Filtering in SPECT Image Reconstruction.
Filtering in SPECT Image Reconstruction.
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DOI：
10.1155/2011/693795
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发表时间：
2011
影响因子：
7.6
通讯作者：
Ploussi A
中科院分区：
文献类型：
--
作者：
Lyra M;Ploussi A
单光子发射计算机断层扫描 (SPECT) 成像在核医学中广泛应用，因为它在多种疾病的诊断和治疗中的临床作用很多时候非常有帮助（例如心肌灌注成像）。 SPECT 图像的质量会因多种因素而降低，例如由于计数数量有限而产生的噪声、光子的衰减或散射。图像滤波对于补偿这些影响是必要的，因此可以提高图像质量。断层扫描图像中的滤波目标是抑制统计噪声，同时保持空间分辨率和对比度。这项工作的目的是描述 SPECT 应用中最广泛使用的滤波器以及它们如何影响图像质量。滤波器类型、截止频率和阶数的选择是临床常规中的一个主要问题。在许多临床案例中，没有提供特定参数的信息，并且研究结果不能外推到其他类似的 SPECT 成像应用。还提供了确定心脏、大脑、骨骼、肝脏、肾脏和甲状腺应用中最常用过滤器的文献综述。从概述中可以看出，没有任何过滤器是完美的，并且大多数时候，正确过滤器的选择是凭经验完成的。图像处理结果的标准化可能会将每次 SPECT 检查的滤波器类型限制为某些少数滤波器及其某些参数。标准化还有助于减少图像处理时间，因为滤波器及其参数在投入临床使用之前必须标准化。商业重建软件的选择可以产生跨部门的可比较结果。制造商通常提供默认过滤器/参数，但这些可能与各种临床情况无关。经过适当的标准化后，可以使用多种合适的过滤器或一种最佳过滤器。
Single photon emission computed tomography (SPECT) imaging is widely implemented in nuclear medicine as its clinical role in the diagnosis and management of several diseases is, many times, very helpful (e.g., myocardium perfusion imaging). The quality of SPECT images are degraded by several factors such as noise because of the limited number of counts, attenuation, or scatter of photons. Image filtering is necessary to compensate these effects and, therefore, to improve image quality. The goal of filtering in tomographic images is to suppress statistical noise and simultaneously to preserve spatial resolution and contrast. The aim of this work is to describe the most widely used filters in SPECT applications and how these affect the image quality. The choice of the filter type, the cut-off frequency and the order is a major problem in clinical routine. In many clinical cases, information for specific parameters is not provided, and findings cannot be extrapolated to other similar SPECT imaging applications. A literature review for the determination of the mostly used filters in cardiac, brain, bone, liver, kidneys, and thyroid applications is also presented. As resulting from the overview, no filter is perfect, and the selection of the proper filters, most of the times, is done empirically. The standardization of image-processing results may limit the filter types for each SPECT examination to certain few filters and some of their parameters. Standardization, also, helps in reducing image processing time, as the filters and their parameters must be standardised before being put to clinical use. Commercial reconstruction software selections lead to comparable results interdepartmentally. The manufacturers normally supply default filters/parameters, but these may not be relevant in various clinical situations. After proper standardisation, it is possible to use many suitable filters or one optimal filter.