Inter-observer variability of experts and trainees for the diagnosis of reflux esophagitis: Comparison of linked color imaging, blue laser imaging, and white light imaging.

OBJECTIVES: Diagnosis of reflux esophagitis according to the Los Angeles classification minimal change (LA-M) has a low inter-observer agreement. We aimed to investigate whether the inter-observer agreement of reflux esophagitis was better when expert endoscopists read the endoscopic images, or when the linked color imaging (LCI) or blue laser imaging (BLI)-bright mode was used. In addition, whether the inclusion of LA-M in the definition of reflux esophagitis affected the consistency of the diagnosis was investigated. METHODS: During upper endoscopy, endoscopic images of the gastroesophageal junction were taken using white light imaging (WLI), BLI-bright, and LCI modes. Four expert endoscopists and four trainees reviewed the images to diagnose reflux esophagitis according to the modified LA classification. RESULTS: The kappa values for the inter-observer variability for the diagnosis of reflux esophagitis were poor to fair among the experts (κ = â€Š0.22, 0.17, and 0.27 for WLI, BLI-bright, and LCI, respectively) and poor among the trainees (κ = â€Š0.18, 0.08, and 0.14 for WLI, BLI-bright, and LCI). The inter-observer variabilities for the diagnosis of reflux esophagitis excluding LA-M were fair to moderate (κ = â€Š0.42, 0.35, and 0.42 for WLI, BLI-bright, and LCI) among the expert endoscopists and moderate among the trainees (κ = 0.48, 0.43, and 0.51 for WLI, BLI-bright, and LCI). CONCLUSIONS: The inter-observer agreement for the diagnosis of reflux esophagitis was very low for both the expert endoscopists and the trainees, even using BLI-bright or LCI mode. However, when reflux esophagitis LA-M was excluded from the diagnosis of esophagitis, the degree of inter-observer agreement increased.

Competency-Based Assessment Tool for Pediatric Esophagoscopy: International Modified Delphi Consensus.

OBJECTIVES/HYPOTHESIS: Create a competency-based assessment tool for pediatric esophagoscopy with foreign body removal. STUDY DESIGN: Blinded modified Delphi consensus process. SETTING: Tertiary care center. METHODS: A list of 25 potential items was sent via the Research Electronic Data Capture database to 66 expert surgeons who perform pediatric esophagoscopy. In the first round, items were rated as "keep" or "remove" and comments were incorporated. In the second round, experts rated the importance of each item on a seven-point Likert scale. Consensus was determined with a goal of 7 to 25 final items. RESULTS: The response rate was 38/64 (59.4%) in the first round and returned questionnaires were 100% complete. Experts wanted to "keep" all items and 172 comments were incorporated. Twenty-four task-specific and 7 previously-validated global rating items were distributed in the second round, and the response rate was 53/64 (82.8%) with questionnaires returned 97.5% complete. Of the task-specific items, 9 reached consensus, 7 were near consensus, and 8 did not achieve consensus. For global rating items that were previously validated, 6 reached consensus and 1 was near consensus. CONCLUSIONS: It is possible to reach consensus about the important steps involved in rigid esophagoscopy with foreign body removal using a modified Delphi consensus technique. These items can now be considered when evaluating trainees during this procedure. This tool may allow trainees to focus on important steps of the procedure and help training programs standardize how trainees are evaluated. LEVEL OF EVIDENCE: 5. Laryngoscope, 131:1168-1174, 2021.

Evaluation of long-term adherence to oesophagogastroduodenoscopy quality indicators. / Evaluación del cumplimiento a largo plazo de los indicadores de calidad en la esofagogastroduodenoscopia.

