Abstract 14838: Compressed-Sensing Accelerated, Dual-Contrast, Quantitative First-Pass Perfusion MRI of the Mouse Heart
Introduction: Quantitative myocardial blood flow (MBF) imaging in gene-modified mice may elucidate molecular mechanisms that underlie coronary vascular dysfunction. We developed and evaluated a compressed sensing (CS)-accelerated first-pass sequence for mice with a dual-contrast acquisition.
Methods: C57Bl/6 mice were imaged at 7T at rest (n = 6) and with vasodilators ATL313 (n = 6, 0.025 μg/g body weight) and Regadenoson (n = 6, 0.1 μg/g body weight). Using Regadenoson, mice were further imaged with doses of 0.01 (n = 5), 0.02 (n = 5) and 0.05 μg/g body weight (n = 5) to generate a dose-response curve. A dual-contrast saturation-recovery sequence with ky and time domain undersampling was used to acquire first-pass images. The dual-contrast sequence acquires one slice for the arterial input function, and another slice for the tissue function. The acceleration factors for the arterial input function and tissue function slices were 6 and 4, respectively. Other imaging parameters were: TE/TR = 1.2/2.1 ms, resolution = 200 μm2, matrix = 128 x 74-104 and flip angle = 150. A motion-compensated CS algorithm was used to reconstruct the undersampled images. Fermi function deconvolution quantified perfusion.
Results: Figure (A-C) shows example first-pass images from a mouse. Figure D shows perfusion in mice at rest and with vasodilators ATL313 (*p<0.05 vs. rest) and Regadenoson (*p<0.05 vs. rest). Figure E shows the dose-response curve for Regadenoson (*p<0.05 vs. rest, #p<0.05 vs. 0.01μg/g).
Conclusions: CS-accelerated first-pass MRI enables the quantification of MBF in the mouse heart over a wide range of flows. These methods promise to prove valuable in the assessment of key molecular mechanisms that underlie coronary vascular dysfunction.
- © 2013 by American Heart Association, Inc.