Endoskopie heute 2008; 21 - FV126
DOI: 10.1055/s-2008-1061247

Evaluation of different transgastric access techniques for NOTES

S von Delius 1, S Gillen 1, E Doundoulakis 1, A Schneider 1, D Wilhelm 1, RM Schmid 1, H Feussner 1, A Meining 1
  • 1Klinikum rechts der Isar der Technischen Universität München

Background: NOTES (natural orifice transluminal endoscopic surgery) is an area of active research in experimental endoscopy and has the potential to significantly advance the field of minimally invasive surgery. Several transgastric access techniques have been described to date. The aim of the current ex-vivo, experimental study was to evaluate different methods of transluminal access with regard to safe closure and leakage after the procedure.

Methods: By using ex vivo porcine stomachs mounted on a custom-made board, the following endoscopic techniques for transgastric access were evaluated. The first arm used standard gastrotomy by needle knife incision; the second, a small gastrotomy and dilation with a controlled radial expansion (CRE) balloon. In the third arm a short (4cm) submucosal tunnel was created by physically separating the mucosa from the muscularis. After the tract was initiated, the scope was advanced within its lumen and a needle knife was used to incise the seromuscular layer at the distal end of the submucosal tunnel. The fourth arm also used a submucosal tunnel, but with an extended tract (8cm). In the interventional arms each mucosal incision was closed with endoscopic clips. Finally, hand-sewn gastric closure by a senior surgeon after needle knife incision served as positive control. Negative controls were stomachs in which the needle knife gastrotomy was not closed. Two stomachs were tested per study arm. After closure, each stomach was inflated with methylen blue stained water by an automated pressure gauge. The pressures to liquid leakage were recorded.

Results: The unclosed controls demonstrated liquid leakage at 1 and 2mmHg, representing baseline system resistance. The hand-sewn gastric closure by a senior surgeon after needle knife incision leaked at 39 and 45mmHg, respectively. The needle knife gastrotomy, the small gastrotomy followed by CRE balloon dilation, the short submucosal tunnel and the extended submucosal tunnel leaked at 23 and 34mmHg, 24 and 27mmHg, 34 an 39.5mmHg, and 67 and 69mmHg, respectively.

Conclusions: The extended submucosal tunnel yielded the best leak-resistance that is superior to standard transgastric access methods and rival hand-sewn interrupted stitches.

Keywords: NOTES, transgastric surgery, transgastric access, leakage