The
number of complications following keyhole surgery can be reduced by
giving the surgeons a better feeling of how hard they are grasping the
tissue with their operating instruments. This is made possible by
designing the instrument in such a way that it sends tangible feedback
signals to the handle held by the surgeon. Delft University of
Technology researcher Eleonora Westebring-van der Putten has developed a
working prototype for this.
Keyhole
surgery has rapidly gained in popularity in hospitals. An exploratory
operation – known as a laparoscopy when carried out in the abdominal
cavity – is generally less invasive for the patient. But a laparoscopy
calls for different manual skills than ‘ordinary’ open surgery. Training
in these skills is therefore essential for the prevention of
complications.
Problems
with keyhole surgery partly arise because it is very difficult to gauge
the force of the surgeon’s grasp. The surgeon is therefore less able to
determine whether he or she is grasping the tissue too hard or too
gently.
Industrial
designer and human movement scientist Eleonora Westebring-van der
Putten’s research is focused on the improvement of grasp control and the
learning of the associated skills. The solution is to give the surgeon
tangible physical feedback through his or her instrument.
“Experiments
have shown that augmented feedback on the grasp force is a good way for
surgeons of all levels to gain a better command of gauging laparoscopic
grasp force,” says Westebring.
She
has therefore developed a working prototype of a laparoscopic grasp
instrument that gives augmented tangible feedback on the amount of grasp
force being applied. This prototype therefore gives the surgeon the
required tangible feedback.
“There
are sensors in the tip of the instrument that measure how hard the
surgeon is grasping. This information is fed back to the handle, which
contains a cylinder that can turn in relation to the hand, as if
something is falling out of your hand. In this way the cylinder
indicates that the surgeon has too little grip, and is therefore
grasping too gently,” she says.
“The
handle also contains vibrating elements, which start to vibrate if the
surgeon is grasping too hard, while also taking account of how hard the
surgeon is pulling. The harder he or she pulls on the tissue, the less
hard he or she should grasp. We also take the type of tissue into
account. After all, it makes quite a difference whether you are grasping
an intestine or working with a liver,” she says.
In the future an instrument such as Westebring’s could be used in training for real operations.
“By
training with feedback, surgeons learn to control their laparoscopic
grasp force more quickly. The forces they apply are lower,” she says.
What is more, the effect seems to last. “When the feedback signal is
removed, the surgeons can still carry out the procedure with reduced
force. The feedback therefore helps with the control of the laparoscopic
grasp force, even if it is only used in training.”
