DIRECTIONALLY ENCODED COLORMAPS FOR ANALYZING HUMAN BRAIN DIFFUSION TENSOR MRI

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心，不一定是研究者所在机构。导论.扩散张量磁共振成像（DTMRI）越来越多地用于评估各种病理患者的白色物质完整性。迹线和FA图显示了平均体积扩散率和结构组织水平，但两张图都没有显示潜在的各向异性。张量模式（TM）表征了从线性各向异性到平面各向异性的各向异性的种类，并且可以被并入到新颖的方向编码色图（DEC）中。方法. DTMRI图像在常规临床检查中在GE 1.5T扫描仪上获得。所有患者提供签署的知情同意书。使用弥散加权、切片交错、自旋回波平面成像序列采集图像。通过将主特征向量的分量编码到彩色图像的红色、绿色和蓝色通道中，然后通过FA和模式的乘积使颜色强度贬值，来生成包含模式的德克斯（DECM）。结果第一个病人在以前切除的GBM区域出现肿瘤浸润和水肿。DEC图表明外囊后部是一条连续的纤维轨迹，但DECM图表明该路径可能被中断。第二例患者表现为GBM和周围血管源性水肿。DEC图显示外囊周围的组织为一个大的纤维团，但DECM图清楚地描绘出一个较小的线性各向异性结构带。

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. Introduction. Diffusion tensor magnetic resonance imaging (DTMRI) is increasingly used to assess the white matter integrity of patients with a variety of pathologies. Trace and FA maps indicate the mean bulk diffusivity and the level of structural organization, but neither map indicates the kind of underlying anisotropy. Tensor mode (TM) characterizes the kind of anisotropy as it ranges from linear anisotropic to planar anisotropic and can be incorporated into novel directionally encoded colormaps (DEC). Methods. DTMRI images were acquired on a GE 1.5T scanner during a routine clinical exam. All patients provided signed statements of informed consent. A diffusion weighted, slice-interleaved, spin echo-planar imaging sequence was used to acquire images. DECs that incorporate mode (DECM) were generated by encoding the components of the primary eigenvector into the red, green, and blue channels of a color image, then devaluating the color intensity by the product of FA and mode. Results. The first patient presented with neoplastic infiltration and edema in the area of a previously resected GBM. DEC maps indicates that the posterior part of the external capsule is a continuous fiber track, but DECM maps indicates that this path is likely disrupted. The second patient presented with GBM and surrounding vasogenic edema. The tissue surrounding the external capsule a DEC map appears as a large fibrous mass, but the DECM map clearly delineates a smaller band of linear anisotropic structure.