Abstract
Surface coils are employed for rotating-frame zeugmatography experiments to accomplish one-dimensional 31P metabolite mapping in phantoms and bovine eyes. The spatially dependent β1 field of the surface coil provides the necessary magnetic field gradient, and the experiments are designed to acquire 15-32 spectra obtained with rf pulses of equally incremented durations. Regions of the sample are distinguished on the basis of the differing magnetization precessional rates about the spatially dependent β1 field. Thus the mapping dimension corresponds to changes in the transverse (x′y′) magnetization components of the β1 field, which correspond to successive curved surfaces of constant β1 field strength. Two-dimensional Fourier transform processing of the data results in a metabolite map composed of a suite of spectra displayed as a function of the mapping dimension. Experiments with bovine eye phantoms reveal that T1 discrimination can produce a loss of resolution due to smearing in the mapping dimension. Resonance offset effects are also apparent at distances removed from the coil. Elimination of the T1 discrimination-induced smearing is demonstrated through the incorporation of a saturation pulse into the experiment. Application of the method to the intact bovine eye is shown to result in metabolite maps delineating contributions from constituent ocular tissues of the bovine eye.
Original language | English (US) |
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Pages (from-to) | 268-279 |
Number of pages | 12 |
Journal | Journal of Magnetic Resonance (1969) |
Volume | 60 |
Issue number | 2 |
DOIs | |
State | Published - Nov 1984 |
Bibliographical note
Funding Information:Supported by grants from the National Eye Institute (EY 04033), the W. M. Keck Foundation, and the Estate of M. J. Davidson to T.S. We thank P. Campbell and J. Willis for helpful discussions during the course of this work. G. Acosta gratefully acknowledges fellowship support from tbe U.S. Dept. of Education Graduate and Professional Opportunity Program.