Image-guided neurosurgical tool continues to grow from BME Design to award-winning prototype

Magnetic resonance image-guided brain surgery enables a host of new transformative surgeries with dramatic improvements in outcomes. Rather than resecting brain tissue away to get to the focal point where elliptic seizures begin, a 2-millimeter laser catheter can be inserted through a small opening into the skull and guided to the desired location with millimeter precision. Once the catheter is in place, MRI can precisely monitor the heating zone so only the desired tissue is eliminated as an epileptic source. Recoveries are much quicker and much less collateral damage results.

The problem is the surgical device used to gain skull entry and align the laser in the magnetic resonance suite, known as a brain device guide, takes 80 to 120 minutes to use and is much more complex than the equipment surgeons normally use. In many applications requiring treatment on both sides of the brain, the total surgical time balloons to all day. Dr. Azam Ahmed, a neurosurgeon at UW Health and associate professor of neurological surgery in the School of Medicine and Public Health, wanted to create a guide that was faster and offered much more reliable procedure times, so he turned to the UW-Madison Biomedical Engineering Design program.

Ahmed had a general idea on how to avoid the iterative imaging and gear manipulation needed to align the current commercial option. In his mind, the infinite possibilities created by the gear system created the long procedural times. In 2017, he and collaborator Dr. Terrence Oakes pitched a project to a biomedical engineering design team to create a smaller, simpler device that creates a set of discrete possible brain trajectories. The students delivered on a prototype that would require only one imaging step to define the setting to align the trajectory. With a well-defined trajectory, smaller 2- to 4-millimeter holes through skulls would be needed instead of the 12-millimeter burr holes currently used.

With the help of the Wisconsin Alumni Research Foundation, Azam, Oakes and the BME students (Caitlin Randell, Zach Hite, Molly De Mars, Bailey Ramesh, Mark Nyamee and Haley Yagodinski) patented the design concept in 2018. Azam, Oakes, Medical Physics and Psychiatry Professor Andrew Alexander and I formed a company called ImgGyd in 2020 to derisk the concept.

The patent was granted to WARF at the end of 2021. ImgGyd was awarded a Phase 1 Small Business Innovation Research grant from the National Institutes of Health in 2022, which allowed our company to develop and validate a second-generation prototype and related software. We’ve dubbed the device the AccuGyd.

UW-Madison medical physics graduate student Tom Lilieholm developed the companion software that uses 3D images to recognize the 3D orientation of the AccuGyd and pick two settings that define the trajectory course through the brain. His work was selected for publication at the 23rd Designing Medical Devices conference held April 8-10, 2024, at the University of Minnesota Bakken Medical Device Center. Lilieholm was further invited to compete with seven other participants in an international cohort to make 5-minute pitches judged by experts from Medtronic, Boston Scientific, Solventum and others in the Minneapolis medical technology venture capital community. Lilieholm and AccuGyd earned third place.

The market opportunities are rich for such a device in other applications such as deep brain stimulator placement, intracerebral hemorrhage treatment, and a new horizon in gene delivery to cure devastating rare neurodegenerative diseases in children. In many cases, innovators like UW-Madison Professors Kris Saha and Shaoqin “Sarah” Gong are racing ahead with solutions in viral and nanoparticle treatments for these diseases, but methods to treat wider tracts of the brain are lacking.