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.

Novel combined endoscopic and laparoscopic surgery for advanced T2 gastric cancer:Two case reports

BACKGROUND The standard treatment for advanced T2 gastric cancer(GC)is laparoscopic or surgical gastrectomy(either partial or total)and D2 lymphadenectomy.A novel combined endoscopic and laparoscopic surgery(NCELS)has recently been proposed as a better option for T2 GC.Here we describe two case studies demonstrating the efficacy and safety of NCELS.CASE SUMMARY Two T2 GC cases were both resected by endoscopic submucosal dissection and full-thickness resection and laparoscopic lymph nodes dissection.This method has the advantage of being more precise and minimally invasive compared to current methods.The treatment of these 2 patients was safe and effective with no complications.These cases were followed up for nearly 4 years without recurrence or metastasis.CONCLUSION This novel method provides a minimally invasive treatment option for T2 GC,and its potential indications,effectiveness and safety needs to be further evaluated in controlled studies.

Non-exposed endoscopic wall-inversion surgery with one-step nucleic acid amplification for early gastrointestinal tumors:Personal experience and literature review

BACKGROUND Laparoscopic and endoscopic cooperative surgery is a safe,organ-sparing surgery that achieves full-thickness resection with adequate margins.Recent studies have demonstrated the safety and efficacy of these procedures.However,these techniques are limited by the exposure of the tumor and mucosa to the peritoneal cavity,which could lead to viable cancer cell seeding and the spillage of gastric juice or enteric liquids into the peritoneal cavity.Non-exposed endoscopic wallinversion surgery(NEWS)is highly accurate in determining the resection margins to prevent intraperitoneal contamination because the tumor is inverted into the visceral lumen instead of the peritoneal cavity.Accurate intraoperative assessment of the nodal status could allow stratification of the extent of resection.One-step nucleic acid amplification(OSNA)can provide a rapid method of evaluating nodal tissue,whilst nearinfrared laparoscopy together with indocyanine green can identify relevant nodal tissue intraoperatively.AIM To determine the safety and feasibility of NEWS in early gastric and colon cancers and of adding rapid intraoperative lymph node(LN)assessment with OSNA.METHODS The patient-based experiential portion of our investigations was conducted at the General and Oncological Surgery Unit of the St.Giuseppe Moscati Hospital(Avellino,Italy).Patients with early-stage gastric or colon cancer(diagnosed via endoscopy,endoscopic ultrasound,and computed tomography)were included.All lesions were treated by NEWS procedure with intraoperative OSNA assay between January 2022 and October 2022.LNs were examined intraoperatively with OSNA and postoperatively with conventional histology.We analyzed patient demographics,lesion features,histopathological diagnoses,R0 resection(negative margins)status,adverse events,and follow-up results.Data were collected prospectively and analyzed retrospectively.RESULTS A total of 10 patients(5 males and 5 females)with an average age of 70.4±4.5 years(range:62-78 years)were enrolled in this study.Five patients were diagnosed with gastric cancer.The remaining 5 patients were diagnosed with early-stage colon cancer.The mean tumor diameter was 23.8±11.6 mm(range:15-36 mm).The NEWS procedure was successful in all cases.The mean procedure time was 111.5±10.7 min(range:80-145 min).The OSNA assay revealed no LN metastases in any patients.Histologically complete resection(R0)was achieved in 9 patients(90.0%).There was no recurrence during the follow-up period.CONCLUSION NEWS combined with sentinel LN biopsy and OSNA assay is an effective and safe technique for the removal of selected early gastric and colon cancers in which it is not possible to adopt conventional endoscopic resection techniques.This procedure allows clinicians to acquire additional information on the LN status intraoperatively.

Socioeconomic Status Impacts the Prognosis of Chronic Rhinosinusitis Treated by Endoscopic Sinus Surgery:An Observational Cohort Study in Northeast China

Objective To explore the association between socioeconomic status(SES)and postoperative outcomes in patients with chronic sinusitis(CRS)after functional endoscopic sinus surgery(ESS).Methods We conducted an observational cohort study of 1,047 patients with CRS undergoing ESS.Discharged patients were followed up to 72 weeks for all-cause recurrence events.Baseline SES was established based on occupation,education level,and family income of the patients 1 year before the operation.Kaplan–Meier method was used to calculate the recovery rate after ESS,and Cox proportional hazards regression analysis was used to evaluate the relationship between SES and prognosis.Results Patients of middle SES had lower unadjusted all-cause recurrence than those of low or high SES;24-week overall recovery rate was 90.4%[95%confidence interval(CI):89.6%–91.2%]in patients of middle SES,13.5%(95%CI:12.8%–14.2%)in patients of low SES,and 31.7%(95%CI:30.7%–32.7%)in patients of high SES(both log-rank P<0.001).After adjustment for covariates,hazard ratios(HRs)were7.69(95%CI:6.17–9.71,Ptrend<0.001)for all-cause recurrence for low SES versus middle SES,and 6.19(95%CI:4.78–7.93,Ptrend<0.001)for middle SES versus high SES.Conclusion Low SES and high SES were more associated with the worse prognosis of CRS patients after ESS than middle SES.

