New assistive technologies allowing high-risk neurovascular procedures to be done more widely and easily are being developed by an interdisciplinary team of surgeons and engineers at Vanderbilt University Medical Center. One technology will provide neurosurgeons with accurate, real-time information about the location of a moving catheter. The other will create self-navigating catheters that can move through complex twists and bends in major blood vessels during thrombectomies in the brain.
“Our goal is to develop technologies that clarify, simplify and speed up the process of removing a clot. Time is brain,” said Rohan Chitale, M.D., an assistant professor of neurological surgery at Vanderbilt.
“Our goal is to develop technologies that clarify, simplify and speed up the process of removing a clot. Time is brain.”
Chitale is leading the efforts in close partnership with Nabil Simaan, Ph.D., a professor of mechanical engineering, computer science and otolaryngology at Vanderbilt. The work falls within the Vanderbilt Institute for Surgery and Engineering.
Beyond X-Rays to Real-Time Images
While manipulating a flimsy catheter that is more than a meter long, Chitale says a neurosurgeon receives extremely limited tactile feedback. They rely on still X-ray roadmaps to guide a catheter to the right position to suction out a clot, but this approach has drawbacks.
“When you move the catheter and wires, the blood vessels move, too. Still X-ray shots don’t capture that movement,” Chitale said. As a result, he says neurosurgeons must make inferences resting heavily on previous experience.
The research aims to remove existing perception barriers that neurosurgeons face while executing endovascular procedures. “Using artificial intelligence techniques, the technology we’re developing will provide a more objective measure of where the catheters are located while we are moving them,” Chitale said. “With more precise, real-time information, we’ll be able to move beyond relying on just still images and experience.”
“With more precise, real-time information, we’ll be able to move beyond relying on just still images and experience.”
This sensory augmentation work is in its early stages, Chitale says. The team is applying for grants to test their approach.
Robotic Catheter Navigation
A second innovation could enable semi-autonomous navigation of the catheters used to remove a blockage in a major brain vessel. Chitale’s team is working on a robot that will automatically guide the catheter through bends and twists.
“With large vessel occlusions, quick removal can make a great difference in terms of keeping the patient from becoming severely disabled or debilitated,” he said. “Our system promises to help surgeons who don’t regularly go up into these blood vessels.”
“Our system promises to help surgeons who don’t regularly go up into these blood vessels.”
Additionally, future iterations of such a system would allow a neurosurgeon working in Germany to operate on a patient in Tennessee, Chitale explained. This research is also in its early stages; the researchers are working with in vitro phantom vascular models.
A Golden Age for Stroke Treatment
Chitale, whose father was also a neurosurgeon, has always been interested in the anatomy of the brain. He appreciates that his research tests the limits of his abilities and places him at the frontiers of what some call a “golden age” of acute stroke treatment.
However, Chitale says the real inspiration “lies in doing the kind of work where you become a part of patients’ lives, where they really need you, and you develop those personal connections.”