Researchers at UC San Diego developed a thin-film device that could help neurosurgeons visualize information about a patient’s brain.
The technology combines an electrode grid and LEDs to track and produce a visual representation of brain activity in real-time during surgery. It allows surgeons to monitor brain states during interventions to remove brain lesions, including tumors and epileptic tissue.
Each LED in the device mirrors the activity of a few thousand neurons. This helps to effectively track and display neural activity in the brain corresponding to different areas of the body. Researchers tested the technology in proof-of-concept experiments in rodents and large non-primate mammals. The LEDs light up red in the areas that need to be removed by surgeons, while surrounding areas they should avoid show up in green.
According to a post on the UCSD website, the study showed that the device can visualize the onset and map the propagation of an epileptic seizure on the surface of the brain. This could enable physicians to isolate brain nodes involved in epilepsy. It could also allow them to deliver the necessary treatment by removing tissue or using electrical pulses to stimulate the brain.
“Neurosurgeons could see and stop a seizure before it spreads, view what brain areas are involved in different cognitive processes, and visualize the functional extent of tumor spread. This work will provide a powerful tool for the difficult task of removing a tumor from the most sensitive brain areas,” said Dr. Daniel Cleary, one of the study’s coauthors. Cleary is a neurosurgeon and assistant professor at Oregon Health and Science University. He was a medical resident and a postdoctoral researcher at the University of California San Diego.
A team of engineers and physicians from UCSD and Massachusetts General Hospital, led by Shadi Dayeh, developed the device. They laid out the details of their work in the April 24 issue of the journal Science Translational Medicine.
According to UCSD, physicians need to map brain function during brain surgery to define which areas control critical functions and can’t be removed. Current methods require working with electrophysiologists during the procedure to achieve this. However, with EP teams and monitoring equipment located in a different part of the OR, brain areas have to be marked on a paper by the EPs or verbally communicating the information to the surgeon.
“Both are inefficient ways of communicating critical information during a procedure, and could impact its outcomes,” said Dr. Angelique Paulk of MGH, study co-author and co-inventor of the technology.
Electrodes currently used in brain monitoring during surgery also fail to produce detailed, fine-grained data, the researchers say. That leads to surgeons leaving a buffer zone (resection margin) around the area removed inside the brain. That means they may leave some harmful tissue. However, the team says their device could provide enough detail to shrink the buffer zone from 5-7 millimeters to less than one millimeter.
“We invented the brain microdisplay to display with precision critical cortical boundaries and to guide neurosurgery in a cost-effective device that simplifies and reduces the time of brain mapping procedures,” said Shadi Dayeh, the paper’s corresponding author and a professor in the Department of Electrical and Computer Engineering at the UC San Diego Jacobs School of Engineering.