title: Feasibility of quantifying the mechanical properties of lung parenchyma in a small-animal model using (1)H magnetic resonance elastography (MRE).
abstract: OBJECTIVE
  To evaluate the feasibility of spatially resolving the shear modulus of lung parenchyma using conventional (1)H magnetic resonance elastography (MRE) imaging techniques in a small animal model.
  
  
  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 (1)H 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(2)O 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(2)O, 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.
  
  
  CONCLUSIONS
  It is feasible to perform lung MRE in small animals using conventional MR imaging technologies.
authors.affiliation: Department of Radiology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA. mcgee.kiaran@mayo.edu
authors.forename: Kiaran P
authors.initials: KP
authors.lastname: McGee
authors.forename: Rolf D
authors.initials: RD
authors.lastname: Hubmayr
authors.forename: David
authors.initials: D
authors.lastname: Levin
authors.forename: Richard L
authors.initials: RL
authors.lastname: Ehman
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D054459:Elasticity Imaging Techniques / Q000379:methods*; D004867:Equipment Design; D005240:Feasibility Studies; D005260:Female; D008168:Lung / Q000502:physiology*; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley