Počet záznamů: 1

Determination of pre-emphasis constants for eddy current reduction

  1. 1.
    0350811 - UPT-D 2011 RIV GB eng J - Článek v odborném periodiku
    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
    Grant CEP: GA ČR GA102/09/0314
    Výzkumný záměr: CEZ:AV0Z20650511
    Klíčová slova: magnetic field gradient * magnetic resonance imaging * measurement technique
    Kód oboru RIV: JA - Elektronika a optoelektronika, elektrotechnika
    Impakt faktor: 1.350, rok: 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.
    Trvalý link: http://hdl.handle.net/11104/0190714