Toga A W, Ambach K, Quinn B, Hutchin M, Burton J S
Department of Neurology, UCLA School of Medicine 90024-1769.
J Neurosci Methods. 1994 Oct;54(2):239-52. doi: 10.1016/0165-0270(94)90196-1.
A system of histologic and digital processing protocols are presented for the acquisition of high-resolution digital imagery from postmortem cryosectioned whole human brain and head for computer-based 3-dimensional (3D) representation and visualization. We designed and evaluated several protocols for optimal preparation of frozen specimens including fixation, decalcification, cryoprotection, freezing and sectioning procedures. High-resolution (1024(2) pixel) serial images were captured directly from the cryoplaned blockface using an integrated color digital camera and fiber optic illumination system mounted over a modified cryomacrotome. Specimens frozen and sectioned with the cranium intact preserved brain spatial relationships and anatomic bony landmarks. Color preservation was superior in unfixed tissue heads were incompatible with decalcification and cryoprotection procedures and section collection from such specimens was complicated by bone fragmentation. Collection of 1024(2) images from whole brain resulted in a spatial resolution of 200 microns/pixel in a 1-3 Gbyte data space. Even higher 3D spatial resolution was possible by primary image capture of selected regions such as hippocampus or brain stem. Discrete registration errors were corrected using image processing strategies such as cross-correlative and other algorithmic approaches. Data sets were amenable to resampling in multiple planes as well as scaling and transpositioning into standard coordinate systems. These methods enable quantitative measurements for comparison between subjects and to published atlas data. These techniques allow visualization and measurement at resolutions far higher than those available through other imaging technologies and provide greatly enhanced contrast for delineation of neuroanatomic structures, pathways, and subregions.
本文介绍了一种组织学和数字处理协议系统,用于从死后冷冻切片的整个人脑和头部获取高分辨率数字图像,以进行基于计算机的三维(3D)呈现和可视化。我们设计并评估了几种用于冷冻标本最佳制备的协议,包括固定、脱钙、冷冻保护、冷冻和切片程序。使用安装在改良低温切片机上的集成彩色数码相机和光纤照明系统,直接从冷冻切片的标本块表面捕获高分辨率(1024×1024像素)系列图像。颅骨完整冷冻并切片的标本保留了脑的空间关系和解剖学骨标志。未固定组织中的颜色保存更好,而与脱钙和冷冻保护程序不兼容的头部标本的切片收集因骨碎片而变得复杂。从全脑收集1024×1024图像在1-3GB的数据空间中产生了200微米/像素的空间分辨率。通过对海马体或脑干等选定区域进行原始图像捕获,可以实现更高的3D空间分辨率。使用互相关等图像处理策略和其他算法方法校正离散配准误差。数据集适合在多个平面上重新采样,以及缩放和转换到标准坐标系。这些方法能够进行定量测量,以便在受试者之间进行比较,并与已发表的图谱数据进行比较。这些技术允许在远高于其他成像技术所能达到的分辨率下进行可视化和测量,并为描绘神经解剖结构、通路和子区域提供大大增强的对比度。