Edited by Charles P. Slichter, University of Illinois at Urbana-Champaign, Urbana, IL, and approved January 28, 2012 (received for review October 20, 2011)
Magnetic resonance imaging (MRI) of solids is rarely attempted. One of the main reasons is that the broader MR linewidths, compared to the narrow resonance of the hydrogen (1H) in free water, limit both the attainable spatial resolution and the signal-to-noise ratio. Basic physics research, stimulated by the quest to build a quantum computer, gave rise to a unique MR pulse sequence that offers a solution to this long-standing problem. The “quadratic echo” significantly narrows the broad MR spectrum of solids. Applying field gradients in sync with this line-narrowing sequence offers a fresh approach to carry out MRI of hard and soft solids with high spatial resolution and with a wide range of potential uses. Here we demonstrate that this method can be used to carry out three-dimensional MRI of the phosphorus (31P) in ex vivo bone and soft tissue samples.
Author contributions: M.A.F., M.M., K.L.I., J.A.M., and S.E.B. designed research; M.A.F., M.M., J.N.V.H., and S.E.B. performed research; M.A.F., J.N.V.H., and S.E.B. analyzed data; and M.A.F., M.M., J.N.V.H., K.L.I., J.A.M., and S.E.B. wrote the paper.
Conflict of interest statement: Yale University has applied for a patent relating to the method described in this paper (S.E.B. is a coinventor).
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1117293109/-/DCSupplemental.
