In computed tomography (CT)-imaging an optimal compromise between the radiation burden and the image quality for the imaging task is needed. Lower-dose CT is desirable, however, lowering the dose results in a lower signal-to-noise ratio and therefore in a reduced image quality. In this research, we aim to develop a tool to simulate lower-dose scans from an existing standard-dose scan. The main application of this tool is to determine the lowest possible radiation dose that still produces sufficient clinical information. The x-ray tube current reduction is modeled by estimating the noise equivalent number of photons in the high exposure scan and applying a thinning technique to reduce that number. The proposed method accounts for the bowtie filter, for the electronic system noise, for the noise correlation between neighboring detector elements, for the beam hardening effect, and for the non-linear smoothing filter in very low-dose scans. Several phantom studies with different acq...

中文翻译：

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来自可用高剂量扫描的低剂量X射线CT模拟

在计算机断层扫描（CT）成像中，需要在辐射负担和成像任务的图像质量之间达到最佳折衷。较低剂量的CT是理想的，但是，降低剂量会导致较低的信噪比，因此会降低图像质量。在这项研究中，我们旨在开发一种工具来模拟现有标准剂量扫描的小剂量扫描。该工具的主要应用是确定仍可产生足够临床信息的最低可能放射剂量。通过估算高曝光扫描中光子的噪声等效数量并应用稀化技术来减少该数量，可以对X射线管电流的减少进行建模。所提出的方法考虑了领结滤波器，电子系统噪声，相邻检测器元件之间的噪声相关性，用于光束硬化效果，以及用于极低剂量扫描中的非线性平滑滤波器。具有不同获取方式的几个幻像研究...