An Acetone-Based Phantom for Quantitative Diffusion MRI

Purpose: To propose and evaluate an acetone-D2O 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-D2O, 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 degrees 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-D2O phantom provided desirable signal properties over a wide range of ADCs with temperature controlled using an ice-water bath.