INTRODUCTION: In a previous study we demonstrated that a simple training programme improved quality indicators of Oesophagogastroduodenoscopy (OGD) achieving the recommended benchmarks. However, the long-term effect of this intervention is unknown. The aim of this study was to assess the quality of OGDs performed 3 years after of having completed a training programme. MATERIAL AND METHODS: A comparative study of 2 cohorts was designed as follows: Group A included OGDs performed in 2016 promptly after a training programme and Group B with OGDs performed from January to March 2019, this group was also divided into 2 subgroups: subgroup B1 of Endoscopists who had participated in the previous training programme and subgroup B2 of Endoscopists who had not. The intra-procedure quality indicators proposed by ASGE-ACG were used. RESULTS: A total of 1236 OGDs were analysed, 600 from Group A and 636 from Group B (439 subgroup B1 and 197 subgroup B2). The number of complete examinations was lower in Group B (566 [94.3%] vs. 551 [86.6%]; p<0.001). A significant decrease was observed in nearly all quality indicators and they did not reach the recommended benchmarks: retroflexion in the stomach (96% vs. 81%; p<0.001); Seattle biopsy protocol (86% vs. 50%; p=0.03), description of the upper GI bleeding lesion (100% vs. 62%; p<0.01), sufficient intestinal biopsy specimens (at least 4) in suspected coeliac disease (92.5% vs. 18%; p<0.001), photo documentation of the lesion (94% vs. 90%; p<0.05). Regarding the overall assessment of the procedure (including correct performance and adequate photo documentation), a significant decrease was also observed (90.5% vs. 62%; p<0.001). There were no differences between subgroups B1 and B2. CONCLUSIONS: The improvement observed in 2016 after a training programme did not prevail after 3 years. In order to keep the quality of OGDs above the recommended benchmarks, it is necessary to implement continuous training programmes.

Efficacy of traction, using a clip-with-thread, for esophageal endoscopic submucosal dissection for esophageal lesions with fibrosis in an ex vivo pig training model.

BACKGROUND/AIMS: Endoscopic submucosal dissection (ESD) of recurrent esophageal carcinoma is technically difficult to perform due to submucosal fibrosis that develops after definitive chemoradiation therapy. Therefore, our aim was to evaluate the usefulness of clip-with-thread traction for ESD of esophageal lesions with submucosal fibrosis. MATERIALS AND METHODS: Four endoscopists excised 16 lesions by ESD in an ex vivo pig training model. Mock lesions (30 mm in diameter) were created, including a 10-mm area of submucosal fibrosis in the center of each lesion. Each endoscopist performed two ESDs with traction (ESD-T) and two without traction (ESD-N). The primary outcome was the time required for submucosal dissection. Secondary outcomes were the rate of en bloc (complete) resection and perforation during the procedure, and the total amount of solution injected. RESULTS: All esophageal ESDs were completed. The median dissection time was significantly shorter for the ESD-T group (median 12.5 min, interquartile range 10.2-14.5) when comparing to the ESD-N group (median 18.0 min, interquartile range 14.6-19.2) (P=0.040). The en bloc resection rate was 100% in both groups, with a rate of complete resection of 87.5% and a rate of perforation of 37.5% for both groups. The median amount of solution injected was not significantly different between the ESD-T (18.0 ml) and ESD-N (20.5 ml) groups (P=0.526). CONCLUSION: Clip-with-thread traction improved the performance of ESD for lesions with submucosal fibrosis. However, the method might not reduce the risk of perforation, which remains an important clinical issue to resolve.

An Interactive Web-Based Educational Tool Improves Detection and Delineation of Barrett's Esophagus-Related Neoplasia.

BACKGROUND & AIMS: Endoscopic detection of early Barrett's esophagus-related neoplasia (BORN) is a challenge. We aimed to develop a web-based teaching tool for improving detection and delineation of BORN. METHODS: We made high-definition digital videos during endoscopies of patients with BORN and non-dysplastic Barrett's esophagus. Three experts superimposed their delineations of BORN lesions on the videos using special tools. In phase one, 68 general endoscopists from 4 countries assessed 4 batches of 20 videos. After each batch, mandatory feedback compared the assessors' interpretations with those from experts. These data informed the selection of 25 videos for the phase 2 module, which was completed by 121 new assessors from 5 countries. A 5-video test batch was completed before and after scoring of the four 5-video training batches. Mandatory feedback was as in phase 1. Outcome measures were scores for detection, delineation, agreement delineation, and relative delineation of BORN. RESULTS: A linear mixed-effect model showed significant sequential improvement for all 4 outcomes over successive training batches in both phases. In phase 2, median detection rates of BORN in the test batch increased by 30% (P < .001) after training. From baseline to the end of the study, there were relative increases in scores of 46% for detection, 129% for delineation, 105% for agreement delineation, and 106% for relative delineation (all, P < .001). Scores improved independent of assessors' country of origin or level of endoscopic experience. CONCLUSIONS: We developed a web-based teaching tool for endoscopic recognition of BORN that is easily accessible, efficient, and increases detection and delineation of neoplastic lesions. Widespread use of this tool might improve management of Barrett's esophagus by general endoscopists.

