Long-Term Brain Structure and Cognition Following Bariatric Surgery.

Importance: Weight loss induced by bariatric surgery (BS) is associated with improved cognition and changed brain structure; however, previous studies on the association have used small cohorts and short follow-up periods, making it difficult to determine long-term neurological outcomes associated with BS. Objective: To investigate long-term associations of weight loss after BS with cognition and brain structure and perfusion. Design, Setting, and Participants: This cohort study included participants from the Bariatric Surgery Rijnstate and Radboudumc Neuroimaging and Cognition in Obesity study. Data from participants with severe obesity (body mass index [BMI; calculated as weight in kilograms divided by height in meters squared] >40, or BMI >35 with comorbidities) eligible for Roux-en-Y gastric bypass and aged 35 to 55 years were enrolled from a hospital specialized in BS (Rijnstate Hospital, Arnhem, the Netherlands). Participants were recruited between September 2018 and December 2020 with follow-up till March 2023. Data were collected before BS and at 6 and 24 months after BS. Data were analyzed from March to November 2023. Exposure: Roux-en-Y gastric bypass. Main Outcomes and Measures: Primary outcomes included body weight, BMI, waist circumference, blood pressure, medication use, cognitive performance (20% change index of compound z-score), brain volumes, cortical thickness, cerebral blood flow (CBF), and spatial coefficient of variation (sCOV). Secondary outcomes include cytokines, adipokines, depressive symptoms (assessed using the Beck Depression Inventory), and physical activity (assessed using the Baecke Questionnaire). Results: A total of 133 participants (mean [SD] age, 46.8 [5.7] years; 112 [84.2%] female) were included. Global cognition was at least 20% higher in 52 participants (42.9%) at 24 months after BS. Compared with baseline, at 24 months, inflammatory markers were lower (mean [SD] high-sensitivity C-reactive protein: 4.77 [5.80] µg/mL vs 0.80 [1.09] µg/mL; P < .001), fewer patients used antihypertensives (48 patients [36.1%] vs 22 patients [16.7%]), and patients had lower depressive symptoms (median [IQR] BDI score: 9.0 [5.0-13.0] vs 3.0 [1.0-6.0]; P < .001) and greater physical activity (mean [SD] Baecke score: 7.64 [1.29] vs 8.19 [1.35]; P < .001). After BS, brain structure and perfusion were lower in most brain regions, while hippocampal and white matter volume remained stable. CBF and sCOV did not change in nucleus accumbens and parietal cortex. The temporal cortex showed a greater thickness (mean [SD] thickness: 2.724 [0.101] mm vs 2.761 [0.007] mm; P = .007) and lower sCOV (median [IQR] sCOV: 4.41% [3.83%-5.18%] vs 3.97% [3.71%-4.59%]; P = .02) after BS. Conclusions and Relevance: These findings suggest that BS was associated with health benefits 2 years after surgery. BS was associated with improved cognition and general health and changed blood vessel efficiency and cortical thickness of the temporal cortex. These results may improve treatment options for patients with obesity and dementia.

Anti-Xa Levels in Morbidly Obese Patients Using Apixaban or Rivaroxaban, Before and After Bariatric Surgery.

