The mobility of soft tissue can cause inaccurate needle insertions. Particularly in steering applications that employ thin and flexible needles, l arge deviations
can occur between preoperative images of the patient, from which a procedure is planned, and the intraoperative scene, where a procedure is executed.
Whereas many approaches for reducing tissue motion focus on external constraining or manipulation, little attention has been paid to the way the needle is inserted and actuated within soft tissue.
Using our
biologically inspired
steerable needle, we present a
metho
d
of reducing the
disruptiveness
of
insertion
s
by mimicking the burrowing mechanism of ovipositing wasps. Internal
displacements and strains
in three dimensions
within a soft tissue phantom are measured
at
the needle interface
,
using a
scanning
laser
based
image correlation technique.
Compared
to a conventional insertion method
with an equally sized needle
,
overall displacements
and
strains
in the needle vicinit
y
are
reduced by 30% and 41
%, respectively
.
The results show
that
, for a given net speed,
needle
insertion
can be
made
significantly less disruptive
with
respect
to its surroundings by
employing our biologically inspired solution
.
This will have
significant impact on both the safety and targeting accuracy of percutaneous interventions
along both strai
ght and curved trajectories