Dedicated Barrett's surveillance sessions managed by trained endoscopists improve dysplasia detection rate.

Background and study aim Barrett's esophagus (BE)-associated dysplasia is an important marker for risk of progression to esophageal adenocarcinoma (EAC) and an indication for endoscopic therapy. However, BE surveillance technique is variable. The aim of this study was to assess the effect of dedicated BE surveillance lists on dysplasia detection rate (DDR). Patients and methods This was a prospective study of patients undergoing BE surveillance at two hospitals - community (UHL) and upper gastrointestinal center (GSTT). Four endoscopists (Group A) were trained in Prague classification, Seattle protocol biopsy technique, and lesion detection prior to performing BE surveillance endoscopies at both sites, with dedicated time slots or lists. The DDR was then compared with historical data from 47 different endoscopists at GSTT and 24 at UHL (Group B) who had undertaken Barrett's surveillance over the preceding 5-year period. Results A total of 729 patients with BE underwent surveillance endoscopy between 2007 and 2012. There was no significant difference in patient age, sex, or length of BE between the two groups. There was a significant difference in detection rate of confirmed indefinite or low grade dysplasia and high grade dysplasia (HGD)/EAC between the two groups: 18 % (26 /142) Group A vs. 8 % (45/587) in Group B (P  < 0.001). Documentation of Prague criteria and adherence to the Seattle protocol was significantly higher in Group A. Conclusion This study demonstrated that a group of trained endoscopists undertaking Barrett's surveillance on dedicated lists had significantly higher DDR than a nonspecialist cohort. These findings support the introduction of dedicated Barrett's surveillance lists.

Development and validation of a training module on the use of acetic acid for the detection of Barrett's neoplasia.

Background and study aims Acetic acid chromoendoscopy (AAC) enhances the ability to correctly identify Barrett's neoplasia, and is increasingly used by both expert and nonexpert endoscopists. Despite its increasing use, there is no validated training strategy to achieve competence. The aims of our study were to develop a validated training tool in AAC-assisted lesion recognition, to assess endoscopists' baseline knowledge of AAC-assisted lesion recognition, and to evaluate the efficacy and impact of this training tool. Methods A validated assessment of 40 images and 20 videos was developed. A total of 13 endoscopists with experience of Barrett's endoscopy but no formal training in AAC were recruited to the study. Participants underwent: baseline assessment 1, online training, assessment 2, interactive seminar, assessment 3. Results Baseline assessment demonstrated a sensitivity of 83 % and a negative predictive value (NPV) of 83 %. The online training intervention significantly improved sensitivity to 95 % and NPV to 94 % (P < 0.01). Further improvement was seen after a 1-day interactive seminar including live cases, with sensitivity increasing to 98 % and NPV to 97 %. Conclusions The data demonstrate the need for training in AAC-assisted lesion recognition as baseline performance, even by Barrett's experts, was poor. The online training and testing tool for AAC for Barrett's neoplasia was successfully developed and validated. The training intervention improved performance of endoscopists to meet ASGE PIVI standards. The training tool increases the endoscopist's degree of confidence in the use of AAC. The training tool also leads to shift in attitudes of endoscopists from Seattle protocol towards AAC-guided biopsy protocol for Barrett's surveillance.

Development and evaluation of a rigid esophagoscopy simulator for residency training.

