September 17, 2013
By James Devitt
Researchers at NYU and NYU Langone Medical Center have created a novel way to enhance MRI by reducing interference from large macromolecules that can often obscure images generated by current chemical exchange saturation transfer (CEST) methods.
Their work, which appeared in the Nature publishing group journal Scientific Reports, has the potential to improve MRI for cartilage as well as for brain tissue.
“We have found a way to eliminate signals of certain molecules and thereby clean up the image of parts of the body that could be used by medical professionals in order to make diagnoses,” explains Alexej Jerschow, a professor in NYU’s Department of Chemistry.
The study’s other authors were: Ravinder Regatte, professor, Departments of Radiology and Orthopedic Surgery, NYU Langone Medical Center; Prodromos Parasoglou, a post-doctoral research Fellow, and Ding Xia, an assistant research scientist, at the Center for Biomedical Imaging, Department of Radiology at NYU Langone Medical Center; and Jae-Seung Lee, an NIH research Fellow who holds appointments in NYU’s Department of Chemistry and NYU Langone Medical Center.
The researchers’ work aims to improve a decade-old method, chemical exchange, which has been used to enhance MRI techniques. Under this approach, scientists exploit the movement of atoms from their natural molecular structure to water in the body in order to enhance their visibility.
In the Scientific Reports work, the researchers focused on improving visibility of glycosaminogycans (GAGs) through MRI. But, in this effort, they sought to block the signaling impact of the macromolecules that obscure the observation of GAGs.
To do so, they took advantage of macromolecules’ broad frequency spectrum—a trait that allows for easy detection and neutralization. Specifically, the researchers could, in effect, “bleach” the signal out by simultaneously using multiple irradiation frequencies. As a result, macromolecular interference diminished and enhanced the quantitative assessment of GAGs.
“This method gives us the opportunity to correct existing CEST methods by focusing on molecular signals of interest with much better precision than currently exists,” explains Regatte.
The research was supported by grants from the National Institutes of Health and the National Science Foundation.