High-sensitivity cerebral perfusion mapping in mice by kbGRASE-FAIR at 9.4 T

The combination of flow-sensitive alternating inversion recovery (FAIR) and single-shot k-space-banded gradient- and spin-echo (kbGRASE) is proposed here to measure perfusion in the mouse brain with high sensitivity and stability. Signal-to-noise ratio (SNR) analysis showed that kbGRASE-FAIR boosts image and temporal SNRs by 2.01±0.08 and 2.50±0.07 times, respectively, when compared with standard single-shot echo planar imaging (EPI)-FAIR implemented in our experimental systems, although the practically achievable spatial resolution was slightly reduced. The effects of varying physiological parameters on the precision and reproducibility of cerebral blood flow (CBF) measurements were studied following changes in anesthesia regime, capnia and body temperature. The functional MRI time courses with kbGRASE-FAIR showed a more stable response to 5% CO₂ than did those with EPI-FAIR. The results establish kbGRASE-FAIR as a practical and robust protocol for quantitative CBF measurements in mice at 9.4T. The aim of this study was to develop a practical perfusion measurement with high sensitivity and stability in mouse brain at high field strength by the combination of flow-sensitive alternating inversion recovery (FAIR) and single-shot k-space-banded gradient- and spin-echo (kbGRASE). To estimate the influence of physiological parameters on the precision and reproducibility of cerebral blood flow (CBF) measurements, changes in anesthesia regime, capnia and body temperature were performed.