A novel magnetic-driven tissue retraction device for minimally invasive surgery.
BACKGROUND
The purpose of this work is to design and validate an innovative magnetic-based device for tissue retraction for minimally invasive surgery.


METHODS
An intra-abdominal magnetic module is coupled with an extracorporeal system for establishing a stable attraction, and consequently a reliable tissue retraction. Once the retractor has been inserted into the abdomen, tissue retraction is not constrained by a fixed access port, thus guaranteeing a more flexible, safer and less invasive operation. The intra-abdominal unit is composed of an axial permanent magnet attached to a stainless-steel non-magnetic alligator clip by a traditional suturing thread. A miniaturized mechanism to adjust the length of the suturing thread for lengthening or shortening the distance between the tissue grasper and the internal magnetic unit is included. A multiphysics approach assured a dedicated design that thoroughly fulfills anatomical, physiological and engineering constraints.


RESULTS
System functionalities were demonstrated both in in-vitro and ex-vivo conditions, reaching good results and promising outcomes in terms of effectiveness and maneuverability. The retractor was successfully tested in an animal model, carrying out a whole retraction procedure.


CONCLUSIONS
The proposed retraction system resulted to be intuitive, reliable, robust and easy to use, representing a suitable device for MIS procedures.
a Scuola Superiore Sant'Anna , The BioRobotics Institute , Pontedera , Pisa , Italy.
Margherita
M
Brancadoro
a Scuola Superiore Sant'Anna , The BioRobotics Institute , Pontedera , Pisa , Italy.
Selene
S
Tognarelli
a Scuola Superiore Sant'Anna , The BioRobotics Institute , Pontedera , Pisa , Italy.
Gastone
G
Ciuti
a Scuola Superiore Sant'Anna , The BioRobotics Institute , Pontedera , Pisa , Italy.
Arianna
A
Menciassi
D000818:Animals; D003198:Computer Simulation; D004867:Equipment Design; D005260:Female; D008280:Magnetics; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation*; D013552:Swine
FEM simulation; MIS; Magnetic surgical device; retraction; surgical tool