Determination of pre-emphasis constants for eddy current reduction

0350811 - ÚPT 2011 RIV GB eng J - Journal Article
Bartušek, Karel - Kubásek, R. - Fiala, P.
Determination of pre-emphasis constants for eddy current reduction.
Measurement Science and Technology. Roč. 21, č. 10 (2010), 105601:1-9. ISSN 0957-0233. E-ISSN 1361-6501
R&D Projects: GA ČR GA102/09/0314
Institutional research plan: CEZ:AV0Z20650511
Keywords : magnetic field gradient * magnetic resonance imaging * measurement technique
Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering
Impact factor: 1.350, year: 2010

Magnetic field gradients play a fundamental role in fast magnetic resonance imaging (MRI) methods and spectroscopy imaging. Precise information on gradient waveform shape and rise times is often very useful in experimental MRI. We present a simple method for the measurement of the gradient time course and static magnetic field changes. The method does not require any specialized hardware and can be used with a standard volume coil and a special phantom filled with deionized or doped water. The method is based on an analysis of the instantaneous frequency variation of an MR signal in the time domain, acquired from a mechanically selected thin slice of phantom located at the gradient isocentre. The measurement and approximation of the course of time gradients and of the changes in the static magnetic field result in pre-emphasis constants that substitute the constants determined manually in a time-consuming manner.
Permanent Link: http://hdl.handle.net/11104/0190714