Department of Pediatrics, University Hospitals Leuven, UZ Leuven, Belgium.
Department of Radiology, University Hospitals Leuven, UZ Leuven, Belgium.
Hum Brain Mapp. 2018 Aug;39(8):3375-3387. doi: 10.1002/hbm.24082. Epub 2018 Apr 20.
With the increase of survival rates of pediatric cancer patients, the number of children facing potential cognitive sequelae has grown. Previous adult studies suggest that white matter (WM) microstructural changes may contribute to cognitive impairment. This study aims to investigate WM microstructure in childhood bone and soft tissue sarcoma. Differences in (micro-)structure can be investigated using diffusion MRI (dMRI). The typically used diffusion tensor model (DTI) assumes Gaussian diffusion, and lacks information about fiber populations. In this study, we compare WM structure of childhood bone and soft tissue sarcoma survivors (n = 34) and matched controls (n = 34), combining typical and advanced voxel-based models (DTI and NODDI model, respectively), as well as recently developed fixel-based models (for estimations of intra-voxel differences, apparent fiber density [AFD] and fiber cross-section [FC]). Parameters with significant findings were compared between treatments, and correlated with subscales of the WAIS-IV intelligence test, age at diagnosis, age at assessment and time since diagnosis. We encountered extensive regions showing lower fractional anisotropy, overlapping with both significant NODDI parameters and fixel-based parameters. In contrast to these diffuse differences, the fixel-based measure of AFD was reduced in the cingulum and corpus callosum only. Furthermore, AFD of the corpus callosum was significantly predicted by chemotherapy treatment and correlated positively with time since diagnosis, visual puzzles and similarities task scores. This study suggests altered WM structure of childhood bone and soft tissue sarcoma survivors. We conclude global chemotherapy-related changes, with particular vulnerability of centrally located WM bundles. Finally, such differences could potentially recover after treatment.
随着儿科癌症患者生存率的提高，面临潜在认知后遗症的儿童人数不断增加。先前的成人研究表明，白质（WM）微观结构的变化可能导致认知障碍。本研究旨在研究儿童骨和软组织肉瘤中的 WM 微观结构。可以使用扩散 MRI（dMRI）研究（微观）结构的差异。通常使用的扩散张量模型（DTI）假设为高斯扩散，缺乏有关纤维群体的信息。在这项研究中，我们将儿童骨和软组织肉瘤幸存者（n=34）和匹配的对照组（n=34）的 WM 结构进行了比较，结合了典型和先进的体素基模型（分别为 DTI 和 NODDI 模型），以及最近开发的固定基模型（用于估计体素内差异，表观纤维密度[AFD]和纤维横截面[FC]）。对有显著发现的参数进行了治疗间比较，并与 WAIS-IV 智力测验的子量表、诊断时的年龄、评估时的年龄和诊断后时间进行了相关性分析。我们遇到了广泛的区域，这些区域的各向异性分数较低，与 NODDI 参数和固定基参数均有显著重叠。与这些弥漫性差异相反，固定基的 AFD 仅在扣带束和胼胝体中减少。此外，胼胝体的 AFD 与化疗治疗显著相关，与诊断后时间、视觉拼图和相似性任务得分呈正相关。本研究表明，儿童骨和软组织肉瘤幸存者的 WM 结构发生了改变。我们得出结论，存在与化疗相关的整体变化，而中央位置的 WM 束尤其脆弱。最后，这些差异在治疗后可能会恢复。
