallbladder-preservation surgery using standard endoscopic instruments reduced the difficulty of operation,shortened operation time,and did not increase complications in pigs.A new method for pure NOTES gallbladder-preservation surgery was provided.

Overview of single-port laparoscopic surgery for colorectal cancers: Past, present, and the future

Single-port laparoscopic surgery (SPLS) is implemented through a tailored minimal single incision through which a number of laparoscopic instruments access. Introduction of operation-customized port system, utilization of a camera without a separate external light, and instruments with different lengths has brought the favorable environment for SPLS. However, performing SPLS still creates several hardships compared to multiport laparoscopic surgery; a single-port system inevitably leads to clashing of surgical instruments due to crowding. To overcome such difficulties, investigators has developed novel concepts and maneuvers, including the concept of inverse triangulation and the maneuvers of pivoting, spreading out dissection, hanging suture, and transluminal traction. The final destination of SPLS is expected to be a completely seamless operation, maximizing the minimal invasiveness. Specimen extraction through the umbilicus can undermine cosmesis by inducing a larger incision. Therefore, hybrid laparoscopic technique, which combined laparoscopic surgical technique with natural orifice specimen extraction (NOSE) - i.e., transvaginal or transanal route-, has been developed. SPLS and NOSE seemed to be the best combination in pursuit of minimal invasiveness. In the near future, robotic SPLS with natural orifice transluminal endoscopic surgery&#x02019;s way of specimen extraction seems to be pursued. It is expected to provide a completely or nearly complete seamless operation regardless of location of the lesion in the abdomen.

Ever-changing endoscopic treatment for early gastric cancer:Yesterday-today-tomorrow

Endoscopic resection has been an optimal treatment for selected patients with early gastric cancer(EGC) based on advances in endoscopic instruments and techniques. As endoscopic submucosal dissection(ESD) has been widely used for treatment of EGC along with expanding ESD indication, concerns have been asked to achieve curative resection for EGC while guaranteeing precise prediction of lymph node metastasis(LNM). Recently, new techniques including ESD or endoscopic full-thickness resection combined with sentinel node navigation enable minimal tumor resection and a laparoscopic lymphadenectomy in cases of EGC with high risk of LNM. This review covers the development and challenges of endoscopic treatment for EGC. Moreover, a new microscopic imaging and endoscopic techniques for precise endoscopic diagnosis and minimally invasive treatment of EGC are introduced.

Natural orifice translumenal endoscopic surgery （NOTES）： current status and challenges

Objective To give a conceptual description of natural orifice translumenal endoscopic surgery （NOTES）, review the early efforts in the NOTES field, and discuss its challenges and limitations. Data sources The data were retrieved mainly from publications listed in MEDLINE, PubMed and China Wanfang Database from 2005 to 2009. The search term was ＂NOTES＂. Study selection The articles involved in the ＂NOTES＂ study were selected and the review articles were excluded from the comparison. Results A marked increase in quantity in articles was shown each year for NOTES studies from 2006 to 2009. Animal experiments with ＂NOTES＂ have been carried out in China from 2007, and two independent ＂NOTES＂ procedures on humans were reported in 2009. Conclusion Although still in its infancy, the ＂NOTES＂ procedure is promising as another type of minimally invasive surgery and favorable alternative to current interventions.

Infection during transgastric and transvaginal natural orifice transluminal endoscopic surgery in a live porcine model

Background The infection risk of natural orifice transluminal endoscopic surgery （NOTES） is of concern. The aim of this study was to assess the safety of NOTES by investigating the intraperitoneal bacterial load during transgastric and transvaginal procedures with antiseptic or controling perioperative preparation.Methods Forty-five female pigs were randomly assigned to five equal groups： the transgastric （TG） control group （group A）, the TG middle volume gastric lavage group （group B）, the TG high volume lavage group （group C）, the transvaginal （TV） control group （group D） and the TV study group （group E）. The study groups received gastric or vaginal lavage and abdominal antimicrobial irrigation, while the control groups received neither. All animals were administered intravenous antibiotics, underwent NOTES peritoneoscopy and transumbilical laparoscopic cholecystectomy under NOTES view with sterile instruments. The viscerotomy was closed by laparoscopic suture. The animals were observed until necropsy was performed 14 days postoperatively. Quantitative bacteriologic cultures were taken from the gastric or vaginal aspirate before and after lavage; peritoneal fluid was collected before and after peritoneal irrigation and at necropsy. Results The surgical procedures were completed for all the pigs and all of them survived. The mean operative time of the TG group and the TV group was （81±27） minutes and （66±12） minutes, respectively. All animals survived for 14 days.At necropsy, significantly more peritoneal infections were noted in group A than in group D （5：9 vs. 0：9; P 〈0.05）. Nogross evidence of intra-peritoneal infection was found in groups B, C, D and E. Bacteriological evidence was seen in all pigs in group A, 7 pigs in group B, 6 pigs in group D, and none in groups C and E.Conclusions Without gastric or vaginal lavage and antibiotic peritoneal irrigation, the TG procedure has a higher infection rate than the TV access. After antiseptic preparation, the bacterial load significantly decreased in the TG group,which seems as safe as the sterile TV approach.