Magazine article Clinical Psychiatry News
DT-MRI Moving from Lab to Neuropsychiatry. (Traces Brain's Fiber Pathways)
Once only a laboratory curiosity, diffusion tensor MRI may eventually deliver promising neuropsychiatric applications ranging from screening tools to prognosis guides. But investigators caution that these applications may be as much as 5-10 years from the clinic.
Developed at the National Institute of Child Health and Human Development in Bethesda, Md., the diffusion tensor (DT)-MRI or DT imaging technique can produce three-dimensional images of the orientation and pathways of fiber pathways in the brain and other soft tissue.
The technique measures the diffusion of water molecules. In tissue with no preferred orientation, such as gray matter in the brain, water diffuses isotropically, in all directions equally.
But where there are parallel fibers, such as in the brain's white matter or in striated muscle, water molecules tend to diffuse anisotropically, along the direction of the fiber.
"If we could establish a strong connection between an anatomical deficit and a particular disorder, it might be possible to one day use DT-MRI as a screening tool," said Peter Basser, Ph.D., the National Institute of Child Health and Human Development investigator who is the technique's principal inventor.
The National Institutes of Health recently signed an agreement with GE Medical Systems licensing the company to produce and market the product.
According to GE spokesman Patrick Jarvis, the DT-MRI technology is available for some of the company's 1.5- and 3-tesla MRI systems. Several hundred such systems have already been shipped to hospitals.
DT-MRI proved its clinical utility in the diagnosis of stroke and other brain injuries, where one can observe diffusion changes within minutes, far faster than any other imaging modality.
Dr. Carlo Pierpaoli, a staff scientist at the National Institute of Child Health and Human Development, said in an interview that DT-MRI also can provide specific information that will help determine a patient's prognosis after a stroke. …