An acetone‐based phantom for quantitative diffusion MRI

摘要

Purpose To propose and evaluate an acetone–D 2 O phantom that has an extended range of apparent diffusion coefficient (ADC) for quantitative diffusion magnetic resonance imaging (MRI), as well as to compare its properties to previously described water‐based phantoms. Materials and Methods The proposed acetone–D 2 O, and previously described sucrose water solution and polyvinylpyrrolidone (PVP) water solution phantoms, were constructed in a number of concentrations between 0% and 50%. At 1.5T field strength, diffusion‐weighted MR spectroscopy (DW‐MRS), based on a point‐resolved spectroscopy (PRESS) acquisition, nondiffusion‐weighted stimulated echo acquisition mode (STEAM)‐MRS, and diffusion‐weighted echo‐planar imaging (DW‐EPI) were used to evaluate each phantom. The MR spectra, diffusion‐weighted signal decay pattern, tunability of ADC, and ADC range of each phantom were all evaluated. Results When placed in an ice‐water bath, all phantoms provided desirable signal properties, including single‐peak signal with Gaussian diffusion and tunable ADC. At 0°C, however, water‐based phantoms had ADC limited to less than 1.1·10 ?3 mm 2 ·s ?1 (0.2–1.1·10 ?3 mm 2 ·s ?1 ), while the proposed acetone‐based phantom had ADC values spanning a wider range (0.6–3.5·10 ?3 mm 2 ·s ?1 ). Conclusion The proposed acetone–D 2 O phantom provided desirable signal properties over a wide range of ADCs with temperature controlled using an ice‐water bath. Level of Evidence: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1683–1692.