Miller Jack J, Lau Angus Z, Teh Irvin, Schneider Jürgen E, Kinchesh Paul, Smart Sean, Ball Vicky, Sibson Nicola R, Tyler Damian J
Department of Physics, Clarendon Laboratory, University of Oxford, England, UK.
Department of Physiology, Anatomy & Genetics, University of Oxford, England, UK.
Magn Reson Med. 2016 Apr;75(4):1515-24. doi: 10.1002/mrm.25730. Epub 2015 May 20.
Hyperpolarized metabolic imaging has the potential to revolutionize the diagnosis and management of diseases where metabolism is dysregulated, such as heart disease. We investigated the feasibility of imaging rodent myocardial metabolism at high resolution at 7 T.
We present here a fly-back spectral-spatial radiofrequency pulse that sidestepped maximum gradient strength requirements and enabled high resolution metabolic imaging of the rodent myocardium. A 3D echo-planar imaging readout followed, with centric ordered z-phase encoding. The cardiac gated sequence was used to image metabolism in rodents whose metabolic state had been manipulated by being fasted, fed, or fed and given the pyruvate dehydrogenase kinase inhibitor dichloroacetate.
We imaged hyperpolarized metabolites with a spatial resolution of 2×2×3.8 mm(3) and a temporal resolution of 1.8 s in the rat heart at 7 T. Significant differences in myocardial pyruvate dehydrogenase flux were observed between the three groups of animals, concomitant with the known biochemistry.
The proposed sequence was able to image in vivo metabolism with excellent spatial resolution in the rat heart. The field of view enabled the simultaneous multi-organ acquisition of metabolic information from the rat, which is of great utility for preclinical research in cardiovascular disease. Magnetic Resonance in Medicine published by Wiley Periodicals, Inc. on behalf of International Society for Magnetic Resonance.
超极化代谢成像有潜力彻底改变代谢失调疾病（如心脏病）的诊断和管理方式。我们研究了在7T磁场下对啮齿动物心肌代谢进行高分辨率成像的可行性。
我们在此展示了一种回波光谱空间射频脉冲，该脉冲规避了最大梯度强度要求，并实现了对啮齿动物心肌的高分辨率代谢成像。随后采用3D回波平面成像读出，并进行中心有序的z相位编码。心脏门控序列用于对代谢状态通过禁食、喂食或喂食并给予丙酮酸脱氢酶激酶抑制剂二氯乙酸进行操控的啮齿动物的代谢进行成像。
我们在7T磁场下对大鼠心脏中的超极化代谢物进行了成像，空间分辨率为2×2×3.8 mm³，时间分辨率为1.8秒。在三组动物之间观察到心肌丙酮酸脱氢酶通量存在显著差异，这与已知的生物化学情况相符。
所提出的序列能够在大鼠心脏中以优异的空间分辨率对体内代谢进行成像。该视野能够同时从大鼠身上多器官获取代谢信息，这对心血管疾病的临床前研究非常有用。《磁共振成像医学》由威利期刊公司代表国际磁共振学会出版。
