University of São Paulo, Faculty of Medicine, São Paulo, Brazil.
University of São Paulo, Faculty of Medicine, São Paulo, Brazil.
Epilepsy Behav. 2021 Aug;121(Pt B):106366. doi: 10.1016/j.yebeh.2019.06.010. Epub 2019 Jul 10.
Ultra-high field magnetic resonance imaging (UHF-MRI) is capable of unraveling anatomical structures in a submillimeter range. In addition, its high resonance regime allows the quantification of constitutive molecules in a spatially sensitive manner, a crucial capability for determining the extent and localization of a probable epileptogenic region or the severity of the epilepsy. The main technical challenges for data acquisition under UHF are to produce a strong, homogeneous transverse field, while keeping the tissue power deposition within the safe regulatory guidelines. The nonuniformities caused by destructive and constructive interferences at UHFs required new technologies to accelerate and increase yield regarding time spent and quality achieved. Image quality is the paramount contribution of UHF high-resolution imaging, which is capable to disclose fine details of the hippocampal formation and its surroundings and their changes in the course of epilepsy. Other sequences like diffusion tensor imaging (DTI) and multiecho susceptibility imaging at 7 T in vivo can assist the creation of normative atlases of the hippocampal subfields or the reconstruction of the highly arborized cerebral blood vessels. In our review, we specify the impact of these advanced relevant techniques onto the study of epilepsy. In this context, we focused onto high field high-resolution scanners and clinically-enriched decision-making. Studies on focal dysplasias correlating ex vivo high-resolution imaging with specific histological and ultrastructural patterns showed that white matter hyperintensities were related to a demyelination process and other alterations. Preliminary results correlating thick serial sections through bioptic epileptogenic tissue could extend the strategy to localize degenerated tissue sectors, correlate nature and extent of tissue loss with preoperative diagnosis and postoperative outcome. Finally, this protocol will provide the neurosurgeon with a detailed depiction of the removed pathologic tissue and possible adverse effects by the pathologic tissue left in situ. This article is part of the special issue "NEWroscience 2018".
超高磁场磁共振成像 (UHF-MRI) 能够在亚毫米范围内解开解剖结构。此外，其高共振状态允许以空间敏感的方式定量构成分子，这是确定可能的致痫区的范围和定位或癫痫严重程度的关键能力。在 UHF 下进行数据采集的主要技术挑战是产生强、均匀的横向场，同时将组织的功率沉积保持在安全的监管指南内。UHF 下的破坏性和建设性干扰引起的不均匀性需要新技术来加速和提高时间和质量的产量。图像质量是 UHF 高分辨率成像的主要贡献，它能够揭示海马体结构及其周围环境的细微细节及其在癫痫过程中的变化。其他序列，如活体 7T 下的扩散张量成像 (DTI) 和多回波磁化率成像，有助于创建海马子区的规范图谱或重建高度分枝的脑血管。在我们的综述中，我们具体说明了这些先进相关技术对癫痫研究的影响。在这方面，我们专注于高磁场高分辨率扫描仪和临床丰富的决策。将离体高分辨率成像与特定的组织学和超微结构模式相关联的局灶性发育不良研究表明，白质高信号与脱髓鞘过程和其他改变有关。通过生物癫痫组织的厚系列切片进行的初步结果可以扩展定位退变组织区域的策略，将组织损失的性质和程度与术前诊断和术后结果相关联。最后，该方案将为神经外科医生提供详细描述切除的病理性组织和可能由原位病理性组织引起的不良影响。本文是“NEWroscience 2018”特刊的一部分。
