Safe sigmoid access for natural orifice transluminal endoscopic surgery (NOTES).

One of the main challenges in transluminal surgery is sterile and safe access. For many interventions, a transanal approach would be ideal but it is considered too risky because of contamination and the danger of secondary leakage. A new safe and sterile transanal access was developed, combining four basic principles: (i) the creation of a decontaminating hydroperitoneum, (ii) the use of an overtube, (iii) defining the entry point with ultrasound and (iv) dedicated closure technique. Applicability and reliability was first proven in extensive animal experiments. Feasibility of the concept in humans was subsequently demonstrated in cadavers.