SPATIAL RESOLUTION DEPEND OF DTI TRACTOGRAPHY IN HUMAN OCCIPITO-CALLOSAL REGION

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 枕-胼胝体区DTI纤维束成像的空间分辨率依赖性 扩散张量成像（DTI）和纤维跟踪已被用于以非侵入性方式测量人体内的纤维结构连接。然而，低灵敏度是这些方法的主要限制，导致大量可能缺失的纤维束（FT）。在这里，我们研究了空间分辨率如何影响光纤跟踪的灵敏度，通过重新缩放数据到不同的分辨率。我们的数据表明，与上视野（upVF）相比，空间分辨率可以改变下视野（loVF）中的非对称交叉胼胝体连接的程度。在来自loVF的连接中，较大的体素大小导致与种子点数量不相称的较少数量的FT，而来自upVF的连接数量不受种子点数量变化的显著影响。我们的结论是，从我们的研究中所获得的数据的空间分辨率将不得不考虑在解释DTI纤维跟踪数据。我们的研究结果进一步表明，在常规DTI方案中，约2 mm等体素的采集分辨率可以重建枕胼胝体区不对称的上下白色结构。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Spatial resolution dependence of DTI tractography in human occipito-callosal region Diffusion tensor imaging (DTI) and fiber tracking have been used to measure the fiber structural connectivity in humans in a non-invasive manner. However, low sensitivity is a principal limitation of these methods, causing a large number of possibly missing fiber tracts (FTs). Here we studied how the spatial resolution affects the sensitivity of the fiber tracing by rescaling data to different resolutions. Our data suggest that the spatial resolution can change the degree of the asymmetric cross-callosal connections in the lower visual field (loVF) compared to the upper visual field (upVF). Among connections from loVF, a larger voxel size resulted in a smaller number of FTs that was not commensurate to the number of seed points, while the number of connections from upVF was not significantly affected by variation in seeding point numbers. We conclude from our study that the spatial resolution of the acquired data will have to be taken into consideration in interpreting DTI fiber tracking data. Our results further suggest that the acquisition resolution of around 2 mm iso-voxel in the conventional DTI scheme can reconstruct the asymmetric upper and lower white matter structure in occipito-callosal region.