OBJECT: Proton resonance frequency shift (PRFS)-based MR thermometry (MRT) is hampered by heat-induced susceptibility changes when applied in tissues containing fat, e.g., the human breast. In order to assess the impact of fat susceptibility changes on PRFS-based MRT during thermal therapy in the human breast, reliable knowledge of the temperature dependence of the magnetic volume susceptibility of fat, dχ(fat)/dT, is a prerequisite. In this work we have measured dχ(fat)/dT of human breast fat tissue, using a double-reference method to ensure invariance to temperature-induced changes in the proton electron screening constant. MATERIALS AND METHODS: Ex vivo measurements were taken on a 14.1 T five mm narrow bore NMR spectrometer. Breast fat tissue samples were collected from six subjects, directly postmortem. The susceptibility was measured over a temperature range from 24°C to 65°C. RESULTS: A linear behavior of the susceptibility over temperature was observed for all samples. The resulting dχ(fat)/dT of human breast fat ranged between 0.0039 and 0.0076 ppm/°C. CONCLUSION: It is concluded that the impact of heat-induced susceptibility changes of fat during thermal therapy in the breast may not be neglected.
OBJECT: Proton resonance frequency shift (PRFS)-based MR thermometry (MRT) is hampered by heat-induced susceptibility changes when applied in tissues containing fat, e.g., the human breast. In order to assess the impact of fat susceptibility changes on PRFS-based MRT during thermal therapy in the human breast, reliable knowledge of the temperature dependence of the magnetic volume susceptibility of fat, dχ(fat)/dT, is a prerequisite. In this work we have measured dχ(fat)/dT of human breast fat tissue, using a double-reference method to ensure invariance to temperature-induced changes in the proton electron screening constant. MATERIALS AND METHODS: Ex vivo measurements were taken on a 14.1 T five mm narrow bore NMR spectrometer. Breast fat tissue samples were collected from six subjects, directly postmortem. The susceptibility was measured over a temperature range from 24°C to 65°C. RESULTS: A linear behavior of the susceptibility over temperature was observed for all samples. The resulting dχ(fat)/dT of human breast fat ranged between 0.0039 and 0.0076 ppm/°C. CONCLUSION: It is concluded that the impact of heat-induced susceptibility changes of fat during thermal therapy in the breast may not be neglected.
Authors: Sara M Sprinkhuizen; Maurits K Konings; Martijn J van der Bom; Max A Viergever; Chris J G Bakker; Lambertus W Bartels Journal: Magn Reson Med Date: 2010-11 Impact factor: 4.668
Authors: I R Young; J V Hajnal; I G Roberts; J X Ling; R J Hill-Cottingham; A Oatridge; J A Wilson Journal: Magn Reson Med Date: 1996-09 Impact factor: 4.668
Authors: Evdokia M Kardoulaki; Richard R A Syms; Ian R Young; Kaushal Choonee; Marc Rea; Wladyslaw M W Gedroyc Journal: Med Phys Date: 2015-03 Impact factor: 4.071
Authors: Le Zhang; Alex Burant; Andrew McCallister; Victor Zhao; Karl M Koshlap; Simone Degan; Michael Antonacci; Rosa Tamara Branca Journal: Magn Reson Med Date: 2016-10-19 Impact factor: 4.668
Authors: Allison Payne; Robb Merrill; Emilee Minalga; J Rock Hadley; Henrik Odeen; Lorne W Hofstetter; Sara Johnson; Christine Tunon de Lara; Sophie Auriol; Stephanie Recco; Erik Dumont; Dennis L Parker; Jean Palussiere Journal: IEEE Trans Biomed Eng Date: 2021-02-19 Impact factor: 4.538