It may soon be possible to scan the brain without radiation or bulky magnets. In the journal Nature Photonics, scientists from the School of Medicine at Washington University in St. Louis (WUSTL), have presented a new optical approach to brain scanning, comparable to PET and MRI, which are currently the state-of-the-art when it comes to scanning the brain.
The new approach called DOT uses tiny LED lights to track the happenings in a brain.
Though DOT has been around for more than 10 years, its use has been limited to research because it could not thus far go beyond scanning small regions of the brain at a time. But the authors of this study have uncovered a new version of DOT that may serve as a surrogate for fMRI.
Capable of covering two-thirds of the skull, the new system can scan activity in several regions and networks of the brain, including those associated with language and self-reflection. This has never happened before.
DOT is tailor made for children as it does not curtail movement during the scans says senior author Joseph Culver, associate professor of radiology. “Also, the improvement in image quality means that we are getting much closer to the accuracy of fMRI.” Moreover, for patients with pacemakers and other implanted devices for whom MRI is not an option, DOT is the way to go.
Since MRI uses magnetic fields it poses an unacceptable risk for patients with implants. DOT, on the other hand, is completely safe. Also, DOT can be designed to be portable, allowing the scanner to be brought to the patient’s bedside or into the operating room.
Positron emission tomography (PET), another commonly used method for mapping brain activity, uses radiation and, therefore, can be used only sparingly.
DOT uses neither magnets nor radiation and so can be used multiple times to monitor patients with brain injury, autism or progressive brain diseases such as Parkinson’s.
When the researchers ran DOT against fMRI on the same subjects and scanned a key area of the frontal lobe used in language and speech, they found an approximate 75% overlap between the scans produced by the two technologies.