BACKGROUND: Despite limited evidence about the efficacy and safety of anticoagulation in patients post bariatric surgery, both vitamin K antagonists (VKA) and direct-acting oral anticoagulants (DOACs) are commonly prescribed. AIM: To evaluate plasma anti-Xa levels of DOACs in morbidly obese (MO) patients before and after a Roux-en-Y gastric bypass (RYGB) procedure. PATIENTS AND METHODS: Retrospective, cross-sectional, and longitudinal study of anti-Xa activity of apixaban or rivaroxaban in MO patients (N = 41). RESULTS: Preoperative analysis of plasma anti-Xa levels were within the normal range in patients using apixaban (n = 29; body mass index [BMI] 44.5 ± 5.1 kg/m2) as well as those using rivaroxaban (n = 12; BMI 42.6 ± 5.9 kg/m2). Postoperative anti-Xa levels of apixaban were all within the therapeutic range, whereas anti-Xa levels of rivaroxaban were subtherapeutic in nine out of 14 (64%) patients. Perioperative longitudinal follow-up in patients using apixaban (n = 18) showed no significant change in anti-Xa levels after RYGB. CONCLUSION: Plasma anti-Xa levels of apixaban in MO patients remained within the therapeutic range up to a body weight of 144 kg. In patients using rivaroxaban, no statistically significant relation between anti-Xa levels and bodyweight was found. After RYGB, plasma anti-Xa levels of apixaban were unaffected, whereas plasma anti-Xa levels of rivaroxaban tended to become subtherapeutic.

Continuous vital sign monitoring using a wearable patch sensor in obese patients: a validation study in a clinical setting.

Our aim was to determine the agreement of heart rate (HR) and respiratory rate (RR) measurements by the Philips Biosensor with a reference monitor (General Electric Carescape B650) in severely obese patients during and after bariatric surgery. Additionally, sensor reliability was assessed. Ninety-four severely obese patients were monitored with both the Biosensor and reference monitor during and after bariatric surgery. Agreement was defined as the mean absolute difference between both monitoring devices. Bland Altman plots and Clarke Error Grid analysis (CEG) were used to visualise differences. Sensor reliability was reflected by the amount, duration and causes of data loss. The mean absolute difference for HR was 1.26 beats per minute (bpm) (SD 0.84) during surgery and 1.84 bpm (SD 1.22) during recovery, and never exceeded the 8 bpm limit of agreement. The mean absolute difference for RR was 1.78 breaths per minute (brpm) (SD 1.90) during surgery and 4.24 brpm (SD 2.75) during recovery. The Biosensor's RR measurements exceeded the 2 brpm limit of agreement in 58% of the compared measurements. Averaging 15 min of measurements for both devices improved agreement. CEG showed that 99% of averaged RR measurements resulted in adequate treatment. Data loss was limited to 4.5% of the total duration of measurements for RR. No clear causes for data loss were found. The Biosensor is suitable for remote monitoring of HR, but not RR in morbidly obese patients. Future research should focus on improving RR measurements, the interpretation of continuous data, and development of smart alarm systems.

Implementation of robot-assisted total mesorectal excision by multiple surgeons in a large teaching hospital: Morbidity, long-term oncological and functional outcome.

BACKGROUND: Robot-assisted total mesorectal excision (TME) might offer benefits in less morbidity, better functional and long-term outcome over laparoscopic TME. METHODS: All consecutive patients undergoing robot-assisted TME for rectal cancer during implementation between May 2015 and December 2019 performed by five surgeons in a single centre were included. Outcomes included local recurrence rate at 3 years, conversion rate, circumferential resection margin (CRM) positivity rate, 30-day postoperative morbidity and outcomes of low anterior resection syndrome (LARS) questionnaires. RESULTS: In 105 robot-assisted TME, local recurrence rate at 3 years was 7.4%, conversion to open surgery rate was 8.6%, CRM positivity rate was 5.7%, 73.3% had good quality specimen, postoperative morbidity rate was 47.6% and anastomotic leakage rate was 9.0%. Incidence of major LARS was 55.3%. CONCLUSIONS: results of this study described acceptable morbidity, functional and long-term outcome during implementation of robotic TME for rectal cancer by multiple surgeons in a single centre.

Efficacy and Safety of 100 Laparoscopy-Assisted Transgastric Endoscopic Retrograde Cholangiopancreatography Procedures in Patients with Roux-en-Y Gastric Bypass.

