Diffusion Atlas

# Fetal Diffusion Atlas Fetal diffusion atlas (reference below) with added tissue segmentations and regional parcellations. ## Contents This dataset contains diffusion atlas images for gestational age weeks 23 through 38. The diffusion atlas reconstructions were computed in separate coordinates as compared to the CRL2025 T2 atlas. These files are referred to as \"DWI-space\". To bring the two atlases in alignment we matched image direction header information of the DWI images to the T2 atlas, computed 3 degree-of-freedom translational shifts to overlay with the T2 atlas, and then manually edited the image headers to move the diffusion images into the correct space. The base diffusion atlas images are an improved version of the original DWI atlas (Khan et al. 2019) using the same set of subject tensor images. Tissue and regional segmentations were fitted to diffusion atlases using diffeomorphic registration of T2 atlas images to the diffusion atlas, and then modified by hand for research purposes and have been made available here. Segmentations for GA weeks 23-35 were previously available and carefully edited. For this release, automatically propagated segmentations for weeks 36-38 were added but have low quality. File suffixes: _tensor - Reconstructed tensor image Diffusion scalar images derived from tensor: _fa - Franctional anisotropy _cfa - Color FA _md - Mean diffusivity _tissue - Tissue segmentation _region - Regional segmentation DWIAtlas_labelkey.txt - ITK-SNAP label key for Tissue and Regional segmentations ## License/Data Use Agreement These files are published under CC BY 4.0: https://creativecommons.org/licenses/by/4.0/ Files in this data release were developed for research purposes and are not intended for medical or diagnostic use and have no warranty. The authors and distributors do not make any guarantees regarding the accuracy or usefulness of results generated from these tools or their derivatives, and are not liable for any damages resulting from their use. Through this data use agreement, you agree to cite the DOI referring to this resource as well as the following work: Bagheri, M., Velasco-Annis, C., Wang, J., Faghihpirayesh, R., Khan, S., Calixto, C., Jaimes, C., Vasung, L., Ouaalam, A., Afacan, O., Warfield, S.K., 2025, Rollins, C.K., and Gholipour A. An MRI Atlas of the Human Fetal Brain: Reference and Segmentation Tools for Fetal Brain MRI Analysis. arXiv preprint arXiv:2508.15034. Khan, S., Vasung, L., Marami, B., Rollins, C.K., Afacan, O., Ortinau, C.M., Yang, E., Warfield, S.K. and Gholipour, A., 2019. Fetal brain growth portrayed by a spatiotemporal diffusion tensor MRI atlas computed from in utero images. Neuroimage, 185, pp.593-608. Khan, S., Rollins, C.K., Ortinau, C.M., Afacan, O., Warfield, S.K. and Gholipour, A., 2018. Tract-specific group analysis in fetal cohorts using in utero diffusion tensor imaging. In Medical Image Computing and Computer Assisted Intervention–MICCAI 2018: 21st International Conference, Granada, Spain, September 16-20, 2018, Proceedings, Part III 11 (pp. 28-35). Springer International Publishing.

# 胎儿扩散图谱（Fetal Diffusion Atlas）：附带组织分割与区域分区的胎儿扩散图谱（详见下文）

## 数据集内容
本数据集包含孕龄23至38周的扩散图谱图像。
本数据集的扩散图谱重建与CRL2025 T2图谱采用不同坐标系计算，此类文件被称为「DWI空间（DWI-space）」。为使两类图谱对齐，研究人员将DWI图像的图像方向头文件信息与T2图谱匹配，计算3自由度平移偏移量以与T2图谱叠加，随后手动编辑图像头文件，将扩散图像调整至正确空间。
基础扩散图谱图像是原始DWI图谱（Khan等，2019）的改进版本，采用了同一组受试者张量图像。组织与区域分割通过将T2图谱图像微分同胚配准（diffeomorphic registration）至扩散图谱完成拟合，随后为研究需求手动修改，并在此处公开。
孕龄23至35周的分割结果此前已公开并经过精心编辑。本版本新增了孕龄36至38周的自动传播分割结果，但质量较低。

### 文件后缀说明
- `_tensor`：重建张量图像
- 由张量衍生的扩散标量图像：
- `_fa`：各向异性分数（Fractional Anisotropy，FA）
- `_cfa`：彩色各向异性分数
- `_md`：平均扩散率
- `_tissue`：组织分割结果
- `_region`：区域分割结果
- `DWIAtlas_labelkey.txt`：用于组织与区域分割的ITK-SNAP标签密钥文件

## 许可与数据使用协议
本文件采用CC BY 4.0协议发布：https://creativecommons.org/licenses/by/4.0/
本数据发布中的文件仅用于研究目的，不得用于医疗或诊断用途，且不提供任何担保。作者与分发者不对基于此类工具或其衍生工具生成结果的准确性与实用性作出任何保证，亦不对因使用此类工具导致的任何损害承担责任。
通过本数据使用协议，您同意引用本资源的DOI以及以下文献：
1. Bagheri, M., Velasco-Annis, C., Wang, J., Faghihpirayesh, R., Khan, S., Calixto, C., Jaimes, C., Vasung, L., Ouaalam, A., Afacan, O., Warfield, S.K., 2025, Rollins, C.K., and Gholipour A. 《人类胎儿脑MRI图谱：胎儿脑MRI分析的参考与分割工具》，arXiv预印本arXiv:2508.15034
2. Khan, S., Vasung, L., Marami, B., Rollins, C.K., Afacan, O., Ortinau, C.M., Yang, E., Warfield, S.K. and Gholipour, A., 2019. 《基于宫内图像构建的时空扩散张量MRI图谱展现胎儿脑发育》，*Neuroimage*，第185卷，第593-608页
3. Khan, S., Rollins, C.K., Ortinau, C.M., Afacan, O., Warfield, S.K. and Gholipour, A., 2018. 《基于宫内扩散张量成像的胎儿队列神经束特异性组分析》，收录于《医学图像计算与计算机辅助干预——MICCAI 2018：第21届国际会议论文集（第三部分，第11卷）》，西班牙格拉纳达，2018年9月16-20日，第28-35页，Springer International Publishing出版