OBJECTIVES/HYPOTHESIS: Rigid esophagoscopy is performed less frequently by resident trainees. Nonetheless, it remains important for certain indications, including foreign body extraction. This study describes the construction of a simulator and evaluates its utility in training residents. STUDY DESIGN: Simulator development, fabrication, and procedural evaluation of postgraduate trainees. METHODS: A simulator was developed and constructed in collaboration with a biomedical engineering team. Residents with varied experience in upper aerodigestive procedures performed rigid esophagoscopy on the model. Key steps and Accreditation Council for Graduate Medical Education's Objective Structured Assessment of Technical Skills (OSATS) criteria for rigid esophagoscopy were evaluated by a faculty surgeon. Pressure measurements were obtained from force sensors at the tip of the endoscope and incisors. RESULTS: Fourteen trainees were evaluated. Operative rigid esophagoscopy and direct laryngoscopy case numbers were noted for each subject. OSATS scores and key steps of the procedure correlated with resident experience (R(2) = 0.75, P < .0001 and R(2) = 0.66, P < .001, respectively). Maximal pressure exerted on the simulator esophagus by the esophagoscope was inversely correlated with case number and was statistically significant (R(2) = 0.51, P = .02), whereas length of procedure did not correlate (R(2) = 0.04, P = .49). Maximal pressure on the incisors did not correlate (R(2) = 0.25, P = .15). CONCLUSIONS: A simulator for training residents to perform rigid esophagoscopy was developed and utilized by a faculty proctor to objectively evaluate trainees. OSATS scores, performance of key procedural steps, and pressure exerted on the simulator tissue correlated with upper aerodigestive cases performed, demonstrating validity of the simulator. LEVEL OF EVIDENCE: NA Laryngoscope, 126:616-619, 2016.

Randomized controlled trial of self-directed versus in-classroom teaching of narrow-band imaging for diagnosis of Barrett's esophagus-associated neoplasia.

BACKGROUND AND AIMS: Previous studies have shown that narrow-band imaging (NBI) can be taught to inexperienced gastroenterologists. However, it is unknown whether in-person training is more effective than self-directed training. The objective of this study was to compare the accuracy of diagnosing Barrett's esophagus (BE)-associated neoplasia by trainees with no prior NBI experience between in-classroom and self-directed didactic training programs. METHODS: This was a randomized controlled trial that took place at 2 tertiary-care medical centers, involving 33 participants--12 second-year medical students, 8 first-year gastroenterology fellows, 7 second-year gastroenterology fellows, and 6 third-year gastroenterology fellows. A teaching module was developed for all participants to review. Half of the participants were taught in a classroom setting by an endoscopist with expertise in NBI, whereas the other participants were in a self-directed group that received an automated version of the presentation with audio commentary. Participants completed a test of 40 randomized NBI images, predicting the histology and indicating their confidence levels in the diagnosis. RESULTS: There was no difference in accuracy between the in-classroom and self-directed groups (57.5% vs 57.2%; P = 1.0). The in-classroom group had a significantly higher percentage of high-confidence answers (57.2% vs 41.1%; P ≤ .01), but there was no significant difference in accuracy with these high-confidence answers (60.7% vs 66.4%; P = .34). There was no significant difference in overall accuracy or accuracy with high-confidence predictions between the 2 study sites (57.4% vs 55.9%, P = .58; 63.1% vs 61.4%, P = .69) or between gastroenterology fellows and medical students (57.8% vs 54.6%, P = .27; 62.8% vs 60.8%, P = .62). CONCLUSIONS: The overall accuracy of predicting NBI patterns in BE were modest in our study participants, and there was no difference between self-directed and in-classroom didactic training. Self-directed learning of NBI is adequate for teaching NBI to trainees.

In-class didactic versus self-directed teaching of the probe-based confocal laser endomicroscopy (pCLE) criteria for Barrett's esophagus.

BACKGROUND AND AIMS: Optimal teaching methods for disease recognition using probe-based confocal laser endomicroscopy (pCLE) have not been developed. Our aim was to compare in-class didactic teaching vs. self-directed teaching of Barrett's neoplasia diagnosis using pCLE. METHODS: This randomized controlled trial was conducted at a tertiary academic center. Study participants with no prior pCLE experience were randomized to in-class didactic (group 1) or self-directed teaching groups (group 2). For group 1, an expert conducted a classroom teaching session using standardized educational material. Participants in group 2 were provided with the same material on an audio PowerPoint. After initial training, all participants graded an initial set of 20 pCLE videos and reviewed correct responses with the expert (group 1) or on audio PowerPoint (group 2). Finally, all participants completed interpretations of a further 40 videos. RESULTS: Eighteen trainees (8 medical students, 10 gastroenterology trainees) participated in the study. Overall diagnostic accuracy for neoplasia prediction by pCLE was 77 % (95 % confidence interval [CI] 74.0 % - 79.2 %); of predictions made with high confidence (53 %), the accuracy was 85 % (95 %CI 81.8 % - 87.8 %). The overall accuracy and interobserver agreement was significantly higher in group 1 than in group 2 for all predictions (80.4 % vs. 73 %; P = 0.005) and for high confidence predictions (90 % vs. 80 %; P < 0.001). Following feedback (after the initial 20 videos), the overall accuracy improved from 73 % to 79 % (P = 0.04), mainly driven by a significant improvement in group 1 (74 % to 84 %; P < 0.01). Accuracy of prediction significantly improved with time in endoscopy training (72 % students, 77 % FY1, 82 % FY2, and 85 % FY3; P = 0.003). CONCLUSION: For novice trainees, in-class didactic teaching enables significantly better recognition of the pCLE features of Barrett's esophagus than self-directed teaching. The in-class didactic group had a shorter learning curve and were able to achieve 90 % accuracy for their high confidence predictions.

