Portable Brain-Mapping Device Is More Accurate, Less Costly, Than fMRI
March 12, 2009
Two Japanese scientists will arrive at the University of Houston next month to help develop a unique brain-mapping device that promises to deliver more comprehensive and accurate insights into the mind at a fraction of the cost of current technologies.
In April, Mikio Kubota of Seijo University and Mayako Inouchi of Waseda University will join the research team at UH's Biomedical Imaging Lab. There they will work as visiting faculty members with lab director George Zouridakis in expanding a noninvasive technology that may offer a more thorough understanding of brain activities and help diagnose traumatic brain injuries in emergency rooms and on the battlefield.
The device the team has in the works fits on a patient's head, Zouridakis explained, and its configuration of fiber optics and special electrodes sends light, via laser diodes, into the brain. The light, which becomes scattered as it travels through the layers of the brain tissue, is then reflected back out of the brain and is measured by a set of sensors. It is the reflected light's unique properties that indicate what's going on in the brain, he said.
"The typical approach currently used for brain mapping is functional magnetic resonance imaging, or fMRI," said Zouridakis, associate professor at UH's College of Technology. "However, an fMRI scanner is expensive, on the order of millions of dollars, and confined in one place, as it requires a shielded room because of the strong magnetic fields. It also requires specialized personnel to maintain and operate."
Zouridakis said his team aims to eliminate such obstacles. "Our technology marries high-density electroencephalography, or EEG, which measures the electrophysiological activity of the brain, with near-infrared spectroscopy, or NIRS, which provides information about cerebral blood flow," Zouridakis said. "Like the EEG, NIRS is portable, costs only about $200,000, does not need a special room or personnel to maintain, and can quantify both direct and indirect measures of brain activity."
Combining the merits of EEG and NIRS, Zouridakis explained, will allow the team to study both electrical and metabolic activities at the same time and improve patient benefits.
"Typically, two separate tests are done on a patient at two different times - probably on different days - one to get the metabolic aspects and another to capture the electrophysiological aspects of brain activation," Zouridakis said. "However, the brain is dynamic, and, thus the two recordings do not represent the same brain activity. What we propose is to get both aspects simultaneously so that the information obtained is truly complementary."
Dr. Luca Pollonini, who joined Zouridakis' team in September as a research associate, said he hopes one day the combination of the EEG and NIRS will more accurately diagnose brain damage in hospitals and on the battlefield.
"What I envision is a very portable device that, by combining two or more techniques, can be used for example for rapid assessment of traumatic brain injury," said Pollonini, who collaborates with Nirox, an Italian company established in 2005 to commercialize NIRS technologies. "If I rush into the ER because my kid fell off his bike and I want to be sure he is fine, the only way now to assess brain injury is to run a CT scan, which delivers radiation to the body, or a MRI scan, for which you have to be immobile. With pain and emotional distress emerging after a traumatic episode, it is hard for everybody to stay still during these examinations," Pollonini said.
In 2002, George Zouridakis was instrumental in developing the first truly portable EEG equipped with 256 data-recording sensors, or electrodes. Built by BioSemi in The Netherlands, it employs active electrodes, which are loaded with microchips, to eliminate environmental noise.
Courtesy: University of Houston.