Magnetic resonance elastography (MRE) measurements of shear stiffness (μ) in a spherical phantom experiencing both static and cyclic pressure variations were compared to those derived from an established pressure-volume (P-V)-based model. A spherical phantom was constructed using a silicone rubber composite of 10 cm inner diameter and 1.3 cm thickness. A gradient echo MRE sequence was used to determine μ within the phantom at static and cyclic pressures ranging from 55 to 90 mmHg. Average values of μ using MRE were obtained within a region of interest and were compared to the P-Vderived estimates. Under both static and cyclic pressure conditions, the P-V- and MRE-based estimates of μ ranged from 98.2 to 155.1 kPa and 96.2 to 150.8 kPa, respectively. Correlation coefficients (R2) of 0.98 and 0.97 between the P-V and MRE-based estimates of shear stiffness measurements were obtained. For both static and cyclic pressures, MRE-based measures of μ agree with those derived from a P-V model, suggesting that MRE can be used as a new, noninvasive method of assessing μ in sphere-like fluid-filled organs such as the heart.
- Cardiac MRE
- Gated MRE sequences
- P-V relationships
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging