Peter Koehler

Comparative study of NOTES alone vs. EUS-guided NOTES procedures

BACKGROUND AND STUDY AIMS Natural-orifice transluminal endoscopic surgery (NOTES) is in the developmental stage for various indications, but several obstacles remain to be overcome before NOTES procedures can come into routine clinical use. Of these obstacles, (1) transluminal injury due to exclusive use of endoluminal endoscopy to create the incision and (2) lack of orientation might be prevented by employing endoscopic ultrasound guidance. In this comparative study we assessed the role of endoscopic ultrasound guidance in various NOTES procedures. METHODS Three transesophageal (mediastinoscopy/thoracoscopy) or transgastric procedures (gastrojejunostomy, adrenal gland removal) were performed in pigs using NOTES alone or with endoscopic ultrasound guidance (EUS). In NOTES alone the study end point was three major complications, at which point EUS guidance was added for the same procedures up to the same number of cases. The primary outcome was the rate of major complications; secondary outcome parameters were all complications and technical success. RESULTS Forty-six pigs were included. Three major complications occurred in the first 24 NOTES-alone procedures: these were bleeding and organ injury, all during mediastinoscopy/thoracoscopy procedures. Adrenal gland removal failed in all procedures in which it was attempted, while gastrojejunostomy (n = 6) was performed successfully and without complications. In the next 22 animals EUS guidance enabled safe mediastinal access (n = 10) and adrenal gland removal (n = 6). For gastrojejunostomy, EUS guidance offered no additional benefit. CONCLUSIONS EUS guidance appears to be helpful in gaining access or identifying structures in anatomically difficult areas in NOTES procedures.

Feasibility and safety of endoscopic full-thickness esophageal wall resection and defect closure: a prospective long-term survival animal study

BACKGROUND The first experiences with endoscopic closure of esophageal perforations in animal survival studies encouraged us to extend these procedures to full-thickness resections of pieces of the esophageal wall (FTEW). OBJECTIVE To learn the feasibility, safety, and long-term effects of FTEW removal and defect closure. DESIGN Feasibility animal study. SETTING Approved animal facility. INTERVENTIONS Twelve pigs were used for 3-month survival studies, autopsy, and histologic examination. Resection of a 2-cm piece of wall was performed with needle-knife and forceps/snare. Closure was performed by using prototype endoscopic suturing. MAIN OUTCOME MEASUREMENTS Feasibility and complication assessment of this new endoscopic method. RESULTS There were no complications relating to incision, resection, or closure. All pigs recovered quickly. In 2 animals a larger piece of wall causing a larger defect was removed, resulting in much air penetrating into the mediastinum, causing difficult ventilation. This was resolved with thoracic drain. In 3 of 12 animals a toxic substance slipped into the mediastinum, resulting in an abscess in 1 pig and misfire of an anchor as a result of obscured vision. This caused temporary illness of the animal but not death. Autopsy and histologic study confirmed no mediastinitis and well-healed scars in all but one. LIMITATION Animal study. CONCLUSION FTEW has proven to be feasible. Long-term survival demonstrated no mediastinitis and only 1 abscess after contamination of the mediastinum. These first experiences encourage further animal studies because the prospect of endoscopic full-thickness removal of esophageal lesions in patients might be very advantageous.

Transplantation of Mucosa From Stomach to Esophagus to Prevent Stricture After Circumferential Endoscopic Submucosal Dissection of Early Squamous Cell

Strasbourg University Hopitals-Nouvel Hôpital Civil and IHU, Strasbourg, France; Department of Medicine III Gastroenterology, St. Bernward-Hospital, Hildesheim, Germany; Friedrich Loeffler Federal Research Institute of Farm Animal Genetics (FLI) Mariensee, Germany; Department of Pediatric Surgery, St. Bernward-Hospital, Hildesheim, Germany; Darmouth Medical College, Hanover, New Hampshire; Rebirth DFG-Cluster of Excellence, Leibnitz Research Laboratories for Biotechnology and Artificial Organs, Hannover Medical School, Hannover, Germany; and Division of Gastroenterology, Mount Sinai School of Medicine, New York, New York