Wieland A Worthoff1, Aliaksandra Shymanskaya1,2, N Jon Shah1,2,3. 1. Institute of Neuroscience and Medicine - 4, Forschungszentrum Jülich GmbH, Jülich, Germany. 2. Institute of Neuroscience and Medicine - 11, Forschungszentrum Jülich GmbH, Jülich, Germany. 3. Faculty of Medicine, Department of Neurology, RWTH Aachen University, Aachen, Germany.
Abstract
PURPOSE: Sodium imaging delivers valuable information about in vivo metabolism and pathophysiology. Image quantification can benefit the diagnosis and characterization of existing pathologies and the clinical course of a disease. An enhanced SISTINA sequence is proposed for sodium imaging and for the estimation of sodium tissue parameters for a 2-compartment model of the brain, such as relaxation times in intracellular space and tissue, intracellular volume fraction, and intracellular molar fraction. The aim of the research is to demonstrate how a 2-compartment model can be parameterized to sufficiently describe tissue sodium concentrations and dynamics by performing relaxometry with such a sequence. METHODS: Multiple quantum filtered sodium signals were detected using an enhanced SISTINA sequence (consisting of 3 consecutive RF pulses) by placing a readout train between the first and second RF pulse, and 1 after the third pulse. Semiautomatic segmentation using singular value decomposition and manual segmentation was applied to the images. RESULTS: Analysis was performed on 40 healthy volunteers in a 4T scanner, yielding bi-exponential relaxation times of brain tissue, intracellular sodium molar and volume fraction, intracellular sodium concentration, as well as sodium tissue concentration in the scope of a considered model. Two models with either purely mono-exponential or bi-exponential relaxing extracellular sodium were used with and without a potential contribution of triple quantum-filtered signal from extracellular space. CONCLUSION: An estimation of relaxation properties and concentrations limited to the assumed model is possible from a single sequence. The achieved results agree well with those reported in literature.
PURPOSE:Sodium imaging delivers valuable information about in vivo metabolism and pathophysiology. Image quantification can benefit the diagnosis and characterization of existing pathologies and the clinical course of a disease. An enhanced SISTINA sequence is proposed for sodium imaging and for the estimation of sodium tissue parameters for a 2-compartment model of the brain, such as relaxation times in intracellular space and tissue, intracellular volume fraction, and intracellular molar fraction. The aim of the research is to demonstrate how a 2-compartment model can be parameterized to sufficiently describe tissue sodium concentrations and dynamics by performing relaxometry with such a sequence. METHODS: Multiple quantum filtered sodium signals were detected using an enhanced SISTINA sequence (consisting of 3 consecutive RF pulses) by placing a readout train between the first and second RF pulse, and 1 after the third pulse. Semiautomatic segmentation using singular value decomposition and manual segmentation was applied to the images. RESULTS: Analysis was performed on 40 healthy volunteers in a 4T scanner, yielding bi-exponential relaxation times of brain tissue, intracellular sodium molar and volume fraction, intracellular sodium concentration, as well as sodium tissue concentration in the scope of a considered model. Two models with either purely mono-exponential or bi-exponential relaxing extracellular sodium were used with and without a potential contribution of triple quantum-filtered signal from extracellular space. CONCLUSION: An estimation of relaxation properties and concentrations limited to the assumed model is possible from a single sequence. The achieved results agree well with those reported in literature.
Authors: Aliaksandra Shymanskaya; Wieland A Worthoff; Gabriele Stoffels; Johannes Lindemeyer; Bernd Neumaier; Philipp Lohmann; Norbert Galldiks; Karl-Josef Langen; N Jon Shah Journal: Mol Imaging Biol Date: 2020-02 Impact factor: 3.488
Authors: Alexander Heinzel; Daniela Dedic; Norbert Galldiks; Philipp Lohmann; Gabriele Stoffels; Christian P Filss; Martin Kocher; Filippo Migliorini; Kim N H Dillen; Stefanie Geisler; Carina Stegmayr; Antje Willuweit; Michael Sabel; Marion Rapp; Michael J Eble; Marc Piroth; Hans Clusmann; Daniel Delev; Elena K Bauer; Garry Ceccon; Veronika Dunkl; Jurij Rosen; Caroline Tscherpel; Jan-Michael Werner; Maximilian I Ruge; Roland Goldbrunner; Jürgen Hampl; Carolin Weiss Lucas; Ulrich Herrlinger; Gabriele D Maurer; Joachim P Steinbach; Jörg Mauler; Wieland A Worthoff; Bernd N Neumaier; Christoph Lerche; Gereon R Fink; Nadim Jon Shah; Felix M Mottaghy; Karl-Josef Langen Journal: Cancers (Basel) Date: 2022-07-08 Impact factor: 6.575