Magnetic Trackers: Robot Control and Vasculature Imaging - Microsurgery: Advances, Simulations, and Applications - page 237

7.4 Robot Guidance
In order to reduce the use of the luoroscope in endovascular surgery,
there is a need to develop autonomous catheter insertion systems. In
this section, we show the catheter motion capture with a magnetic
tracker for providing feedback control to a catheter insertion robot.
With that feedback, autonomous catheter insertion in silicone
models of major vasculature can be achieved as preliminary step for
in vivo experiments.
Magnetic tracker probes are 0.8 mm × 8 mm diameter and length,
respectively, and they have been used in medical instrumentation
tracking projects, as needle guidance [2], bronchoscope navigation
[3] and navigation in laparoscopic surgery [4]. Different calibration
methods for them using mathematical methods have been compared
by Kindratenko [5]. Others using optical trackers for a co-calibration
between sensors are proposed by [3, 6, 7]. Here, we navigate
catheter in major vasculature models by applying the methodology
shown at the beginning of this chapter. For catheter driving devices
for telesurgery such as [8-11]; feedback of the catheter motion is
provided by encoders or accelerometers placed on the joints of
the driving mechanism. For those cases, it is not possible to track
accurately the catheter tip position inside a membranous structure,
such as blood vessels or silicone models, because catheter is not
a rigid body and its shape changes according to the blood vessel
wall shape and deformation. In this study an Autonomous Catheter
Insertion System (ACIS) was evaluated using micro coils placed on
the catheter tip for motion capture and feedback accurately the
position and speed to the catheter insertion robot LSM. Then with
that information and a sparse LUT as reference, catheter insertion
path reconstruction was developed.
Controlling the speed of the catheter tip allows detection of
catheter trapping, with that vascular membrane puncture could be
avoided. An ACIS should be able to reproduce a predeined insertion
path to reach a target and to control catheter speed to avoid
puncturing the organ membrane.
7.4.1 Evaluation Field
The ACIS was evaluated for path reconstruction and speed control
during a catheter surgery simulation inside silicone models major