Robot uses real-time MR to boost surgical precision

Dr. Garnette Sutherland with MR-compatible robot developed at the University of Calgary. The robot, called neuroArm, promises to boost a surgeon's precision from millimeters to within 50 microns. Its first patient is scheduled for summer 2007. (Provided by University of Calgary)

An MR-compatible robot debuted April 17 at the University of Calgary/Calgary Health Region amid claims by its developers that this distinctly nonanthropmorphic creation has the power to liberate surgeons "from the constraints of the human hand."

NeuroArm, as the robot is called, will add an unprecedented level of precision and control, according to its creator, Dr. Garnette Sutherland, a professor of neurosurgery at the University of Calgary. And none too soon.

"Many of our microsurgical techniques evolved in the 1960s and have pushed surgeons to the limits of their precision, accuracy, dexterity, and stamina," Sutherland said. "NeuroArm shifts surgery from the organ toward the cellular level."

Surgical and engineering teams are putting the robot through its paces in preparation for surgery on a patient, currently planned for summer.

Surgical planning will be assisted by MR images of the patient, obtained using the university's ceiling-suspended 1.5T scanner. These images, assembled into a model of the patient's brain, will be combined during the procedure with high-definition optical images of the operative field. Together they will create a virtual image of the robot and its instruments operating in real-time.

This virtual reality will be viewed by the surgeon through binoculars like those on a surgical microscope. Hand controllers designed to guide the surgical instruments into and around the brain include an advanced feedback system that will provide the surgeon with a sense of touch.

Tests so far have found that neuroArm allows its operator to place a surgical tool within 50 microns of the intended point. Without such help, surgeons can achieve accuracy between 1 and 2 mm, Sutherland said.

The university framed the debut of neuroArm as a historic moment, praising the system as one of the most advanced robotic systems ever developed. It was designed and built in collaboration with MDA Robotics of Brampton, Ontario, the Canadian firm that made the Space Shuttle's robotic arms. The company worked on neuroArm with international collaborators including health professionals, physicists, and electrical, software, optical, and mechanical engineers. Development began in 2001, when University of Calgary philanthropists provided $2 million as seed money. Other private funds were later supplemented by government financing.

Sutherland said the MR robot is just the first stage in an ambitious plan hatched by the university.

"We're not just building a robot, we're building a medical robotics program," he said.