死后计算断层扫描中的图像渲染技术：受困鲸目动物的生物健康和特征评估
Summary
香港鲸目动物搁浅反应计划纳入了验尸计算机断层扫描，提供有关死亡动物的生物健康和档案的宝贵资料。这项研究描述了8种图像渲染技术，这些技术对于识别和可视化搁浅鲸目动物的验尸发现至关重要，这将有助于全世界的临床医生、兽医和绞尽脑，充分利用放射性模式。
Abstract
在香港鲸目动物绞线反应计划、标准化病毒贴顶程序、验尸计算机断层扫描（PMCT）采集、后处理和评估方面拥有6年的经验，成功建立。在这个首创的鲸目动物病毒搁浅反应计划，PMCT被执行193个搁浅鲸目动物，提供验尸发现，以帮助尸检和揭示动物的生物健康和配置文件。本研究旨在评估PMCT中的8种图像渲染技术，包括多平面重建、弯曲平面改造、最大强度投影、最小强度投影、直接体积渲染、分割、传输函数和透视体积渲染。这些技术以实际实例说明，能够识别搁浅鲸目动物中的大多数PM发现，并用作调查其生物健康和特征的工具。这项研究可以指导放射科医生、临床医生和兽医完成PMCT图像渲染和审查这一通常困难和复杂的领域。
Introduction
Virtopsy，也称为验尸（PM）成像，是检查具有高级横截面成像模式的尸体，包括验尸计算机断层扫描（PMCT）、死后磁共振成像（PMMRI）和超声成像1。在人类中，PMCT有助于调查骨骼改变,,,2、3、,3异体、气态发现4、5、6,5和血管系统7、8、9的病理的创伤性病例。68自2014年以来，病毒性病毒一直在香港鲸目动物搁浅反应计划1中实施。PMCT 和 PMMRI 能够描绘尸体的病理形态学发现，这些发现过于分解，无法通过常规尸检进行评估。非侵入性放射性评估是客观的，以数字方式进行，允许第二次意见或回顾性研究多年后1，10，11。,10,11Virtopsy已成为一种有价值的替代技术，为12、13、14、15、16,13,14,等搁浅海洋动物的PM发现提供新的见解。结合尸检，这是解释病理生理重建和死因的黄金标准17，可以解决动物的生物健康和特征。Virtopsy已逐渐得到认可，并在全球实施绞线应对计划，包括但不限于哥斯达黎加、日本、中国大陆、新西兰、台湾、泰国和美国1。
放射学中的图像渲染技术使用计算机算法将数字转换为有关组织的信息。例如，放射性密度用传统的X射线和CT表示。大量的体积数据以医学（DICOM）格式存储为数字成像和通信。CT图像可用于在后处理3D工作站中使用二维（2D）和三维（3D）图像渲染来生成等向异性体美数据，用于高分辨率可视化18，19。18,定量,数据和结果被映射，以将连续获得的轴向图像转换为具有灰度或颜色参数19、20、21,20的3D图像。从不同的渲染技术中选择适当的数据可视化方法是可视化质量的一个基本技术决定因素，它极大地影响了对放射性结果的分析和解释。对于涉及没有任何放射学背景的人员的绞线工作来说，这一点尤其重要，他们需要了解不同情况下的结果。实施这些图像渲染技术的目标是提高解剖细节、关系和临床发现可视化的质量，从而提升成像的诊断价值，并允许有效再现感兴趣的目标区域17、19、22、23、24、25。,19,22,23,24,25
虽然主轴向CT/MRI图像包含大多数信息，但它们可能限制对病理的准确诊断或记录，因为各种正交平面上无法查看结构。其他解剖学对齐平面的图像转换允许从另一个角度可视化结构关系，而不必重新定位身体26。由于医学解剖学和法医病理学数据主要是3D性质，彩色编码PMCT图像和3D重建图像优先于灰度图像和2D切片图像，因为提高可理解性和适合法庭裁决27，28。,28随着PMCT技术的进步，鲸目动物PM调查中对可视化探索（即2D和3D图像的创建和解释）的关注已经引起关注,。放射学工作站中的各种体积渲染技术使放射科医生、技术人员、转介临床医生（例如兽医和海洋哺乳动物科学家）甚至外行（例如绞线反应人员、政府官员和一般公众）能够可视化并研究感兴趣的区域。然而，选择适当的技术和术语的混淆仍然是一个主要问题。有必要了解常见技术的基本概念、优点和局限性，因为这将显著影响放射性发现诊断价值和解释。滥用技术可能会产生误导性的图像（例如，具有失真的图像、渲染错误、重建噪音或人工制品），并导致不正确的诊断 30。
本研究旨在评估 PMCT 中的 8 种基本图像渲染技术，这些技术用于鉴定香港水域搁浅鲸目动物中大部分 PM 的发现。提供了每种技术的描述和实际示例，以指导全世界的放射科医生、临床医生和兽医完成 PMCT 图像渲染和审查这一通常困难而复杂的领域，以评估生物健康和轮廓。
Protocol
Representative Results
Discussion
为了清晰可视化病毒数据集，通常将 8 种图像渲染技术（包括 2D 和 3D 渲染）应用于每个搁浅尸体，以调查其生物健康和轮廓。这些渲染技术包括 MPR、CPR、MIP、MinIP、DVR、分段、TF 和 PVR。不同的渲染技术与窗口调整一起得到补充使用。介绍了每种图像改造技术的概念和优点。
多平面重建
MPR 是创建非轴 2D 图像的过程，包括日冕、下垂和任何解剖对齐的斜平面图…
Disclosures
The authors have nothing to disclose.
Acknowledgements
作者感谢香港特别行政区政府渔农自然护理署对这项工程的持续支持。此外，我们亦衷心感谢来自香港城市大学水生动物病毒实验室、香港海洋公园保育基金会及香港海洋公园的兽医、职员及志愿者，为这项工程的搁浅反应付出巨大努力。特别感谢市大学兽医医疗中心和香港兽医影像中心的技术人员，他们负责进行本研究的CT和MRI单位。此处表达的任何意见、结论、结论或建议，并不一定反映海洋生态改善基金或受托人的意见。该项目由香港研究资助局（资助编号：UGC/FDS17/M07/14）及海洋生态改善基金（资助编号：MEEF2017014、MEEF2017014A、MEEF2019010及 MEEF2019010A）、海洋生态改善基金、海洋生态及渔业增强基金受托人有限公司资助。特别感谢玛丽亚·何塞·罗伯斯·马拉贡巴博士对这份手稿进行英文编辑。
Materials
| Aquarius iNtuition workstation | TeraRecon Inc | NA | |
| Siemens 64-row multi-slice spiral CT scanner Somatom go.Up | Siemens Healthineers | NA |
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