Durst Markus, Koellisch Ulrich, Gringeri Concetta, Janich Martin A, Rancan Giaime, Frank Annette, Wiesinger Florian, Menzel Marion I, Haase Axel, Schulte Rolf F
Department of Medical Engineering, Technische Universität München, Boltzmannstrasse 11, 85748 Garching, Germany; GE Global Research, Freisinger Landstrasse 50, 85748 Garching, Germany.
Department of Medical Engineering, Technische Universität München, Boltzmannstrasse 11, 85748 Garching, Germany; GE Global Research, Freisinger Landstrasse 50, 85748 Garching, Germany.
J Magn Reson. 2014 Jun;243:40-6. doi: 10.1016/j.jmr.2014.02.011. Epub 2014 Mar 24.
Dynamic nuclear polarisation has enabled real-time metabolic imaging of pyruvate and its metabolites. Conventional imaging sequences rely on predefined settings and do not account for intersubject variations in biological parameters such as perfusion. We present a fully automatic real-time bolus tracking sequence for hyperpolarised substrates which starts the imaging acquisition at a defined point on the bolus curve. This reduces artefacts due to signal change and allows for a more efficient use of hyperpolarised magnetisation. For single time point imaging methods, bolus tracking enables a more reliable and consistent quantification of metabolic activity. An RF excitation with a small flip angle is used to obtain slice-selective pyruvate tracking information in rats. Moreover, in combination with a copolarised urea and pyruvate injection, spectrally selective tracking on urea allows obtaining localised bolus tracking information without depleting the pyruvate signal. Particularly with regard to clinical application, the bolus tracking technique could provide an important step towards a routine assessment protocol which removes operator dependencies and ensures comparable results.
动态核极化技术已实现对丙酮酸及其代谢物的实时代谢成像。传统成像序列依赖于预定义设置，并未考虑诸如灌注等生物学参数的个体间差异。我们提出了一种用于超极化底物的全自动实时团注追踪序列，该序列在团注曲线的定义点开始成像采集。这减少了由于信号变化导致的伪影，并允许更有效地利用超极化磁化。对于单时间点成像方法，团注追踪能够更可靠且一致地量化代谢活性。使用小翻转角的射频激发来获取大鼠切片选择性丙酮酸追踪信息。此外，结合共极化尿素和丙酮酸注射，对尿素进行光谱选择性追踪可在不消耗丙酮酸信号的情况下获得局部团注追踪信息。特别是在临床应用方面，团注追踪技术可能是迈向常规评估方案的重要一步，该方案可消除对操作者的依赖并确保结果具有可比性。