Endoscopic push through tragal cartilage tympanoplasty: A 10-year retrospective review of our technique and outcomes

BACKGROUND Endoscopic ear surgery(EES)provides a magnified,high-definition view of the otological surgical field.EES allows otologists to avoid surgical incisions and associated postoperative complications.It is an ideal technique for the perfor-mance and teaching of tympanoplasty.AIM To examine the efficacy of total Endoscopic Push Through Tragal Cartilage Tympanoplasty(EPTTCT),at our institution over a 10-year period.METHODS A retrospective analysis of 168 cases of EPTTCT for closure of small to medium tympanic membrane perforations from 2013-2023 was conducted.Patient sex,age range(pediatric vs adult),etiology of injury,success rate,complications,and postoperative hearing status were collected.RESULTS Graft uptake results indicated success in 94%of patients,with less than a 2%complication rate.Postoperative pure tone audiometry demonstrated hearing status improvement in 69%of patients.CONCLUSION EPTTCT has been shown to be effective in tympanic membrane perforation closures with minimal complications.This study further demonstrates the efficacy and safety of these procedures in a single-center review.

Natural orifice transluminal endoscopic surgery:Where are we going?

The foundation for natural orifice transluminal endoscopic surgery(NOTES) is to access the peritoneal and other body cavities through the wall of the alimentary tract via natural orifices,with the goal of performing procedures within the peritoneum and other cavities,without the need to make incisions in the abdominal wall.We have made great progress in the field of NOTES since the publication of the White Paper in 2006.There are still major fundamental goals as outlined by the Society of American Gastrointestinal and Endoscopic Surgeons/American Society for Gastrointestinal Endoscopy joint committee that need to be evaluated and answered before NOTES is ready for widespread clinical use.These include prevention of infection,instrument development,creation of a multitasking platform,and the ability to recognize and treat intraperitoneal complications such as hemorrhage and other physiological adverse events.In response to this need,recent abstracts and papers have focused on the management of intraoperative complications.The next phase is to focus on controlled prospective multicenter clinical trials that compare defined NOTES procedure to standard laparoscopy.The goal is to produce reliable and convincing data for the United States Food and Drug Administration,insurance companies,the physician community and the general public.At the present time,we still have many important milestones that still need to be met.Most investigators agree that a hybrid technique and not a pure NOTES practice should be advocated until devices can meet the current and new challenges in this f ield.

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.

Current developments in natural orifices transluminal endoscopic surgery:An evidence-based review

Tremendous advances have been made in recent years addressing the key obstacles to safe performance and introduction of human natural orifice transluminal endoscopic surgery (NOTES). Animal studies have focused on identifying optimal solutions to these obstacles, in particular methods of creating transluminal access,safe closure of the point of access, and development of a multitasking platform with dedicated instruments. Whether the performance data generated from these animal studies can be reproduced in humans has yet to be determined. Reports of human NOTES procedures are emerging, and the possibility of accomplishing human NOTES based on existing technology has been demonstrated. However, dedicated platforms and devices are still lacking to allow for pure NOTES procedures, and whether NOTES can deliver the postulated benef its of earlier recovery and improved cosmesis remains uncertain.

Reduction effect of bacterial counts by preoperative saline lavage of the stomach in performing laparoscopic and endoscopic cooperative surgery

AIM: To investigate the effects of gastric lavage with 2000 mL of saline in laparoscopic and endoscopic cooperative surgery.

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.

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.

Embryonic natural orifice transluminal endoscopic surgery in the treatment of severe acute pancreatitis complicated by abdominal compartment syndrome

BACKGROUND: The study aimed to estimate the value of embryonal natural orifice transluminal endoscopic surgery(ENOTES) in treating severe acute pancreatitis(SAP) complicated with abdominal compartment syndrome(ACS).METHODS: The patients, who were randomized into an ENOTES group and an operative group, underwent ENOTES and laparotomy, respectively. The results and complications of the two groups were compared.RESULTS: Enterocinesia was observed earlier in the ENOTES group than in the operative group. Acute Physiology and Chronic Health Evaluation II(APACHE II) score of patients in the ENOTES group was lower than that of the operative group on the 1st, 3rd and 5th post-operative day(P<0.05). The cure rate was 96.87% in the ENOTES group, which was statistically different from 78.12% in the operative group(P<0.05). There were significant differences in complications and mortality between the two groups(P<0.01).CONCLUSION: Compared with surgical decompression, ENOTES associated with flexible endoscope therapy is an effective and minimal invasive procedure with less complications.

