Biomedical Imaging Lab, Agency for Science Technology and Research, 30 Biopolis Street, #07-01 Matrix, Singapore, 138671, Singapore.
Neuroinformatics. 2012 Jan;10(1):33-55. doi: 10.1007/s12021-011-9118-x.
We present a human brain atlas of white matter (WM) tracts containing 40 major tracts, which is three-dimensional (3D), segmented, labeled, interactive, stereotactic and correlated to structure and vasculature. We consider: (1) WM accuracy by correlating WM tracts to underlying neuroanatomy and quantifying them; (2) balance between realism and completeness by processing a sequence of track volumes generated for various parameters with the increasing track number to enable a tract "shape convergence". MPRAGE and DTI in 64 directions of the same subject were acquired on 3 Tesla. The method has three steps: DTI-MPRAGE registration, 3D tract generation from DTI, to WM reconstruction from MPRAGE to parcellation into 17 components. 82 track volumes were generated for a wide spectrum of parameter values: Fractional Anisotropy threshold in [0.0125, 0.55] and trajectory angle lower than 45°, 60°, 65°, 70°, 75°, 80°, 85°, 90°. For each tract, a sequence of track volumes was processed to create/edit contours delineating this tract to achieve its shape convergence. The parcellated tracts were grouped into commissures, associations, projections and posterior fossa tracts, and labeled following Terminologia Anatomica. To facilitate that, a dedicated tract editor is developed which processes multiple track volumes, handles tracts in three representations (tracks, contours, envelopes); provides editing/visualization simultaneously on axial, coronal, sagittal planes; enables tract labeling and coloring; and provides numerous tools (track counting, smoothing and length thresholding; representation conversion and saving; structural atlas support). A stereotactic tract atlas along with parcellated WM was developed to explore in real-time any individual tract or their groups along with surrounding neuroanatomy.
我们呈现了一个包含 40 条主要束的人脑白质（WM）束图谱，它是三维的、分割的、标记的、交互式的、立体定向的，并与结构和血管相关联。我们考虑了以下几点：（1）通过将 WM 束与基础神经解剖结构相关联并对其进行量化，来评估 WM 的准确性；（2）通过处理一系列针对不同参数生成的轨迹体积，平衡真实性和完整性，随着轨迹数量的增加，实现轨迹“形状收敛”。在 3 Tesla 上对同一受试者进行了 MPRAGE 和 DTI 采集，共 64 个方向。该方法有三个步骤：DTI-MPRAGE 配准、从 DTI 生成 3D 束、从 MPRAGE 重建 WM 并将其分割成 17 个成分。为了广泛的参数值范围，生成了 82 个轨迹体积：分数各向异性阈值在[0.0125，0.55]之间，轨迹角度小于 45°、60°、65°、70°、75°、80°、85°、90°。对于每条束，处理一系列轨迹体积以创建/编辑轮廓来描绘这条束，以实现其形状收敛。分割后的束被分组为连合束、联合束、投射束和后颅窝束，并按照 Terminologia Anatomica 进行标记。为了方便这一点，开发了一个专用的束编辑器，它可以处理多个轨迹体积，以三种表示形式（轨迹、轮廓、包络）处理束；在轴位、冠状位和矢状位上同时进行编辑/可视化；支持束标记和着色；并提供了许多工具（轨迹计数、平滑和长度阈值处理；表示转换和保存；结构图谱支持）。开发了一个立体定向束图谱以及分割的 WM，以便实时探索任何个体束或它们的群组以及周围的神经解剖结构。
