Synthesized tissue‐equivalent dielectric phantoms using salt and polyvinylpyrrolidone solutions
Magnetic resonance in medicine, 2018•Wiley Online Library
Purpose To explore the use of polyvinylpyrrolidone (PVP) for simulated materials with tissue‐
equivalent dielectric properties. Methods PVP and salt were used to control, respectively,
relative permittivity and electrical conductivity in a collection of 63 samples with a range of
solute concentrations. Their dielectric properties were measured with a commercial probe
and fitted to a 3D polynomial in order to establish an empirical recipe. The material's thermal
properties and MR spectra were measured. Results The empirical polynomial recipe …
equivalent dielectric properties. Methods PVP and salt were used to control, respectively,
relative permittivity and electrical conductivity in a collection of 63 samples with a range of
solute concentrations. Their dielectric properties were measured with a commercial probe
and fitted to a 3D polynomial in order to establish an empirical recipe. The material's thermal
properties and MR spectra were measured. Results The empirical polynomial recipe …
Purpose
To explore the use of polyvinylpyrrolidone (PVP) for simulated materials with tissue‐equivalent dielectric properties.
Methods
PVP and salt were used to control, respectively, relative permittivity and electrical conductivity in a collection of 63 samples with a range of solute concentrations. Their dielectric properties were measured with a commercial probe and fitted to a 3D polynomial in order to establish an empirical recipe. The material's thermal properties and MR spectra were measured.
Results
The empirical polynomial recipe (available at https://www.amri.ninds.nih.gov/cgi-bin/phantomrecipe) provides the PVP and salt concentrations required for dielectric materials with permittivity and electrical conductivity values between approximately 45 and 78, and 0.1 to 2 siemens per meter, respectively, from 50 MHz to 4.5 GHz. The second‐ (solute concentrations) and seventh‐ (frequency) order polynomial recipe provided less than 2.5% relative error between the measured and target properties. PVP side peaks in the spectra were minor and unaffected by temperature changes.
Conclusion
PVP‐based phantoms are easy to prepare and nontoxic, and their semitransparency makes air bubbles easy to identify. The polymer can be used to create simulated material with a range of dielectric properties, negligible spectral side peaks, and long T2 relaxation time, which are favorable in many MR applications. Magn Reson Med 80:413–419, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Wiley Online Library
以上显示的是最相近的搜索结果。 查看全部搜索结果