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Perry Newhook never expected his career as a robotics engineer would lead him to an operating room where open brain surgery was being performed.
Yet that’s where Burlington, Ont.-based MDA Corp.’s project leader on the neuroArm started to understand a unique client.
The University of Calgary neurosurgery team had given Newhook a concise, yet wide-open directive: “We want a robot that does what we do, but better.”
“I’d never seen a surgery before – not many of us had,” Newhook recalls of his team’s visit out West. “You’re seeing a person with their brain exposed.”
From that point, it was a lot of work to create the human-sized, two-armed robot that required more than $30 million to develop.
Newhook’s team has worked hand in hand with award-winning neurosurgeon Dr. Garnette Sutherland and his team at the university since 2002. Dr. Sutherland is often called upon by academic medical centres to perform difficult brain aneurysm surgeries that no other surgeon will do.
Image courtesy University of Calgary.
Now after creating a robot that can operate with sub-millimeter accuracy and is the most complex robot to ever operate inside a magnetic resonance imaging (MRI) scanner, the team has completed a test phase that involved operations on cadavers and lab rats.
If the neuroArm team gets the ethical clearance hoped for on Thursday, all hurdles will be finally be cleared for its use in a standard operating room.
“Ethics clearance is the last remaining hoop,” Sutherland says. “We began this process over two years ago.”
NeuroArm is about three feet tall and two feet wide, and weighs about 500 lbs.
Its two arms are the bulk of the robot, and each operates with seven degrees of freedom – or as if each arm had seven double-jointed elbows, according to the projects’ Web site.
It’s not constructed of metal like most robots, but instead out of titanium and a complex plastic compound known as PEEK. MDA had to construct a robot that could operate inside an MRI machine, meaning it couldn’t result in any magnetic interference.
Dr. Sutherland had previously developed the world’s first intra-operative MRI machine with Winnipeg-based robotics maker IMRIS Inc. Constructing neuroArm in this way was the project’s biggest challenge, Newhook says.
“It’s not just your run of the mill robot,” he says. “As soon as you change the materials used, there’s a bit of a learning curve.”
The team had to get several parts custom-made, including ceramic ultrasound motors to help move the arms, and titanium encoders that measure the arm’s spatial orientation.
The advantage of having an MRI scan during an operation is a surgeon can see if an action they’ve taken has had a positive or negative effect on the patient, Sutherland explains.
The images are available on two interactive touchscreens available as part of the high-tech work station a surgeon uses to manipulate the robot.
With two video monitors displaying an overview of the surgical arena and a microscopic view of the task at hand, a computer schematic of the robot’s manipulators, and two joystick-style controllers, it looks more like the ultimate gaming rig than a surgeon’s tool.
In fact, one study compared practiced surgeons to gamers in use of the test controllers, and the gamers proved more skilled, Sutherland says.
“They blew the surgeons out of the water,” he says. “The good news is that surgeons learn fast.”
Even if they’re not perfect, a tremor filter will remove any shaking in a surgeon’s hands when accuracy is called for.
That’s just one of the advantages doctors enjoy from being connected with the “sensory rich” control environment despite being separated from the actual operating room by a see-through divider, Sutherland says.
Surgeons are provided true depth-perception of the surgical site thanks to two hi-definition cameras positioned at the end of each robotic arm.
Scientists looking through a microscope viewer at the workstation can view the stereoscopic output.
Speakers surrounding the surgeon link them to communications with operating team members and the atmospheric sound in the operating room.
Surgeons rely on each of their senses when at work, and each must be replicated, explains the neuroArm project founder.
“Some tumours are very soft and if you have your sucker on them, you can hear them going up the sucker,” he says. “If your sucker went on to the brain, it would be a different pitch and you’d move your sucker away.”
Like sound, a sense of touch is also crucial to performing brain surgery – the slightest movement can make all the difference.
“When you’re dissecting soft objects like the brain, you really want to know you’re on t, because it would be easy to cut through the brain,” Sutherland says.
Image courtesy University of Calgary.
To develop the sense of touch just right, MDA reached out to the neuroArm’s robotic cousin, Dextre. It travelled to the International Space Station last month aboard the Space Shuttle Endeavour.
A mega-sized version of the neuroArm, MDA developed Dextre to install components on the orbital outpost with the same dexterity as a human space walker. From this, Newhook’s team was able to learn the right way to deliver force feedback.
“Dextre has a sense of touch and that’s exactly what we wanted to bring back to the neuroArm,” Newhook says. “The principles are the same: two arms with a sense of touch.”
MDA’s experience developing Dextre was invaluable in creating neuroArm, he adds. “Trying to do a project this complex without a starting point would be very difficult.”
The operating robot also stole a page out of Dextre’s book with the multi-tool located at the end of each arm.
The end-effectors can hold a variety of surgical tools and the robot can even be programmed to exchange tools automatically. It can also move with 30 micron accuracy (one thousand microns make up a millimeter).
NeuroArm proved its accuracy during the pre-clinical experiments conducted over the last year – a phase that included one operation on a living human. But many test operations were also conducted on cadavers.
“We tested whether or not the arm could be placed in a precise target in the brain,” Sutherland says, recalling the experiments. “NeuroArm does a wonderful job of this, every time.”
Next up was the required testing of the robot on live lab rats – with the robot being used to remove organs from the rat’s tiny body.
“The beauty of working on a rat is that they’re small,” the doctor says. “You might think of taking out a kidney from a rat as being like taking about a brain tumour from a human.”
Video courtesy University of Calgary’s neuroArm team.
On Valentine’s Day, neuroArm was used in the same operating room as a live patient for the first time. But no actual surgery was performed by the robot, it was a test-run to practice the procedure of properly dressing the robot and performing a surgery with it in the operating space, Sutherland explains.
If the Calgary team gets their approval this week, they’ll move quickly to put the robot to use in real surgery.
Sutherland has also generated interested in the technology after talking about it at medical conferences and by sending out pamphlets. He hopes to capitalize on that interest with a commercial venture.
“If you build it just for Calgary, it doesn’t help the global community of neurosurgery patients,” he says.
A team of Calgary business people have helped the university with an advising committee and a number of patents have been filed to protect the project’s intellectual property. Eventually a manufacturer for the product will be found, Sutherland says.
“One of our philosophies is to try and keep things Canadian,” he adds. “We want to try and align with a Canadian company to make all of this happen.”
For now, MDA is in discussions with the Calgary team to continue advancement of the neuroArm concept and create a next-generation prototype, Newhook reveals.
That might just mean the engineer will be traveling back out West – to watch more open brain surgery.
