(Vanderbilt University associate professor of mechanical engineering Robert Webster developed the steerable needle system that is being used in the robotic brain surgery device. Courtesy David Comber/Vanderbilt University.)
Robotic Brain Surgeon Takes First Steps
Mechanical engineers working to improve brain surgery for treating epilepsy have unveiled a machine that sounds like it came from a sci-fi movie. At a recent conference, Vanderbilt University researchers presented a pneumatic robot that is designed to drill through a patient’s cheek, guide a steerable needle to the base of the brain, and then destroy malfunctioning tissue causing the disorder.
Their device, made of 3-D printed plastic pieces and a shape-memory alloy steerable needle, can operate inside a working MRI machine to let doctors monitor progress millimeter by millimeter. Their needle is composed of a mixture of nickel and titanium, which isn’t affected by the MRI’s powerful magnetic fields.
The problem the team is trying to address is that a majority of epileptic seizures occur in the hippocampus, an area near the base of the brain. While surgeons now probe for the source of epileptic seizures through the cheek of a patient, current treatments to fix the problem involve going in through the top of the skull with straight needles. This means that doctors must traverse other delicate structures of the brain and travel farther than if they could enter the skull through the cheek.
“The systems we have now that let us introduce probes into the brain – they deal with straight lines and are only manually guided,” said Joseph Neimat, an associate professor of neurological surgery, who helped the engineers understand how the procedure works in the operating room. “To have a system with a curved needle and unlimited access would make surgeries minimally invasive. We could do a dramatic surgery with nothing more than a needle stick to the cheek.”
Mechanical engineering graduate student David Comber and associate professor Eric Barth watched Neimat perform surgeries to quell epileptic episodes. They developed their robot to match the needs and incorporated associate engineering professor Robert Webster’s steerable needle system, which is made of multiple nested tubes of shape memory alloy that extend through compressed air. When the needle tip needs to curve in a direction, a curved tube is added to the length. Their system lets the needle maneuver through the cheek opening and under the brain until it gets to the hippocampus region.
The team, which includes 3-D printing experts at the Milwaukee School of Engineering, will next try their robotic surgery on cadavers.
(Patient mockup of surgical robot designed to treat epilepsy by entering the brain through the cheek. Image courtesy of the Vanderbilt Laboratory for the Design and Control of Energetic Systems.)
Top Image: The Vanderbilt University mechanical engineering team showed their robotic brain surgery device at a recent conference. Here, the device’s docking tube mount is shown on a demonstration skull with the steerable needle inserted into the cheek bone. Courtesy David Comber/Vanderbilt University.