| March 13, 2001
Robot-Assisted Brain Surgery
Is Feasible Says Penn Researcher Surgical System Designed
for Space Is Practical for Earthbound Use
(Philadelphia, PA) - Despite
advances in technology and technique, there will always
be one limiting factor in the operating room: the surgeon.
Hours of exacting work can tire anybody, especially
someone navigating the delicate intricacies of the human
The solution is as old as science fiction, but the
technology has only recently caught up to the concept.
The Robot-Assisted Microsurgery (RAMS) prototype is
a robotic surgical tool first developed for space use
and later refined as a precision instrument for microsurgery.
Peter D. LeRoux, MD, a neurosurgeon at the University
of Pennsylvania Medical Center, reports on the feasibility
of RAMS in brain surgery in the March issue of Neurosurgery.
"The RAMS system works like an extension of the surgeon's
hands," said LeRoux. In essence, the system consists
of a set of robotic arms: a master arm, which functions
like a joystick; and an operating arm, which actually
performs the surgery. The surgeon manipulates the master
arm just as they would hold a surgical instrument, and
the operating arms mimic the surgeon's movements on
the patient. "Robotic surgery is not about replacing
surgeons, but enhancing their abilities in the operating
room," explained LeRoux.
The concept is simple, RAMS serves as an intermediary
between the surgeon's hands and the surgical instruments.
In effect, it allows the surgeon to filter out the slight
tremors that are present in even the most skilled surgical
hands. The advantage of a robotic surgical system is
that it could remove some of the random factors that
affect surgery. "A surgeon's performance can vary throughout
a lifetime - or even during a procedure," explained
LeRoux. "Automation can compensate for these variables
and lead to better results for patients."
According to LeRoux, RAMS also represents a change
in the way surgical tools are created. Typically, surgeons
are the ones who recognize the need of a particular
tool, and then call upon the expertise of engineers
to develop it. Here, however, the engineers developed
the surgical tool to solve a particular problem. At
the behest of NASA, the Jet Propulsion Laboratory first
developed the RAMS prototype as a means of conducting
emergency surgery via remote control. They envisioned,
for example, surgeons on earth performing robotic surgery
on an astronaut in space.
The limitations of remote controlled surgery are obvious,
since the further the surgeon is from the patient, the
longer the signal takes to get between the two. "It
gets to a point when a 'real-time' operation just couldn't
work in real time," said LeRoux.
Long distance surgery is not the only application of
the technology. With the help of MicroDexterity Systems,
Inc., JPL further developed the system to assist microsurgery.
LeRoux and his colleagues were granted use of RAMS to
see how well the system would apply to the demands of
precise surgical operations. The researchers first experimented
with the technology in trials with nonanimal models,
getting a feel for the controls while they practiced
their techniques. Impressed with their results, they
began trials in 10 rats, repairing blood vessels that
supply the brain, a common microsurgical procedure.
Although the procedures using RAMS took longer than
average - which LeRoux attributes in part to the learning
curve - the researchers were able to demonstrate that
the concept was sound.
Still, RAMS is not perfect, and the system would need
further development for it to be useful in human surgery.
LeRoux notes the lack of tactile feedback - the sense
that your hands are pushing against real objects - and
the limited degrees of freedom the prototype robot hand
has in comparison with that of a human hand. However,
the researchers remain optimistic that engineers can
overcome many of the technical hurdles with the help
of feedback from surgeons. "In many ways, this technology
is just a crude prologue to some of the amazing things
that are ahead," said LeRoux. "There is clearly a lot
of work to be done, but the potential is enormous."
LeRoux comes to Penn's Department of Neurosurgery as
an Associate Professor after working at the New York
University Medical Center, during which time he began
his work with RAMS. He is a Fellow of the American College
of Surgeons and has previously won the prestigious World
Federation of Neurosurgical Societies Young Neurosurgeon
Award. His research is funded by the National Institutes
The University of Pennsylvania Health System is distinguished
not only by its historical significance - first hospital
(1751), first medical school (1765), first university
teaching hospital (1874), first fully integrated academic
health system (1993) - but by its position as a major
player on the world stage of medicine in the 21st century.
Penn ranks second among all American medical schools
that receive funds from the National Institutes of Health,
perhaps the single most important barometer of research
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