PURPOSE: Laparoscopy-assisted transgastric endoscopic retrograde cholangiopancreatography (LAERCP) is an alternative for the anatomically challenging conventional ERCP in patients with a Roux-en-Y gastric bypass (RYGB) as it allows access to the biliary tree via the gastric remnant. We investigated the efficacy and safety of LAERCP. MATERIAL AND METHODS: We retrospectively reviewed all charts from RYGB patients who underwent a LAERCP between January 2009 and August 2019 in a non-academic referral center for bariatric surgery. Patients who underwent pancreatic therapy were excluded. We collected demographic, clinical, and outcome data. An adverse event was defined as any complaint related to the LAERCP up to 30 days after the procedure and graded according to the ASGE lexicon. RESULTS: We identified 100 LAERCP in 86 patients with RYGB (70% female, median age 54 years). Same-session cholecystectomy was performed in 35 LAERCP (35%). The papilla of Vater was visualized in 100% of LAERCP with a therapeutic success rate of 94%. Stone extraction succeeded in 88.8% and sphincterotomy was performed in 96.7%. We identified 30 adverse events in 28 procedures, of which eight endoscopy-related, 14 laparoscopy-related, and eight non-specified (f.i. fever, allergic reaction). In total, six severe adverse events were reported concerning post-ERCP pancreatitis (n = 2), laparoscopy-related hemorrhage (n = 1), abscess (n = 1), shock (n = 1), and pneumonia (n = 1). No patient died due to LAERCP. CONCLUSION: LAERCP is an effective and relatively safe procedure for biliary diseases in patients with RYGB.

Weight loss and malnutrition after conversion of the primary Roux-en-Y gastric bypass to distal gastric bypass in patients with morbid obesity.

BACKGROUND: After Roux-en-Y gastric bypass (RYGB), 15% to 35% of patients fail to lose sufficient weight. Distalization of the limbs of the RYGB (D-RYGB) with shortening of the common channel (CC), has been used to induce additional weight loss. However, this may increase the risk of malnutrition. OBJECTIVE: The aim of this study was to assess postoperative outcomes after D-RYGB with an alimentary limb of 250 to 300 cm and CC of 100 cm. SETTING: General hospital, specialized in bariatric surgery. METHODS: We retrospectively studied all patients who underwent revision of RYGB to D-RYGB between January 2014 and April 2018. Data were collected from medical records, including weight loss, nutritional deficiencies, and co-morbidities. Questionnaires on defecation pattern, quality of life, and patient satisfaction were obtained. RESULTS: Forty-seven patients were included. Total weight loss (%TWL) increased significantly from 12% to 30% after D-RYGB. In 62% of patients %TWL >25% was achieved. Patients with %TWL <25% after primary RYGB, lost significantly more weight than initially reached after RYGB. Diabetes and hypertension remission occurred in 67% and 50%, respectively. Five patients (11%) needed subsequent lengthening of the CC to 250 cm due to protein malnutrition or debilitating defecation patterns. Nutritional deficiencies were present in 89% of patients after D-RYGB despite the prescription of specialized multivitamins. CONCLUSION: Conversion of the primary RYGB to D-RYGB improves weight loss and co-morbidities in patients with insufficient weight loss after primary RYGB. After D-RYGB, nutritional complications and diarrhea are a risk. Based on this study, a modified D-RYGB with a longer CC of >200 cm will be considered.

Face, Content, and Construct Validity of the Take-Home EoSim Augmented Reality Laparoscopy Simulator for Basic Laparoscopic Tasks.

