Diffuse optical technology, or DOT, is closing in on the accuracy of the industry standard: functional MRI. Though the fMRI is accurate, it requires the patient to be immobilized in the machine, restricting how useful it is for understanding how the brain responds to stimuli.
In a study recently published in Nature Photonics, researchers debuted a new DOT, or diffuse optical tomography, instrument that could see two-thirds of the head and depict brain processes that take place in multiple regions and brain networks, such as those involved in language. The researchers, led by Joseph Culver, a radiologist at Washington University of St. Louis, compared the maps of activity created by DOT and fMRI scans and found a 75 percent overlap.
DOT itself isn’t new. For about a decade, doctors and researchers have looked to it as a more portable and safer alternative to fMRI scans. MRI technology uses magnets which interfere with the functioning of medical devices including pacemakers and cochlear implants. PET scans, another common method of coaxing a brain to do the equivalent of say ah, expose patients to significant levels of radiation.
“When the neuronal activity of a region in the brain increases, highly oxygenated blood flows to the parts of the brain doing more work, and we can detect that. It’s roughly akin to spotting the rush of blood to someone’s cheeks when they blush,” Culver said in a news release.
With their latest readings, DOT could potentially be used when an fMRI doesn’t make sense. Because it’s portable, it could be used in operating rooms or patients’ hospital rooms.
Imagine a totable brain scan that could be used repeatedly without health risk. Doctors could track the physical progress of patients recovering from brain injuries. They could also monitor the effects of brain diseases such as Alzheimer’s and Parkinson’s diseases and potentially disorders like autism. Potentially, patients could wear the device as it sends back brain activity from real-world situations.
In the current paper, Culver and his colleagues showed that DOT could be used to observe how electrical stimulation of the brain lessens Parkinson’s symptoms—something that can’t be done with magnetic resonance imaging — and they indicate they are likely to dive deeper into that project. Electrical stimulation has also been proposed as a treatment for Alzheimer’s disease.
When it comes to these ravaging, widespread and poorly understood conditions, better research methods are not just an inside baseball development — they could mean better treatments.
Photos: Mickey Winn, Jan Ainali / Wikimedia Commons, Tim Parker