High-resolution three-dimensional magnetic resonance imaging of mouse lung in situ.
OBJECTIVE
This study establishes a method for high-resolution isotropic magnetic resonance (MR) imaging of mouse lungs using tracheal liquid-instillation to remove MR susceptibility artifacts.


METHODS
C57BL/6J mice were instilled sequentially with perfluorocarbon and phosphate-buffered saline to an airway pressure of 10, 20, or 30 cm H2O. Imaging was performed in a 7T MR scanner using a 2.5-cm Quadrature volume coil and a 3-dimensional (3D) FLASH imaging sequence.


RESULTS
Liquid-instillation removed magnetic susceptibility artifacts and allowed lung structure to be viewed at an isotropic resolution of 78-90 microm. Instilled liquid and modeled lung volumes were well correlated (R = 0.92; P < 0.05) and differed by a constant tissue volume (220 +/- 92 microL). 3D image renderings allowed differences in structural dimensions (volumes and areas) to be accurately measured at each inflation pressure.


CONCLUSIONS
These data demonstrate the efficacy of pulmonary liquid instillation for in situ high-resolution MR imaging of mouse lungs for accurate measurement of pulmonary airway, parenchymal, and vascular structures.
Scadeng
Miriam
M
Department of Radiology, Center for Functional Magnetic Resonance Imaging, University of California, San Diego, La Jolla, California 92093, USA.
Rossiter
Harry B
HB
Dubowitz
David J
DJ
Breen
Ellen C
EC
D000704:Analysis of Variance; D000818:Animals; D016477:Artifacts; D003287:Contrast Media; D005466:Fluorocarbons / Q000008:administration & dosage; D019786:Gadolinium DTPA; D007089:Image Enhancement / Q000379:methods; D021621:Imaging, Three-Dimensional; D008168:Lung / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D051379:Mice; D008810:Mice, Inbred C57BL; D012965:Sodium Chloride / Q000008:administration & dosage
D003287:Contrast Media; D005466:Fluorocarbons; D012965:Sodium Chloride; D019786:Gadolinium DTPA