Background: The eoSim® laparoscopic augmented reality (AR) simulator has instrument tracking capabilities that may be suitable for implementation in laparoscopic training. The objective is to assess face, content, and construct validity of this simulator for basic laparoscopic skills training. Methods: Participants were divided into three groups: novices (no training), intermediates (<50 laparoscopic procedures), and experts (>50 laparoscopic procedures). Three basic tasks were completed on the simulator: thread transfer (1), cyst dissection (2), and tube ligation (3). A questionnaire was completed on realism, didactic value, and usability of the simulator. Measured outcome parameters were as follows: time, distance, time off screen, average speed, acceleration, and smoothness. Results: Mean ± standard deviation scores on realism were positive (Task 1 or T1; 3.9 ± 0.7, P = .13, T2; 3.7 ± 0.7, P = .07, T3; 3.7 ± 0.07), as well as didactic value (T1; 3.9 ± 0.8, P = .71, T2; 3.9 ± 0.8, P = .31, T3; 4.0 ± 0.8, P = .40). Usability was valued the highest, with mean scores between 3.9 and 4.3 (T1; P = .71, T2; P = .80, T3; P = .85). Scores did not differ significantly between groups. Experts were significantly faster (Task 1; P < .001, Task 2; P = .042, Task 3: P < .001) with higher handling speed for tasks 2 and 3 (Task 1; P = .20, task 2; P = .034, task 3; P = .049). Results for other outcome parameters also indicated experts had better instrument control and efficiency than novices, although these differences did not reach statistical significance. Conclusions: The eoSim laparoscopic AR simulator is regarded as a realistic, accessible, and useful tool for the training of basic laparoscopic skills, with good face validity. Construct validity of the eoSim AR simulator was demonstrated on several core variables, but not all.

Construct, content and face validity of the eoSim laparoscopic simulator on advanced suturing tasks.

BACKGROUND: The purpose of this study was to validate the eoSim, an affordable and mobile inanimate laparoscopic simulator with instrument tracking capabilities, regarding face, content and construct validity on complex suturing tasks. METHODS: Participants recruited for this study were novices (no laparoscopic experience), target group for this training (surgical/gynaecologic/urologic residents, > 10 basic and < 20 advanced laparoscopic procedures) and experts (> 20 advanced laparoscopic procedures). Each participant performed the intracorporeal suturing exercise (Task 1), an upside down needle transfer (Task 2, developed for this study) and an anastomosis needle transfer (Task 3). Following, the participants completed a questionnaire regarding their demographics and opinion on the eoSim in terms of realism, didactic value and usability. Measured outcome parameters were time, distance, percentage of instrument tip off-screen, working area, speed, acceleration and smoothness. RESULTS: In total, 104 participants completed the study, of which 60 novices, 31 residents and 13 experts. Face and content validity results showed a mean positive opinion on realism (3.9 Task 1, 3.6 Task 2 and 3.7 Task 3), didactic value (4.0, 3.4 and 3.7, respectively) and usability (4.2. 3.7 and 4.0, respectively). There were no significant differences in these outcomes between the specified expertise groups. Construct validity results showed significant differences between experts, target group or novices for Task 1 in terms of time (means 339, 607 and 1224 s, respectively, p < 0.001) and distance (means 8.1, 15.6 and 21.7 m, respectively, p < 0.001). Task 2 showed significant differences between groups regarding time (p < 0.001), distance (p 0.003), off-screen (p < 0.001) and working area (p < 0.001). Task 3 showed significant differences between groups, after subanalyses, on total number of stitches (p < 0.001), time per stitch (p < 0.001) and distance per stitch (p < 0.001). CONCLUSIONS: The results of this study indicate that the eoSim is a potential meaningful and valuable simulator in the training of suturing tasks.

Diagnosing Internal Herniation After Roux-en-Y Gastric Bypass Surgery: Literature Overview, Cadaver Study and the Added Value of 3D CT Angiography.

PURPOSE: The purposes of the study are to outline the complexity of diagnosing internal herniation after Roux-en-Y gastric bypass (RYGB) surgery and to investigate the added value of computed tomography angiography (CTA) for diagnosing internal herniation. MATERIALS AND METHODS: A cadaver study was performed to investigate the manifestations of internal hernias and mesenteric vascularization. Furthermore, a prospective, ethics approved study with retrospective interpretation was conducted. Ten patients, clinically suspected for internal herniation, were prospectively included. After informed consent was obtained, these subjects underwent abdominal CT examination, including additional arterial phase CTA. All subjects underwent diagnostic laparoscopy for suspected internal herniation. The CTA was used to create a 3D reconstruction of the mesenteric arteries and surgical staples (3D CTA). The 3D CTA was interpreted, taking into account the presence and type of internal hernia that was found upon laparoscopy. RESULTS: Cadaveric analysis demonstrated the complexity of internal herniation. It also confirmed the expected changes in vascular structure and surgical staple arrangement in the presence of internal herniation. 3D CTA studies of the subjects with active internal hernias demonstrated remarkable differences when compared to control 3D CTA studies. The blood supply of herniated intestinal limbs in particular showed abnormal trajectories. Additionally, enteroenterostomy staple lines had migrated or altered orientation. CONCLUSION: 3D CTA is a promising technique for diagnosing active internal hernias. Our findings suggest that for diagnosing internal hernias, focus should probably shift from routine abdominal CT examination towards the 3D assessment of the mesenteric vasculature and surgical staples.

Randomized controlled trial of transoral incisionless fundoplication vs. proton pump inhibitors for treatment of gastroesophageal reflux disease.

OBJECTIVES: Transoral incisionless fundoplication (TIF) was developed in an attempt to create a minimally invasive endoscopic procedure that mimics antireflux surgery. The objective of this trial was to evaluate effectiveness of TIF compared with proton pump inhibition in a population consisting of gastroesophageal reflux disease (GERD) patients controlled with proton pump inhibitors (PPIs) who opted for an endoscopic intervention over lifelong drug dependence. METHODS: Patients with chronic GERD were randomized (2:1) for TIF or continuation of PPI therapy. American Society of Anesthesiologists >2, body mass index >35 kg/m(2), hiatal hernia >2 cm, and esophageal motility disorders were exclusion criteria. Primary outcome measure was GERD-related quality of life. Secondary outcome measures were esophageal acid exposure, number of reflux episodes, PPI usage, appearance of the gastroesophageal valve, and healing of reflux esophagitis. Crossover for the PPI group was allowed after 6 months. RESULTS: A total of 60 patients (TIF n=40, PPI n=20, mean body mass index 26 kg/m(2), 37 male) were included. At 6 months, GERD symptoms were more improved in the TIF group compared with the PPI group (P<0.001), with a similar improvement of distal esophageal acid exposure (P=0.228) compared with baseline. The pH normalization for TIF group and PPI group was 50% and 63%, respectively. All patients allocated for PPI treatment opted for crossover. At 12 months, quality of life remained improved after TIF compared with baseline (P<0.05), but no improvement in esophageal acid exposure compared with baseline was found (P=0.171) and normalization of pH was accomplished in only 29% in conjunction with deteriorated valve appearances at endoscopy and resumption of PPIs in 61%. CONCLUSION: Although TIF resulted in an improved GERD-related quality of life and produced a short-term improvement of the antireflux barrier in a selected group of GERD patients, no long-term objective reflux control was achieved.

In vivo assessment of a biological occluder for NOTES gastrotomy closure.

BACKGROUND: The objective of this study is to evaluate the closure of a transgastric natural orifice transluminal endoscopic surgery (NOTES) access using a multilayer extracellular matrix (ECM) occluder in a canine model. MATERIALS AND METHODS: Mongrel dogs (n = 4) underwent a transgastric NOTES peritoneoscopy and the gastrotomy was closed by deploying a 2-sided ECM occluder. Animals were killed at 7 days (n = 2) and 8 weeks (n = 2) for macroscopic and microscopic assessment. RESULTS: All procedures were completed without any complications. No air leaks were detected immediately after the procedure and at 48 hours postoperatively. At 7 days, ECM appeared to be resolved and mild mucosal inflammation was found at the site of gastrotomy. At 8 weeks, the gastrotomy site was macroscopically and microscopically covered with a normal-appearing gastric mucosa. There was an absence of inflammatory cells and no evidence of the ECM. CONCLUSION: The ECM occluder is safe and effective in this "proof-of-concept" preclinical model.

