  Under conventional "open-" surgery, the physician has to take care of the
patient, interact with other clinicians and check several monitoring devices.
Nowadays, the Computer Assisted Surgery proposes to integrate 3D cameras in the
operating theatre in order to assist the surgeon in performing minimal-invasive
surgical punctures. The cameras localize the needle and the computer guides the
surgeon towards an intracorporeal clinically-defined target. A visualization
system (screen) is employed to provide the surgeon with indirect visual spatial
information about the intracorporeal positions of the needle. The present work
proposes to use another sensory modality to guide the surgeon thus keeping the
visual modality fully dedicated to the surgical gesture. For this, the sensory
substitution paradigm using the Bach-y-Rita's "Tongue Display Unit" (TDU) is
exploited to provide to the surgeon information of the position tool. The TDU
device is composed of a 6x6 matrix of electrodes transmitting electrotactile
information on the tongue surface. The underlying idea consists in transmitting
information about the deviation of the needle movement with regard to a
pre-planned "optimal" trajectory.
