Dynamic metabolic imaging of copolarized [2-13 C]pyruvate and [1,4-13 C2 ]fumarate using 3D-spiral CSI with alternate spectral band excitation.
Dynamic metabolic imaging of copolarized [2-13 C]pyruvate and [1,4-13 C2 ]fumarate using 3D-spiral CSI with alternate spectral band excitation.
复制标题
使用具有交替光谱带激发的 3D 螺旋 CSI 对共极化 [2-13 C] 丙酮酸盐和 [1,4-13 C2 ] 富马酸盐进行动态代谢成像。
DOI：
10.1002/mrm.27639
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发表时间：
2019
影响因子：
3.3
通讯作者：
Mayer,Dirk
中科院分区：
文献类型：
--
作者：
Singh,Maninder;Josan,Sonal;Zhu,Minjie;Jhajharia,Aditya;Mayer,Dirk
目的建立共极化[2 - 13 C]丙酮酸和[1，4 - 13 C2]富马酸盐，无化学位移伪影，也允许底物及其代谢产物的不同激发翻转角。MethodsThe建议的脉冲序列由2个频率选择性射频脉冲组成，交替激发2个光谱子带，每个子带后面是快速3D螺旋CSI（3D-spCSI）读数。光谱选择性射频脉冲被设计为在每个光谱子带中在基底和产物上激发差分翻转角。信号平均数的分析被用来确定一个光谱宽度适合解决在每个子bands.ResultsPhantom实验中使用的微分翻转角后，共极化策略和射频脉冲设计验证了感兴趣的代谢物。每个子带中谐振的信号行为不受相应交替频带的激励的影响。动态3D 13 C CSI数据证明了该序列能够同时成像代谢物如丙酮酸-水合物、乳酸、丙氨酸、富马酸和苹果酸，并检测四氯化碳诱导的肝损伤大鼠模型中肝脏的代谢变化。4 - 13 C2]富马酸盐，无化学位移伪影，同时还允许对底物和产物信号使用不同的翻转角。该方法对于炎症和细胞坏死的组合体内成像是潜在有用的。
PurposeDeveloping a method for simultaneous metabolic imaging of copolarized [2‐13C]pyruvate and [1,4‐13C2]fumarate without chemical shift displacement artifacts that also permits different excitation flip angles for substrates and their metabolic products.MethodsThe proposed pulse sequence consists of 2 frequency‐selective radiofrequency pulses to alternatingly excite 2 spectral sub‐bands each one followed by a fast 3D spiral CSI (3D‐spCSI) readout. Spectrally selective radiofrequency pulses were designed to excite differential flip angles on substrates and products in each spectral sub‐band. Number of signal averages analysis was used to determine a spectral width suitable to resolve the metabolites of interest in each of the sub‐bands.ResultsPhantom experiments verified the copolarization strategy and radiofrequency pulse design following differential flip angle used in our method. The signal behavior of the resonances in each sub‐band was unaffected by the excitation of the respective alternate frequency band. Dynamic 3D13C CSI data demonstrated the ability of the sequence to image metabolites like pyruvate‐hydrate, lactate, alanine, fumarate, and malate simultaneously and detect metabolic changes in the liver in a rat model of carbon tetrachloride‐induced liver damage.ConclusionThe presented method allows the dynamic CSI of a mixture of [2‐13C]pyruvate and [1,4‐13C2]fumarate without chemical shift displacement artifacts while also permitting the use of different flip angles for substrate and product signals. The method is potentially useful for combined in vivo imaging of inflammation and cell necrosis.