Track density imaging (TDI): Validation of super resolution property
Track density imaging (TDI): Validation of super resolution property
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DOI：
10.1016/j.neuroimage.2011.02.059
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发表时间：
2011-06-01
期刊：
影响因子：
5.7
通讯作者：
Connelly, Alan
中科院分区：
文献类型：
--
作者：
Calamante, Fernando;Tournier, Jacques-Donald;Connelly, Alan
我们最近推出了一种新颖的 MRI 方法，即所谓的超分辨率磁道密度成像 (TDI)，它可以生成高质量的白质图像，具有其他 MRI 模式无法提供的高空间分辨率和精致的解剖对比度。该方法利用扩散 MRI 纤维轨迹中包含的长程信息实现超分辨率。在本研究中，我们通过使用在超高磁场强度 (7 T) 下采集的体内扩散 MRI 数据以及来自充分表征的数字模型的硅片扩散 MRI 数据来验证 TDI 方法的超分辨率特性。此外，还描述了 TDI 技术的替代版本，该技术减轻了 TDI 图强度的轨道长度加权。对于体内数据，对高分辨率扩散图像进行下采样以模拟低分辨率数据，其中高分辨率图像作为黄金标准。对于计算机数据，黄金标准是由数字模型的已知模拟结构给出的。体内和计算机数据均表明，只有使用超分辨率后才能在 TDI 图谱中识别的结构与参考图谱中识别的相应结构一致。这支持了超分辨率步骤识别的结构是准确的这一说法，从而为超分辨率 TDI 方法在神经科学中的重要潜在作用提供了进一步的证据。 (C) 2011 Elsevier Inc. 保留所有权利。
We have recently introduced a novel MRI methodology, so-called super resolution track-density imaging (TDI), which produces high-quality white matter images, with high spatial resolution and exquisite anatomical contrast not available from other MRI modalities. This method achieves super resolution by utilising the long-range information contained in the diffusion MRI fibre tracks. In this study, we validate the super resolution property of the TDI method by using in vivo diffusion MRI data acquired at ultra-high magnetic field strength (7 T), and in silico diffusion MRI data from a well-characterised numerical phantom. Furthermore, an alternative version of the TDI technique is described, which mitigates the track length weighting of the TDI map intensity. For the in vivo data, high-resolution diffusion images were down-sampled to simulate low-resolution data, for which the high-resolution images serve as a gold standard. For the in silico data, the gold standard is given by the known simulated structures of the numerical phantom. Both the in vivo and in silico data show that the structures that could be identified in the TDI maps only after using super resolution were consistent with the corresponding structures identified in the reference maps. This supports the claim that the structures identified by the super resolution step are accurate, thus providing further evidence for the important potential role of the super resolution TDI methodology in neuroscience. (C) 2011 Elsevier Inc. All rights reserved.