Ritt Philipp, Kuwert Torsten
Clinic of Nuclear Medicine, University Hospital Erlangen, Ulmenweg 18, 91054, Erlangen, Germany.
Recent Results Cancer Res. 2020;216:565-590. doi: 10.1007/978-3-030-42618-7_17.
The continuous development of SPECT over the past 50 years has led to improved image quality and increased diagnostic confidence. The most influential developments include the realization of hybrid SPECT/CT devices, as well as the implementation of attenuation correction and iterative image reconstruction techniques. These developments have led to a preference for SPECT/CT devices over SPECT-only systems and to the widespread adoption of the former, strengthening the role of SPECT/CT as the workhorse of Nuclear Medicine imaging. New trends in the ongoing development of SPECT/CT are diverse. For example, whole-body SPECT/CT images, consisting of acquisitions from multiple consecutive bed positions in the manner of PET/CT, are increasingly performed. Additionally, in recent years, some interesting approaches in detector technology have found their way into commercial products. For example, some SPECT cameras dedicated to specific organs employ semiconductor detectors made of cadmium telluride or cadmium zinc telluride, which have been shown to increase the obtainable image quality by offering a higher sensitivity and energy resolution. However, the advent of quantitative SPECT/CT which, like PET, can quantify the amount of tracer in terms of Bq/mL or as a standardized uptake value could be regarded as most important development. It is a major innovation that will lead to increased diagnostic accuracy and confidence, especially in longitudinal studies and in the monitoring of treatment response. The current work comprises two main aspects. At first, physical and technical fundamentals of SPECT image formation are described and necessary prerequisites of quantitative SPECT/CT are reviewed. Additionally, the typically achievable quantitative accuracy based on reports from the literature is given. Second, an extensive list of studies reporting on clinical applications of quantitative SPECT/CT is provided and reviewed.
在过去50年里，单光子发射计算机断层扫描（SPECT）的持续发展带来了图像质量的提升以及诊断信心的增强。最具影响力的发展包括混合型SPECT/CT设备的实现，以及衰减校正和迭代图像重建技术的应用。这些发展使得SPECT/CT设备相较于单纯的SPECT系统更受青睐，并得到广泛采用，强化了SPECT/CT作为核医学成像主力军的作用。SPECT/CT持续发展的新趋势多种多样。例如，越来越多地进行全身SPECT/CT图像采集，其方式类似于PET/CT，即从多个连续的床位位置进行采集。此外，近年来，探测器技术的一些有趣方法已应用于商业产品。例如，一些专门用于特定器官的SPECT相机采用碲化镉或碲锌镉制成的半导体探测器，这些探测器已被证明通过提供更高的灵敏度和能量分辨率来提高可获得的图像质量。然而，定量SPECT/CT的出现可被视为最重要的发展，它像PET一样，能够以贝克勒尔/毫升（Bq/mL）或标准化摄取值来量化示踪剂的量。这是一项重大创新，将提高诊断准确性和信心，尤其是在纵向研究和治疗反应监测方面。当前的工作包括两个主要方面。首先，描述了SPECT图像形成的物理和技术基础，并回顾了定量SPECT/CT的必要前提条件。此外，还给出了基于文献报道的典型可实现定量精度。其次，提供并回顾了大量关于定量SPECT/CT临床应用的研究列表。
