放射治疗是脑肿瘤患者的主要治疗方法。然而，它会导致认知障碍。为了改善辐射引起的脑后遗症的管理，基于变形的形态测量（DBM）可能是相关的。在这里，我们使用通过 MRI 图像非线性配准获得的雅可比行列式 (JD) 分析了 DBM 的重要性，以检测脑照射动物模型中健康脑组织的局部脆弱性。 大鼠接受分次全脑照射 (WBI) ，30 戈瑞）。 WBI 后 1 个月至 6 个月纵向进行多参数 MRI（解剖、弥散和血管）研究。根据 MRI 图像的配准，通过 DBM 分析宏观变化，并通过脑血量 (CBV) 的量化和包括平均扩散率 (MD) 在内的扩散指标来评估细胞和血管水平的微观变化。对整个大脑和 DBM 识别的特定大脑区域进行体素比较。进行免疫组织学分析以可视化血管和星形胶质细胞。DBM 分析证明了局部宏观结构变化的时间过程；其中一些是短暂的，一些是在WBI之后长期持续的。 DBM 揭示了两个脆弱的大脑区域，即胼胝体和皮质。 DBM 变化与微观结构变化在空间上相关，如扩散指标和 CBV 变化所揭示的那样，并通过免疫组织学分析得到证实。最后，矩阵相关性证明了 WBI 后早期 JD/MD 与胼胝体和皮质后期 JD/CBV 之间的相关性。脑照射引起 DBM 检测到的局部宏观结构变化，这可能与识别大脑结构有关容易发生辐射引起的组织变化。这些数据在患者身上的转化可以代表脑放射毒性成像研究的附加值。© 2024。作者。

Radiotherapy is a major therapeutic approach in patients with brain tumors. However, it leads to cognitive impairments. To improve the management of radiation-induced brain sequalae, deformation-based morphometry (DBM) could be relevant. Here, we analyzed the significance of DBM using Jacobian determinants (JD) obtained by non-linear registration of MRI images to detect local vulnerability of healthy cerebral tissue in an animal model of brain irradiation.Rats were exposed to fractionated whole-brain irradiation (WBI, 30 Gy). A multiparametric MRI (anatomical, diffusion and vascular) study was conducted longitudinally from 1 month up to 6 months after WBI. From the registration of MRI images, macroscopic changes were analyzed by DBM and microscopic changes at the cellular and vascular levels were evaluated by quantification of cerebral blood volume (CBV) and diffusion metrics including mean diffusivity (MD). Voxel-wise comparisons were performed on the entire brain and in specific brain areas identified by DBM. Immunohistology analyses were undertaken to visualize the vessels and astrocytes.DBM analysis evidenced time-course of local macrostructural changes; some of which were transient and some were long lasting after WBI. DBM revealed two vulnerable brain areas, namely the corpus callosum and the cortex. DBM changes were spatially associated to microstructural alterations as revealed by both diffusion metrics and CBV changes, and confirmed by immunohistology analyses. Finally, matrix correlations demonstrated correlations between JD/MD in the early phase after WBI and JD/CBV in the late phase both in the corpus callosum and the cortex.Brain irradiation induces local macrostructural changes detected by DBM which could be relevant to identify brain structures prone to radiation-induced tissue changes. The translation of these data in patients could represent an added value in imaging studies on brain radiotoxicity.© 2024. The Author(s).