Boston University

Optical Characterization and Nanophotonics Laboratory








Hyperpolarized Xenon Magnetic Resonance Imaging

Members: Anna K. Swan


Alumni: Gregory Paul Blasche, Zach Dietz, Bennett B. Goldberg, Masaki Horii, Joey K. Mansour, Michelle Plante, Hillary Trent, Peter Velikin, Arvind Venkatesh


Building a Better MRI

Scientists at Boston Univesity's Photonics Center, are collaborating with doctors at Brigham and Women's Hospital and Harvard Medical School, on the further development of a new form of magnetic resonance imaging (MRI) that will significantly improve the quality of images of the lungs, blood vessels, and brain - organs with a low water content or those with high content of lipids (fat) that are difficult to examine with traditional MRI techniques.

The new technology uses a hyperpolarized form of the noble gases helium and xenon, which is extremely soluble in lipids. Conventional magnetic resonance imaging relies on the strong signal from water protons, abundant in living organisms, but which often produces low contrast images. This is particularly problematic in imaging the lungs and lipid parts of nerves and the brain - most significantly the perfusion of the white matter of the brain which is currently inaccessible to any form of MRI. Non-hyperpolarized xenon is only moderately detectable by MRI, and virtually undetectable at the concentrations attainable in living organisms. When xenon is hyperpolarized, however, its detectability is enhanced by about a hundred thousand times - producing extremely high resolution MRI images.

Professors Bennett Goldberg, associate professor of physics and of electric and computer engineering and Selim Unlu, assistant professor of electrical and computer engineering, together with Dr. Mitchell Albert of Brigham and Woman's Hospital, will develop the stable, high-power, diode-laser driven optical pumping apparatus necessary to produce the large quantities of hyperpolarized xenon which are key to the success of the system.

The multi-disciplinary research team, combining expertise ranging from optical engineering and atomic physics to MRI technology and physiology, is funded by the National Science Foundation.

Photo: An intensity/spectral map (left) of a typical commercial diode-laser shows large wavelength variations. It clearly illustrates the engineering challenge involved in producing the very high power, but narrow linewidth laser needed to produce the noble gases utilized in this process; an image of lungs (right) using the new MRI technique

See the CLEO 2003 Presentation


W. Zhou, and G. P. Blasche, "Injection-Locked Dual Opto-Electronic Oscillator With Ultra-Low Phase Noise and Ultra-Low Spurious Level," IEEE Transactions on Microwave Theory and Techniques, Vol. 53, No. 3, March 2005, pp. 929-933

A. Venkatesh, A. X. Zhang, J. K. Mansour, L. Kubatina, C. H. Oh, G. P. Blasche, M. S. Ünlü, D. Balamore, F. A. Jolesz, B. B. Goldberg, and M. S. Albert, "MRI of the lung gas-space at very low-field using hyperpolarized noble gases," Magnetic Resonance Imaging, Vol. 21, No. 7, September 2003, pp. 773-776

G. P. Blasche, B. B. Goldberg, and M. S. Ünlü, "Thermal profile of high power laser diode arrays and implications in line-narrowing using external cavities," Proceedings of CLEO/QELS 2003, June 2003

A. Venkatesh, "Hyperpolarized Xenon MRI of the Brain," Ph.D. Dissertation, May 2001


This project is a collaboration with Brigham and Women's Hospital and is funded by a grant from National Science Foundation.

© 2007 Trustees of Boston University. All rights reserved.  |  Last modified April 16, 2007 at 12:00 AM EDT