Purpose: To evaluate the feasibility of spatially resolving the shear modulus of lung parenchyma using conventional 1H magnetic resonance elastography (MRE) imaging techniques in a small animal model. Materials and Methods: A 10-cm diameter transmit -receive radiofrequency coil was modified to include a specimen stage, an MRE pneumatic drum driver, and needle system. MRE was performed on 10 female Sprague-Dawley rats using a 1H spin-echo based MRE imaging sequence with a field of view of 7 cm and slice thickness of 5 mm. Air-filled lungs were imaged at transpulmonary inflation pressures of 5, 10, and 15 cm H 2O while fluid-filled lungs were imaged after infusion of 4 mL of normal saline. Results: The average shear modulus of air-filled lungs was 0.840 ± 0.0524 kPa, 1.07 ± 0.114 kPa and 1.30 ± 0.118 kPa at 5, 10, and 15 cm H 2O, respectively. Analysis of variance indicated that these population means were statistically significantly different from one another (F-value = 26.279, P = 0.00004). The shear modulus of the fluid-filled lungs was 1.65 ± 0.360 kPa. Conclusion: It is feasible to perform lung MRE in small animals using conventional MR imaging technologies.
- Magnetic resonance elastography
- Shear modulus
- Transpulmonary pressure
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging