477. Improvement of 1H-CSI deta using eddy current compensation
نویسندگان
چکیده
منابع مشابه
Localized eddy current compensation using quantitative field mapping.
Eddy current effects induced by switched gradients in proximal conducting structures are traditionally reduced by applying preemphasis currents whose amplitudes and decay characteristics must be set to offset the eddy current fields. We present an expeditious, localized, and quantitative method for mapping and adjusting the parameters for eddy current compensation. Mapping is based on analysis ...
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Accurate phasing of MRS spectra is often difficult unless time varying phase effects produced by gradient-induced eddy currents that persist during data acquisition are eliminated. This effect is particularly problematic in 1H-CSI spectra where frequency shifts produced by static field inhomogeneity and phase shifts produced by eddy currents combine. In this paper we present a method that corre...
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Introduction: Clinical diffusion-weighted imaging (DWI) often employs a single-shot echo-planar imaging (EPI) readout to increase acquisition speed. This comes at a cost, however, since conventional DWI sequences employ a spin echo (SE) sequence with either unipolar or bipolar diffusion-sensitizing gradients on both sides of the 180º refocusing pulse. This configuration shortens the separation ...
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This paper presents an inverse problem methodology in the domain of non-destructive testing, and more precisely eddy-current testing. Our objective is to use a precise but expensive-to-evaluate model of the electromagnetic induction phenomenon in a conductive material and to estimate the characteristics of a flaw by minimization of a regularized criterion with the Expected Improvement (EI) glob...
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ژورنال
عنوان ژورنال: Japanese Journal of Radiological Technology
سال: 1994
ISSN: 0369-4305,1881-4883
DOI: 10.6009/jjrt.kj00003326276