T1- and T2*-dominant extravasation correction in DSC-MRI: Part I-theoretical considerations and implications for assessment of tumor hemodynamic properties
T1- and T2*-dominant extravasation correction in DSC-MRI: Part I-theoretical considerations and implications for assessment of tumor hemodynamic properties
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DOI：
10.1038/jcbfm.2011.52
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发表时间：
2011-10-01
影响因子：
6.3
通讯作者：
Emblem, Kyrre E.
中科院分区：
文献类型：
--
作者：
Bjornerud, Atle;Sorensen, A. Gregory;Emblem, Kyrre E.
我们提出了一种新的造影剂（CA）外渗校正方法的基础上分析的组织残留功能评估的多个血流动力学参数。该方法能够半定量测定的转移常数，并可用于区分T-1和T-2*-显性外渗效应，而不敏感的组织平均通过时间（MTT）的变化。101例确诊胶质瘤患者的结果表明，与标准化CBV值结合既定的渗漏校正方法相比，采用所提出的方法获得的渗漏校正绝对脑血容量（CBV）值提供了改善的总生存预测。使用标准梯度回波回波平面成像序列，类似于60%和10%的可检测CA外渗的肿瘤主要表现为T-1和T-2* 优势渗漏效应。其余30%的渗漏性肿瘤具有混合的T-1和T-2* 显性效应。使用MTT敏感的校正方法，我们的研究结果表明，CBV被低估时，肿瘤MTT显着长于MTT在参考组织。此外，从我们的模拟结果表明，T-1-与T-2*-占主导地位的外渗效应的相对贡献是强烈依赖于有效的横向弛豫在血管外空间，因此可能是一个潜在的标志物细胞的完整性和组织结构。Journal of Cerebral Blood Flow & Metabolism（2011）31，2041-2053; doi：10.1038/jcbfm.2011.52; 2011年4月20日在线发表
We present a novel contrast agent (CA) extravasation-correction method based on analysis of the tissue residue function for assessment of multiple hemodynamic parameters. The method enables semiquantitative determination of the transfer constant and can be used to distinguish between T-1- and T-2*-dominant extravasation effects, while being insensitive to variations in tissue mean transit time (MTT). Results in 101 patients with confirmed glioma suggest that leakage-corrected absolute cerebral blood volume (CBV) values obtained with the proposed method provide improved overall survival prediction compared with normalized CBV values combined with an established leakage-correction method. Using a standard gradient-echo echo-planar imaging sequence, similar to 60% and 10% of tumors with detectable CA extravasation mainly exhibited T-1- and T-2*-dominant leakage effects, respectively. The remaining 30% of leaky tumors had mixed T-1- and T-2*-dominant effects. Using an MTT-sensitive correction method, our results show that CBV is underestimated when tumor MTT is significantly longer than MTT in the reference tissue. Furthermore, results from our simulations suggest that the relative contribution of T-1-versus T-2*-dominant extravasation effects is strongly dependent on the effective transverse relaxivity in the extravascular space and may thus be a potential marker for cellular integrity and tissue structure. Journal of Cerebral Blood Flow & Metabolism (2011) 31, 2041-2053; doi:10.1038/jcbfm.2011.52; published online 20 April 2011