Colon-Perez Luis M, King Michael, Parekh Mansi, Boutzoukas Angelique, Carmona Eduardo, Couret Michelle, Klassen Rosemary, Mareci Thomas H, Carney Paul R
Department of Biochemistry and Molecular Biology, University of Florida, Gainesville, FL, USA ; Department of Psychiatry, University of Florida, Gainesville, FL, USA.
Department of Pharmacology and Therapeutics, University of Florida, Gainesville, FL, USA ; Department of Veterans Affairs Medical Center, Gainesville, FL, USA.
Neuroimage Clin. 2015 Aug 1;9:58-68. doi: 10.1016/j.nicl.2015.07.005. eCollection 2015.
Emerging high-field diffusion weighted MR imaging protocols, along with tractography, can elucidate microstructural changes associated with brain disease at the sub-millimeter image resolution. Epilepsy and other neurological disorders are accompanied by structural changes in the hippocampal formation and associated regions; however, these changes can be subtle and on a much smaller scale than the spatial resolution commonly obtained by current clinical magnetic resonance (MR) protocols in vivo.
We explored the possibility of studying the organization of fresh tissue with a 17.6 Tesla magnet using diffusion MR imaging and tractography. The mesoscale organization of the temporal lobe was estimated using a fresh unfixed specimen obtained from a subject who underwent anterior temporal lobectomy for medically refractory temporal lobe epilepsy (TLE). Following ex vivo imaging, the tissue was fixed, serial-sectioned, and stained for correlation with imaging.
We resolved tissue microstructural organizational features in the temporal lobe from diffusion MR imaging and tractography in fresh tissue.
Fresh ex vivo MR imaging, along with tractography, revealed complex intra-temporal structural variation corresponding to neuronal cell body layers, dendritic fields, and axonal projection systems evident histologically. This is the first study to describe in detail the human temporal lobe structural organization using high-field MR imaging and tractography. By preserving the 3-dimensional structures of the hippocampus and surrounding structures, specific changes in anatomy may inform us about the changes that occur in TLE in relation to the disease process and structural underpinnings in epilepsy-related memory dysfunction.
新兴的高场扩散加权磁共振成像协议，连同纤维束成像，能够在亚毫米图像分辨率下阐明与脑部疾病相关的微观结构变化。癫痫和其他神经系统疾病伴随着海马结构及相关区域的结构变化；然而，这些变化可能很细微，且比当前临床磁共振（MR）协议在体内通常获得的空间分辨率小得多。
我们探讨了使用17.6特斯拉磁体通过扩散磁共振成像和纤维束成像研究新鲜组织结构的可能性。使用从一名因药物难治性颞叶癫痫（TLE）接受前颞叶切除术的受试者获取的新鲜未固定标本，估计颞叶的中尺度结构。在体外成像后，将组织固定、连续切片并染色以与成像结果进行对比。
我们通过新鲜组织的扩散磁共振成像和纤维束成像解析了颞叶的组织微观结构特征。
新鲜离体磁共振成像连同纤维束成像揭示了与神经元细胞体层、树突场和轴突投射系统相对应的复杂颞内结构变化，这些在组织学上是明显的。这是第一项使用高场磁共振成像和纤维束成像详细描述人类颞叶结构组织的研究。通过保留海马体及周围结构的三维结构，特定的解剖学变化可能会让我们了解在TLE中与疾病进程及癫痫相关记忆功能障碍的结构基础有关的变化。
