Chemical exchange saturation transfer MRI in central nervous system tumours on a 1.5 T MR-Linac
Chemical exchange saturation transfer MRI in central nervous system tumours on a 1.5 T MR-Linac
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DOI：
10.1016/j.radonc.2021.07.010
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发表时间：
2021-07-28
影响因子：
5.7
通讯作者：
Lau, Angus Z.
中科院分区：
文献类型：
--
作者：
Chan, Rachel W.;Lawrence, Liam S. P.;Lau, Angus Z.
目的：描述使用化学交换饱和转移 (CEST) 监测使用 1.5 特斯拉 MR 引导放射治疗系统治疗的中枢神经系统 (CNS) 肿瘤患者的实施情况和初步结果。方法：使用 1.5 T Elekta Unity MR-Linac 对 CNS 患者进行多达 30 次治疗（总剂量高达 60 Gy）。 54 名受试者在治疗期间的一个或多个时间点获得了 CEST 扫描。 CEST 指标，包括酰胺磁化转移比 (MTRAmide)、核奥弗豪瑟效应 (NOE) MTR (MTRNOE) 和不对称性，在体模和 CNS 患者中进行了量化。研究了肿瘤和白质之间、跨时间、跨疾病类别（包括高级别和低级别肿瘤）之间的信号。结果：与对侧正常白质相比，总肿瘤体积（GTV）表现出较低的 MTRAmide 和 MTRNOE 以及较高的不对称性。观察分次放疗期间 GTV 信号的变化。高级别和低级别肿瘤之间存在差异，CEST 不对称性越高，疾病级别越高。结论：使用 1.5 T MR-Linac 的 CEST MRI 被证明对于 CNS 肿瘤的体内成像是可行的。 CEST 图像显示肿瘤/白质对比度、时间 CEST 信号变化以及与肿瘤分级的关联。这些结果显示了使用代谢成像为自适应放射治疗方案的设计提供信息的最终目标的希望。 (C) 2021 作者。由 Elsevier B.V. 出版
Purpose: To describe the implementation and initial results of using Chemical Exchange Saturation Transfer (CEST) for monitoring patients with central nervous system (CNS) tumours treated using a 1.5 tesla MR-guided radiotherapy system.Methods: CNS patients were treated with up to 30 fractions (total dose up to 60 Gy) using a 1.5 T Elekta Unity MR-Linac. CEST scans were obtained in 54 subjects at one or more time points during treatment. CEST metrics, including the amide magnetization transfer ratio (MTRAmide), nuclear Overhauser effect (NOE) MTR (MTRNOE) and asymmetry, were quantified in phantoms and CNS patients. The signal was investigated between tumour and white matter, across time, and across disease categories including high- and low-grade tumours.Results: The gross tumour volume (GTV) exhibited lower MTRAmide and MTRNOE and higher asymmetry compared to contralateral normal appearing white matter. Signal changes in the GTV during fractionated radiotherapy were observed. There were differences between high- and low-grade tumours, with higher CEST asymmetry associated with higher grade disease.Conclusion: CEST MRI using a 1.5 T MR-Linac was demonstrated to be feasible for in vivo imaging of CNS tumours. CEST images showed tumour/white-matter contrast, temporal CEST signal changes, and associations with tumour grade. These results show promise for the eventual goal of using metabolic imaging to inform the design of adaptive radiotherapy protocols. (C) 2021 The Author(s). Published by Elsevier B.V.