Revisional laparoscopic antireflux surgery after unsuccessful endoscopic fundoplication.

BACKGROUND: Transoral incisionless fundoplication (TIF), a novel endoscopic procedure for treating gastroesophageal reflux disease (GERD), currently is under evaluation. In case of treatment failure, subsequent revisional laparoscopic antireflux surgery (rLARS) may be required. This study aimed to evaluate the feasibility, safety, and outcomes of revisional antireflux surgery after previous endoscopic fundoplication. METHODS: Chronic GERD patients who underwent rLARS after a previous TIF procedure were included in the study. Pre- and postoperative assessment included GERD-related quality-of-life scores, proton pump inhibitor (PPI) usage, 24-h pH-metry, upper gastrointestinal endoscopy, and registration of adverse events. RESULTS: Revisional laparoscopic Nissen fundoplication was feasible for all 15 patients included in the study without conversions to open surgery. Acid exposure of the distal esophagus improved significantly after rLARS, and esophagitis, PPI usage, and hiatal hernia decreased. Quality of life did not improve significantly after rLARS, and 33 % of the patients experienced dysphagia. CONCLUSION: Revisional laparoscopic Nissen fundoplication was feasible and safe after unsuccessful endoscopic fundoplication, resulting in objective reflux control at the cost of a relatively high rate of dysphagia.

Transoral incisionless fundoplication for treatment of gastroesophageal reflux disease in clinical practice.

BACKGROUND: Transoral incisionless fundoplication is a recently introduced endoluminal technique for the treatment of gastroesophageal reflux disease (GERD). The objective of this study was to determine outcomes in chronic GERD patients who were referred for surgical management. METHODS: A cohort of 38 patients underwent transoral incisionless fundoplication (TIF) in a tertiary care setting. Pre- and post-procedure assessment included GERD-related quality of life questionnaires, proton pump inhibitor (PPI) usage, 24-h pH measurements, upper gastrointestinal endoscopy, esophageal manometry, and registration of adverse events. Duration of follow-up was 36 months. RESULTS: Gastroesophageal valves were constructed of 4 cm (range, 4-6) in length and 220° (range, 180-240) in circumference. One serious adverse event occurred, consisting of intraluminal bleeding at a fastener site. Hiatal hernia was completely reduced in 56 % and esophagitis was cured in 47 % of patients. Postprocedure esophageal acid exposure did not significantly improve (p > 0.05). At 36 (range, 29-41) months follow-up 14 patients (36 %) had undergone revisional laparoscopic fundoplication. Quality of life scores of the remaining cohort showed significant improvement (p < 0.0001) and daily use of antisecretory medication was discontinued by 74 %. CONCLUSIONS: Endoluminal fundoplication improved quality of life and reduced the need for PPIs in only a subgroup of patients at 3 years follow-up. The amount of patients requiring additional medication and revisional surgery was high.

The laparoscopic approach to paraesophageal hernia repair.

INTRODUCTION: Laparoscopic paraesophageal hernia repair continues to be one of the most challenging procedures facing the minimally invasive surgeon. DISCUSSION: A thorough understanding of the tenets of the operation and advanced skills in minimally invasive laparoscopy are needed for long-term freedom from symptomatic and anatomic recurrence. These include complete reduction of the hernia sac from the mediastinum back into the abdomen with careful preservation of the integrity of muscle and peritoneal lining of the crura, aggressive and complete mobilization of the esophagus to the level of the inferior pulmonary vein, vagal preservation, clear identification of the gastroesophageal junction to allow accurate assessment of the intraabdominal esophageal length, and use of Collis gastroplasty when esophageal lengthening is required for a tension-free intraabdominal repair. Liberal mobilization of the phrenosplenic and phrenogastric attachments substantially increases the mobility of the left limb of the crura, allowing for a tension-free primary closure in a large percentage of patients. CONCLUSION: The following describes our current approach to laparoscopic paraesophageal hernia repair following a decade of refinement in a high-volume center.

