Access systems and methods of intra-abdominal surgery

A method of intra-abdominal surgery, comprising:

• a) inserting a distal end of a natural orifice transluminal endoscopic surgery (NOTES) access system into a hole in an anatomic wall, the access system having an overtube with a distal end;
• b) securing the access system to the anatomic wall at the hole;
• c) inserting a flexible port through the overtube of the access system, the port having a shaped portion at the distal end of the overtube;
• d) inserting a flexible endoscope through the port;
• e) using the shaped portion of the flexible port to direct the flexible endoscope along a determined trajectory, the endoscope extending through the port;
• f) inserting a flexible tunneling instrument through the port and longitudinally expanding a distal end of the tunneling instrument to form a tunnel at an interface between first and second tissues;
• and
• g) inserting a dissecting instrument into the tunnel and radially expanding the dissecting instrument within the tunnel at the interface between first and second tissues to cause dissection of the first and second tissues from each other.