Optimization of single voxel MR spectroscopy sequence parameters and data analysis methods for thermometry in deep hyperthermia treatments

Objective:The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic reson...

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Hauptverfasser: Hartmann, Josefin (VerfasserIn) , Pyatykh, Stanislav (VerfasserIn) , Hesser, Jürgen (VerfasserIn)
Dokumenttyp: Article (Journal)
Sprache:Englisch
Veröffentlicht: 2017
In: Technology in cancer research & treatment
Year: 2016, Jahrgang: 16, Heft: 4, Pages: 470-481
ISSN:1533-0338
DOI:10.1177/1533034616656310
Online-Zugang:Verlag, kostenfrei, Volltext: http://dx.doi.org/10.1177/1533034616656310
Verlag, kostenfrei, Volltext: https://doi.org/10.1177/1533034616656310
Volltext
Verfasserangaben:J. Hartmann, MSc, J. Gellermann, MD, T. Brandt, MSc, M. Schmidt, PhD, S. Pyatykh, PhD, J. Hesser, PhD, O. Ott, MD, R. Fietkau, MD, and C. Bert, PhD
Beschreibung
Zusammenfassung:Objective:The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments.Materials and Methods:Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated.Results:Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3 voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle.Conclusion:The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry.
Beschreibung:Gesehen am 25.07.2018
First Published July 14, 2016
Beschreibung:Online Resource
ISSN:1533-0338
DOI:10.1177/1533034616656310