Search

Sentinel node biopsy is proposed as sufficiently reliable in determining the lymph node status of early gastric cancer to justify curtailed resection margins if negative. Its performance by natural orifice transluminal endoscopic surgery (NOTES) could therefore expand the patient cohort able to undergo solely endoscopic resection of their primary. A transvaginal NOTES technique was utilized in six pigs (mean weight 30 kg). The posterior colpotomy and pneumoperitoneum was created by a standard double-channel flexible videoendoscope which was then used to perform peritoneoscopy. Concomitant gastroscopy allowed selection of a site along the greater curvature for lymphatic mapping by submucosal injection of methylene blue (3 ml). Furthermore, torque upon this endoscope allowed the posterior surface of the stomach and retrogastric space to become accessible to the transvaginal endoscope. In surveying the mapping in vivo, the intraperitoneal scope could follow blue-stained efferent lymphatic channels to their first-order draining nodes (i.e., sentinel nodes). Conventional instruments worked down the scope’s channels were then used to perform the excisional biopsy. At procedure end, the animals underwent immediate laparotomy to ensure the safety and adequacy of the procedure. Each procedure was technically successful. Colpotomy, pneumoperitoneum, and peritoneoscopy were promptly achieved (mean 8 min). Post injection, blue efferent lymphatic channels were immediately appreciable in every animal. Five animals had sentinel nodes in their retropyloric region while the last mapped cephalad towards the esophagogastric junction. Two animals had alternative drainage channels identifying additional sentinel nodes. All blue nodes were dissected cleanly by the intraperitoneal scope and retrieved intact per vaginam. Mean lymphadenectomy time was 19 min. At laparotomy, there was no hematoma, ongoing hemorrhage, or visceral injury in any pig. There were no residual, missed stained nodes or channels. NOTES sentinel node biopsy for the stomach is technically accomplishable in this experimental model. This proof of concept should encourage serious consideration of its applicability to clinical practice. [ABSTRACT FROM AUTHOR]

Background: Several working groups have already demonstrated the feasibility of transgastric surgery procedures using flexible endoscopes. However, technical limitations in natural orifice translumenal endoscopic surgery (NOTES) (e.g., exposure, retraction, insufflations, and triangulation) currently still require the use of at least one external instrument. Therefore, "pure NOTES" transgastric cholecystectomy has not yet been described. The authors successfully performed "pure NOTES" transgastric cholecystectomy using a transoral dual-scope technique (similar to the approach the authors previously reported for gastric closure) that allows completion of the procedure by pure NOTES without an external instrument.Methods: With the subject under general anesthesia, a double-channel gastroscope (Storz®, Tuttlingen, Germany) passed by mouth entered the peritoneum through the distal anterior gastric wall. The most ideal site for a second gastric exit was then selected for another single-channel scope. With the gallbladder retracted by the assistant operating the double-channel scope, retrograde cholecystectomy was performed by the primary surgeon using the single-channel scope. Four animals were killed immediately to study the quality of the operative dissection, whereas the other four pigs were kept alive. The gastrotomy was closed using a 27- to 30-mm cardiac septal occluder (Occlutech®, GmbH, Jena, Germany) according to a previously described method. The postoperative follow-up assessment of these animals included laparoscopy and necropsy 2 weeks later.Results: All the cholecystectomies were immediately successful without any intraoperative complication. Scope withdrawal caused no injuries to the esophagus or pharynx. Although no overt postoperative complication was evident, two surviving pigs had signs of minor peritoneal infection.Conclusions: This study investigated "pure NOTES" transgastric cholecystectomy using tentative experimentation to overcome the "retraction" and "triangulation" issues and to realize a "pure NOTES" operation. The use of two endoscopes with selected differentiation of their gastric placements compensated for the lack of triangulation and retraction. [ABSTRACT FROM AUTHOR]