Learning endoscopic resection in the esophagus.

BACKGROUND: Endoscopic resection is the cornerstone of endoscopic management of esophageal early neoplasia. However, endoscopic resection is a complex technique requiring knowledge and expertise. Our aims were to identify the most important learning points in performing endoscopic resection in a training setting and to provide information on how to improve endoscopic resection technique. METHODS: Six gastroenterologists at centers with multidisciplinary expertise in upper gastrointestinal oncology participated in a structured endoscopic resection training program, consisting of four training days with lectures and hands-on training on live pigs, further one-to-one hands-on training days, and written feedback (by an expert) on videos of unsupervised endoscopic resection procedures. The first 20 endoscopic resections of each participant were prospectively registered. Ninety learning points were independently identified by participants using a standardized questionnaire and by an expert providing written feedback on 33 unsupervised endoscopic resection videos. Three expert endoscopists selected and ranked the most important learning points in a consensus meeting. Results. The top 10 tips (illustrated by unique videos of three perforations) were: (1) allow time for inspection and use a high-definition endoscope; (2) create a preprocedural plan by placing electrocoagulation markings; (3) know the management of bleeding; (4) optimize the endoscopic view by repeatedly cleaning out stomach and target area; (5) use a therapeutic endoscope during resection; (6) always perform a test suction; (7) keep instruments close to the tip; (8) lift edges in piecemeal endoscopic cap resections; (9) know the management of perforation; (10) pin specimens down. CONCLUSIONS: This study summarized the most important learning points for performing endoscopic resection encountered during a structured endoscopic resection training program.

[Surgical Simulation Models for Sialendoscopy]. / Trainingsmodelle für die Sialendoskopie.

OBJECTIVE: Different simulation models are in use to teach the technique of sialendoscopy. Only a few reports in literature deal with this topic with no comparison having been published, yet. We therefore asked sialendoscopy training course participants about our applied models by using a questionnaire. Material und Methods: A tube-, a pepper-, a porcine kidney-, and a pig head-model were developed as training models and used during 6 consecutive practical sialendoscopy courses from 2012 to 2014. Participants were asked to answer a questionnaire specifically designed to assess the value of the different training models. RESULTS: All respondents (n=61) rated all training models positively. However, porcine kidney- and pig head-models were described to be superior, especially with respect to realistic simulation. Intubation of the papilla can be practised sufficiently only in the pig head-model. The tube- and peppers-models have the advantage of being less expensive, easier to handle and cleaner. CONCLUSIONS: The models described are all useful in learning the sialendoscopy technique. However, they have distinct advantages and disadvantages making a combination of different models useful.

The learning effect of a training programme on the diagnosis of oesophageal lesions by narrow band imaging magnification among endoscopists of varying experience.

BACKGROUND: Magnifying narrow-band imaging using intra-epithelial papillary capillary loop analysis has been confirmed as a promising diagnostic modality for oesophageal lesions. Little is known about its learning curve. AIM: To evaluate the effect of a training programme on the diagnosis of oesophageal lesions by different modalities among endoscopists of varying experience. METHODS: We divided endoscopists into three groups based on their experience. A 2-h training programme on magnifying narrow-band imaging and intra-epithelial papillary capillary loop patterns was provided to trainees. They evaluated the test images and suggested diagnoses both before and after training. Diagnostic accuracy and interobserver agreement of three modalities were analysed. RESULTS: The diagnostic accuracies of magnifying narrow-band imaging for differentiating oesophageal neoplastic lesions and predicting lesion depth were significantly improved in less-experienced (92.8% vs. 55.9%, 63.8% vs. 17.5%) and non-experienced endoscopist groups (84.2% vs. 47.4%, 50% vs. 10%), and kappa (κ) values for both groups achieved good agreement after training (0.76 vs. 0.43, 0.68 vs. 0.24, respectively), all P<0.05. CONCLUSION: Magnifying narrow-band imaging could be learnt easily and rapidly by beginners. For diagnosis of oesophageal neoplastic lesions, our training programme improved the diagnostic skill of less-experienced endoscopists to the level of highly experienced endoscopists.

