The University of New
Hampshire Center for
Xenon Imaging has been
established to investigate
the properties and
utility of hyperpolarized
xenon, particularly
as a contrast agent
in magnetic resonance
imaging. This opportunity
has arisen at UNH due to
our recent demonstration
of breakthrough technology
that overcomes the
natural obstacles to
polarizing xenon. In
order to compare our new
technology to existing
polarizers it is useful
to define a "figure of
merit". Since all xenon
polarizers produce higher
polarizations at lower
production rates, the
figure of merit is defined
as the product of these
two numbers. Our method
produces hyperpolarized
xenon at a figure of
merit that exceeds the
world's second best by
a factor of ten at most
useful polarizations. As
we are approaching the
theoretical maximum
(nearly fully polarized
xenon in nearly unlimited
quantities), we have the
unique opportunity of
exploring the intrinsic
diagnostic potential of
hyperpolarized xenon.
Xenon Polarizer Simulation Code is now online
Oct 2, 2006. Our Xenon Polarizer Simulation Code
is now online. The web interface is still under construction, please check back often.
Boston Globe writes about our work
July 24, 2006. The Boston Globe newspaper wrote an article
about hyperpolarized gas imaging which described work of Dr. Sam Patz
of Brigham and Women's Hospital, our principal collaborator on lung MRI
using hyperpolarized xenon. You can find the article here.
UNH Xenon Polarizer's first publication lands in Physical Review Letters
Feb 10, 2006. Our first report describing the world leading xenon polarizing system
was published in the Physical Review Letters96: 053002 (2006).
Check out our Reports for the content of the paper.
We have in preparation a more detailed description of the system and the results, as well as a
theoretical paper on the polarizer's concept.
UNH polarizer obtains its first image of a human lung
May 04, 2005. Boston, MA -- The UNH polarizer delivered
polarized gas for our first ever human lung image. The polarized gas was thawed directly into
a 1 liter Tedlar bag. The human subject inhaled about 400 cc of enriched
hyperpolarized 129Xe in one inhalation, completing the inhalation with
room air to the lung capacity. We performed two experiments separated by
about 90 min. The experiments were based on an approved IRB protocol. The
experience is a milestone for our group opening the door for performing
human imaging using hyperpolarized 129Xe.
Polarizer operational at Brigham and Women's Hospital
April 22, 2005. Boston, MA -- The UNH 129Xe polarizer produces polarized gas
at Brigham and Women's Hospital in Boston. Moving the Xe polarizer
equipment from UNH to BWH started about a month ago. The polarizer was
reassembled in an annex next to a 0.2 T scanner in the basement of the
hospital. This is the first time the 129Xe polarizer has been moved and
successfully operated off-campus.
Faraday rotation apparatus commissioned and operational
August 23, 2004. Durham, NH -- Using Faraday rotation technique, we
have measured the product of density and polarization of rubidium.
Knowledge of the product is very critical in improving the polarization
in optical pump process. In order to make a precision measurement, we
have built a compact system, based on Littrow grating with a beam
correcting mirror. We have successfully narrowed the width of the
wavelength of 780 nm diode laser far below 0.015 nm; Precision was
limited by the detector resolution. The wavelength was also stable
within 0.001 nm drift in nine hour duration. The figure shown is
Faraday rotation as a function of scanning wavelength. By fitting
the data with theoretical Faraday rotation, we obtained the product,
1.39E12 cm-3 for this data set.
UNH group achieves high efficiency with spectrally-narrowed
laser
March 19, 2004. Durham, NH -- Our existing NIH grant includes
funds for the replacement of the 200W 795nm laser we borrowed
from our nuclear physics program. Instead of purchasing a
duplicate, we have opted to extend the work of Thad Walker and
Bien Chann of the University of Wisconsin on spectrally
narrowed multi-stripe diode lasers. Working with a stack of
five bars capable of 60W each, we recently demonstrated 68%
efficiency at 0.1 nm wavelength at half-maximum current.