Functional lumen imaging probe to assess geometric changes in the esophagogastric junction following endolumenal fundoplication.

BACKGROUND: The functional lumen imaging probe (FLIP) uses impedance planimetry to measure the geometry of a distensible organ. The purpose of this study was to evaluate FLIP as a method to determine structural changes at the gastroesophageal junction (GEJ) following transoral incisionless fundoplication (TIF) and compare these findings with the accepted methods of esophageal testing. METHODS: Two different approaches (TIF1.0 and 2.0) using the EsophyX™ device were performed in six and five animals, respectively. Three dogs underwent a sham procedure. FLIP measurements were performed pre- and post-procedure and at 2-week follow-up. Upper endoscopy, manometry, and 48-h pH testing were also performed at each time point. FLIP was performed in ten patients before and 3 months after TIF. RESULTS: Following TIF procedures, there was a significant decrease in cross-sectional area (CSA) of GEJ compared to baseline; however, the CSA of both groups returned to baseline at 2-week follow-up. The FLIP results were supported with pH testing and correlated highly with both measures of GEJ structural integrity (LES and cardia circumference). Following TIF in humans, there was a decrease in GEJ distensibility compared to baseline that persisted to the 3-month evaluation. CONCLUSION: FLIP is able to measure and display changes in tissue distensibility at the GEJ, and results correlate with established methods of testing. FLIP may represent a single testing modality by which to diagnose GERD and evaluate the outcome after antireflux surgery.

Transoral endoscopic inner layer esophagectomy: management of high-grade dysplasia and superficial cancer with organ preservation.

INTRODUCTION: Limitations of endoscopic therapies for Barrett's esophagus and superficial cancer include a compromised histological assessment, the need for surveillance, subsequent procedures, and stricture formation. Circumferential en bloc resection of the mucosa-submucosa complex followed by deployment of a biologic scaffold onto the remaining muscularis propria may address these concerns. The objective of this study was to determine technical feasibility of transoral resection of the esophageal lining. MATERIALS AND METHODS: Transoral endoscopic inner layer esophagectomy was performed in ten swine. Endpoints included procedure duration, hemorrhage, number of perforations, and adequacy of resection length and depth. RESULTS: Procedures were successfully completed in all animals without perioperative mortality. Procedure times averaged 179 min (range 125-320). No perforations were found, and a mean of 1.7 (0-4) interventions for hemorrhage was required. Complete longitudinal resection was achieved in nine of ten animals. Resection depth included all mucosal layers in 100% of tissue sections, the submucosal layers, SM1 in 100%, and SM2 in 96%. A portion of SM3 was adherent to the muscularis propria in 70%. CONCLUSION: Transoral endoscopic resection of the inner esophageal layers was feasible and reproducible. This technique may facilitate a single-step definitive treatment and staging tool for early neoplastic lesions, obviating the need for esophagectomy.

Endoscopic therapies for the treatment of reflux disease.

Endoscopic techniques for the treatment of reflux disease were first introduced in 2000 as an alternative to laparoscopic antireflux operations. Because of reports of long-term treatment failure with laparoscopic fundoplication and the fact that surgery is increasingly being reserved for the relatively small proportion of patients with complicated reflux disease, attempts to develop safe, effective, and durable endoscopic approaches to antireflux surgery continue. Techniques include radiofrequency ablation, injection therapy, and suturing/stapling techniques. Of these, the suturing/stapling techniques are most similar to the anatomic restructuring of the gastroesophageal junction provided by fundoplication. While early attempts at endoscopic suturing have been disappointing, significant advances in endoscopic instrumentation, a more complete understanding of the gastroesophageal junction anatomy, and improvements in the technical skills of the endoscopic surgeon have been realized. As a result, techniques now being tested, such as the endoluminal fundoplication, may prove more effective and durable than previous endoscopic antireflux procedures.