Use of flexible esophagoscopy by otolaryngologists.

OBJECTIVES: We used questionnaires to determine current practice patterns for esophagoscopy by otolaryngologists in the United States, with attention to foreign body management. METHODS: A 10-item questionnaire designed to determine the prevalence of flexible esophagoscopy use among otolaryngologists, with a particular focus on foreign body removal, was created and sent via e-mail to all members of the American Academy of Otolaryngology-Head and Neck Surgery. A second, 6-question survey to assess the level of resident training in flexible esophagoscopy was similarly created and sent to all directors of US otolaryngology residency programs. RESULTS: There were a total of 160 respondents to the first survey from all geographic regions, most of whom were in group private practice. Overall, only 21.3% of the respondents were trained to perform flexible esophagoscopy during residency, whereas 43% of those who graduated after 1990 received this training. Most respondents performed flexible esophagoscopy without sedation in the office setting. The most common indications were evaluation of dysphagia, screening for complications of laryngopharyngeal reflux, and panendoscopy for head and neck cancer. Nearly 70% of the respondents were either primarily responsible for foreign body management at their institution or shared this responsibility with a gastroenterology department. Eighty-four percent used the rigid esophagoscope alone for this purpose. More than three quarters of otolaryngology residency programs currently include flexible esophagoscopy in their training, which is performed equally in the operating room and in the office; most favor rigid esophagoscopy for foreign body retrieval but use both techniques. CONCLUSIONS: There has been a rapid increase in the use of flexible esophagoscopy by otolaryngologists. The majority of residency programs currently include flexible esophagoscopy in their training. Otolaryngologists play a major role in esophageal foreign body management and primarily use the rigid esophagoscope for this purpose.

Per-oral endoscopic myotomy (POEM) for esophageal achalasia.

Per-oral endoscopic myotomy (POEM) is a new minimally invasive endoscopic treatment for achalasia. Since the first modern human cases were published in 2008, around 2,000 cases have been performed worldwide. This technique requires advanced endoscopic skills and a learning curve of at least 20 cases. POEM is highly successful with over 90 % improvement in dysphagia while offering patients the advantage of a low impact endoscopic access. The main long-term complication is gastroesophageal reflux (GER) with an estimated incidence of 35 %, similar to the incidence of GER post-laparoscopic Heller with fundoplication. Although POEM represents a paradigm shift in the treatment of achalasia, more long-term data are clearly needed to further define its role in the treatment algorithm of this rare disease.

Development of a program to train physician extenders to perform transnasal esophagoscopy and screen for Barrett's esophagus.

BACKGROUND & AIMS: Screening for Barrett's esophagus (BE) and esophageal adenocarcinoma is not recommended because it was not found to be cost effective. However, physician extenders (PEs) are able to perform unsedated procedures; their involvement might reduce the costs of BE screening. We examined the feasibility of training PEs to independently perform transnasal esophagoscopy (TNE) and screen patients for BE and measured their learning curve. METHODS: Two PEs at a Veterans Affairs (VA) medical center underwent a structured didactic training program and observed nasopharyngoscopies before performing TNE under the supervision of attending endoscopists. Individual technical and cognitive components of TNE were rated on a 9-point structured scale. Learning curves were constructed using cumulative summation. Once the PEs were judged to be technically competent, each PE performed 10 independent videotaped TNEs, which were graded. RESULTS: Both PEs identified anatomic landmarks after 18 consecutive procedures. PE1 and PE2 performed satisfactory nasal intubations after 20 and 25 procedures and esophageal intubations after 29 and 35 procedures, respectively. They acquired overall competence after supervised training on 43 and 47 procedures, respectively. CONCLUSIONS: We developed a program at a VA medical center to train PEs to perform TNE to screen for BE. The PEs were able to perform TNE and recognize esophageal landmarks independently after a modest number of supervised procedures.