Meng Yuguang, Lei Hao
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, 30# Xiaohongshan, 430071 Wuhan, Hubei, People's Republic of China.
MAGMA. 2009 Apr;22(2):135-42. doi: 10.1007/s10334-008-0157-8. Epub 2008 Dec 5.
To develop a continuous arterial spin labeling (CASL) perfusion imaging method for cerebral blood flow (CBF) measurement in rats with reduced spin-labeling length and optimized signal-to-noise ratio (SNR(f)) per unit time.
In the proposed method, the longitudinal magnetization of brain tissue water in the imaging slice is prepared into a proper state before spin-labeling, and a post-tagging delay is employed after spin-labeling. The method was implemented on a 4.7 T small animal scanner. Numerical simulations and in vivo experiments were used to evaluate the performance of the method proposed.
With the proposed method, absolute CBF could be measured accurately from normal rat with a spin-labeling pulse as short as 400 ms, and yet employing the same formula as that used in the conventional CASL perfusion imaging method for calculation. The method also showed improved SNR(f) per unit time over the conventional CASL perfusion imaging method and the pulsed arterial spin labeling perfusion imaging method FAIR.
Compared to the conventional CASL perfusion imaging method, the proposed method would be advantageous for CBF measurement in small animals having short vascular transit time in terms of SNR(f) per unit time and other benefits brought by shortened spin-labeling pulse.
开发一种连续动脉自旋标记（CASL）灌注成像方法，用于测量大鼠脑血流量（CBF），该方法具有缩短的自旋标记长度并优化了单位时间内的信噪比（SNR(f)）。
在所提出的方法中，成像切片中脑组织水的纵向磁化在自旋标记之前被制备成适当的状态，并且在自旋标记之后采用标记后延迟。该方法在4.7T小动物扫描仪上实现。使用数值模拟和体内实验来评估所提出方法的性能。
使用所提出的方法，对于正常大鼠，使用短至400ms的自旋标记脉冲就能准确测量绝对CBF，并且使用与传统CASL灌注成像方法相同的公式进行计算。该方法在单位时间内的SNR(f)也比传统CASL灌注成像方法和脉冲动脉自旋标记灌注成像方法FAIR有所提高。
与传统CASL灌注成像方法相比，所提出的方法在单位时间内的SNR(f)以及缩短自旋标记脉冲带来的其他益处方面，对于血管通过时间短的小动物的CBF测量将具有优势。
