Institute for Diagnostic and Interventional Radiology, University Medical Center Göttingen, Göttingen, Germany.
Department of Engineering and Architecture, University of Trieste, Trieste, Italy.
Mol Imaging Biol. 2018 Oct;20(5):732-741. doi: 10.1007/s11307-018-1246-3.
Histology and immunohistochemistry of thin tissue sections have been the standard diagnostic procedure in many diseases for decades. This method is highly specific for particular tissue regions or cells, but mechanical sectioning of the specimens is required, which destroys the sample in the process and can lead to non-uniform tissue deformations. In addition, regions of interest cannot be located beforehand and the analysis is intrinsically two-dimensional. Micro X-ray computed tomography (μCT) on the other hand can provide 3D images at high resolution and allows for quantification of tissue structures, as well as the localization of small regions of interest. These advantages advocate the use of μCT for virtual histology tool with or without subsequent classical histology. This review summarizes the most recent examples of virtual histology and provides currently known possibilities of improving contrast and resolution of μCT. Following a background in μCT imaging, ex vivo staining procedures for contrast enhancement are presented as well as label-free virtual histology approaches and the technologies, which could rapidly advance it, such as phase-contrast CT. Novel approaches such as zoom tomography and nanoparticulate contrast agents will also be considered. The current evidence suggests that virtual histology may present a valuable addition to the workflow of histological analysis, potentially reducing the workload in pathology, refining tissue classification, and supporting the detection of small malignancies.
几十年来，组织学和免疫组织化学的薄组织切片一直是许多疾病的标准诊断程序。这种方法对特定的组织区域或细胞具有高度特异性，但需要对标本进行机械切片，这会在切片过程中破坏样本，并导致组织变形不均匀。此外，无法事先定位感兴趣的区域，并且分析本质上是二维的。另一方面，微计算机断层扫描 (μCT) 可以提供高分辨率的 3D 图像，并允许对组织结构进行定量，以及定位小的感兴趣区域。这些优势主张使用 μCT 进行虚拟组织学工具，无论是带有还是不带有后续的经典组织学。这篇综述总结了最近的虚拟组织学实例，并提供了目前已知的提高 μCT 对比度和分辨率的可能性。在介绍 μCT 成像背景之后，还介绍了用于对比度增强的体外染色程序以及无标记的虚拟组织学方法，以及可能会迅速推进它的技术，如相衬 CT。还将考虑新的方法，如变焦断层扫描和纳米颗粒造影剂。目前的证据表明，虚拟组织学可能是组织学分析工作流程的一个有价值的补充，有可能减少病理学工作量，改进组织分类，并支持检测小的恶性肿瘤。