Endoscopic ear surgery

Objectives:This article reviews the advantages and disadvantages of endoscopic ear surgery(EES).Method:Pubmed,Google and the Proquest Central Database at Kirikkale University were queried using the keywords"endoscopic ear surgery","ear surgery"and"endoscopy"to identify the literature needed for the review.Results:Endoscopes allow for enhanced surgical visualisation.The distal part of the apparatus is illuminated and contains lenses angled to allow a wider view of the operative area.Transcanal endoscopic techniques have transformed the external ear canal(EAC)into an operative gateway.The benefits EES can offer include wider views,enhanced imaging capabilities and increased magnification,and ways to see otherwise poorly visualisable portions of the middle ear.EES permits surgeons to operate using minimally invasive otological techniques.When compared with microscope-assisted surgery,endoscopic tympanoplasty has been shown to require a shorter operating time in some instances.There are a number of drawbacks to EES,however,which include the fact that it is a single-handed technique,that the light source may produce thermal injury and that visualisation using the endoscope is severely curtailed if bleeding is profuse.Conclusion:EES is a safe and effective technique.The current literature supports the idea that the results achieved by endoscopic methods are usually comparably beneficial to results obtained using conventional microscopic methods.

Laparoscopic and endoscopic co-operative surgery for nonampullary duodenal tumors

AIM To assess the safety and feasibility of laparoscopic and endoscopic co-operative surgery(LECS) for early nonampullary duodenal tumors.METHODS Twelve patients with a non-ampullary duodenal tumor underwent LECS at our hospital. One patient had two mucosal lesions in the duodenum. The indication for this procedure was the presence of duodenal tumors with a low risk for lymph node metastasis. In particular, the tumors included small(less than 10 mm) submucosal tumors(SMT) and epithelial mucosal tumors, such as mucosal cancers or large mucosal adenomas with malignant suspicion. The LECS procedures, such as full-thickness dissection for SMT and laparoscopic reinforcement after endoscopic submucosal dissection(ESD) for epithelial tumors, were performed for the 13 early duodenal lesions in 12 patients. Here we present the short-term outcomes and evaluate the safety and feasibility of this new technique.RESULTS Two SMT-like lesions and eleven superficial epithelial tumor-like lesions were observed. Seven and Six lesions were located in the second and third parts of the duodenum, respectively. All lesions were successfully resected en bloc. The defect in the duodenal wall was manually sutured after resection of the duodenal SMT. For epithelial duodenal tumors, the ulcer bed was laparoscopically reinforced via manual suturing after ESD. Intraoperative perforation occurred in two out of eleven epithelial tumor-like lesions during ESD; however, they were successfully laparoscopically repaired. The median operative time and intraoperative estimated blood loss were 322 min and 0 mL, respectively. Histological examination of the tumors revealed one adenoma with moderate atypia, ten adenocarcinomas, and two neuroendocrine tumors. No severe postoperative complications(Clavien-Dindo classification grade Ⅲ or higher) were reported in this series, but minor leakage secondary to pancreatic fistula occurred in one patient.CONCLUSION LECS can be a safe and minimally invasive treatment option for non-ampullary early duodenal tumors.

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.

Extrathyroidal Implantation of Thyroid Hyperplastic/neoplastic Cells after Endoscopic Thyroid Surgery

Objective To report a case of the implantation of thyroid hyperplastic or neoplastic tissue after endoscopic thyroidectomy and discuss this complication in aspects of prevalence, pathogenesis, protection, and therapies. Methods A systematic search of literature from the PubMed database was conducted for identifying eligible studies on implantation of thyroid hyperplastic or neoplastic cells after endoscopic thyroid surgery. Results Overall, 5 reported cases on patients suffering from endoscopic thyroid surgery with implantation of thyroid hyperplastic or neoplastic cells were included in the systematic review. Conclusions Unskilled surgeons, rough intraoperative surgical treatment, scarification or rupture of tumor, contamination of instruments, chimney effect, aerosolization of tumor cells may be associated with the implantation after endoscopic thyroidectomy. To minimize the risk of such complication, we should be more meticulous and strict the endoscopic surgery indications.

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.

Getting started in endoscopic ear surgery

Endoscopic ear surgery(EES) is an exciting, rapidly developing and innovative field of otologic surgery.Technically and conceptually, EES is a significant departure from traditional microscopic transcanal approaches to the middle ear and canal that has shown very positive results with respect to patient outcomes. This review serves as a primer for the otologist and otology resident embarking on EES and discusses the theory surrounding the learning process, the optical chain for endoscopic surgery as well as other important underlying principles.