Gastric surgery and notes

Development and testing of a grasper for NOTES powered by variable stiffness pneumatic actuation

BACKGROUND

In natural orifice transluminal endoscopic surgery (NOTES) the peritoneal cavity is reached through natural orifices (mouth, rectus and transvaginal duct), by means of little cuttings in the walls of hollow organs. Due to narrow spaces, NOTES needs robotic systems to assure operation/movement precision and patient safety. Variable stiffness actuation (VSA) assures both requirements.

METHODS

The authors developed a grasper for NOTES, provided with VSA, to use as an end-effector for snail robot devices. The present paper deals with basic concepts of VSA and describes the design and architecture of the grasper. Characterization and functional experiments were performed and results analysed.

RESULTS

A finite element model developed for the actuator design was validated, performance grasper characteristic curves were obtained, VSA was validated, and the gripping capability of several objects was assessed.

CONCLUSION

The grasper satisfies technical design specifications. On the basis of the results obtained, a control system can be developed to test grasper in a simulated surgery environment.

Hybrid NOTES: Combined Laparo-endoscopic Full-thickness Resection Techniques

Advances in laparoscopic surgery and therapeutic endoscopy have allowed these minimally destructive procedures to challenge conventional surgery. Because of its theoretic advantages and technical feasibility, laparoendoscopic full-thickness resection is considered to be the most appropriate option for subepithelial tumor removal. Furthermore, combination of laparoscopic and endoscopic approaches for treatment of neoplasia can be important maneuvers for gastric cancer resection without contamination of the peritoneal cavity if the sentinel lymph node concept is established. We are certain that the use of laparoendoscopic full-thickness resection will provide valuable experience that will allow operators to safely develop endoscopic full-thickness resection skills.