A phantom for diffusion-weighted MRI (DW-MRI)

作者：Lavdas Ioannis^*; Behan Kevin C; Papadaki Annie; McRobbie Donald W; Aboagye Eric O

来源：Journal of Magnetic Resonance Imaging, 2013, 38(1): 173-179.

DOI：10.1002/jmri.23950

• diffusion-weighted MRI
• tissue-equivalent diffusivity materials
• diffusion phantom
• apparent diffusion coefficient
• temporal stability
• reproducibility

Purpose: To develop tissue-equivalent diffusivity materials and build a spherical diffusion phantom which mimics the conditions typically found in biological tissues. Also, to assess the reproducibility of ADC measurements from a whole-body diffusion protocol.
Materials and Methods: Nickel-doped agarose/sucrose gels were manufactured and used to build a spherical diffusion phantom with tissue-equivalent relaxation and diffusion compartments. The temporal stability of the gels was monitored for a period of 8 weeks and, using the same measurements, the reproducibility of ADC was assessed in a 1.5 Tesla (T) clinical system.
Results: The temporal stability of the nickel-doped agarose/sucrose gels diffusion properties was excellent (average coefficient of variation [CV] for ADC in all phantom compartments = 1.27%). The average CV for ADC measurements, excluding the phantom compartments affected by artifacts, was 0.76% showing that the reproducibility of ADC measurements using an EPI DW-MRI protocol is very good.
Conclusion: Nickel-doped agarose/sucrose gels can be used as reference materials for MRI diffusion measurements and show excellent short-term stability with respect to ADC. A phantom made of these materials can be invaluable in optimizing DW-MRI protocols, developing novel pulse sequences for DW-MRI, or comparing ADC values among field strengths, vendors, and imaging centers.

• 出版日期2013-7