GE Research, Niskayuna, NY, United States of America.
Duke University, Durham, NC, United States of America.
Phys Med Biol. 2022 Sep 28;67(19). doi: 10.1088/1361-6560/ac9174.
. X-ray-based imaging modalities including mammography and computed tomography (CT) are widely used in cancer screening, diagnosis, staging, treatment planning, and therapy response monitoring. Over the past few decades, improvements to these modalities have resulted in substantially improved efficacy and efficiency, and substantially reduced radiation dose and cost. However, such improvements have evolved more slowly than would be ideal because lengthy preclinical and clinical evaluation is required. In many cases, new ideas cannot be evaluated due to the high cost of fabricating and testing prototypes. Wider availability of computer simulation tools could accelerate development of new imaging technologies. This paper introduces the development of a new open-access simulation environment for x-ray-based imaging. The main motivation of this work is to publicly distribute a fast but accurate ray-tracing x-ray and CT simulation tool along with realistic phantoms and 3D reconstruction capability, building on decades of developments in industry and academia.. The x-ray-based Cancer Imaging Simulation Toolkit (XCIST) is developed in the context of cancer imaging, but can more broadly be applied. XCIST is physics-based, written in Python and C/C++, and currently consists of three major subsets: digital phantoms, the simulator itself (CatSim), and image reconstruction algorithms; planned future features include a fast dose-estimation tool and rigorous validation. To enable broad usage and to model and evaluate new technologies, XCIST is easily extendable by other researchers. To demonstrate XCIST's ability to produce realistic images and to show the benefits of using XCIST for insight into the impact of separate physics effects on image quality, we present exemplary simulations by varying contributing factors such as noise and sampling.. The capabilities and flexibility of XCIST are demonstrated, showing easy applicability to specific simulation problems. Geometric and x-ray attenuation accuracy are shown, as well as XCIST's ability to model multiple scanner and protocol parameters, and to attribute fundamental image quality characteristics to specific parameters.. This work represents an important first step toward the goal of creating an open-access platform for simulating existing and emerging x-ray-based imaging systems. While numerous simulation tools exist, we believe the combined XCIST toolset provides a unique advantage in terms of modeling capabilities versus ease of use and compute time. We publicly share this toolset to provide an environment for scientists to accelerate and improve the relevance of their research in x-ray and CT.
基于 X 射线的成像方式包括乳房 X 光摄影和计算机断层扫描（CT），广泛用于癌症筛查、诊断、分期、治疗计划和治疗反应监测。在过去的几十年中，这些方式的改进带来了显著提高的疗效和效率，以及显著降低的辐射剂量和成本。然而，这些改进的速度并没有达到理想水平，因为需要进行长时间的临床前和临床评估。在许多情况下，由于制造和测试原型的成本高昂，新的想法无法得到评估。更广泛地使用计算机模拟工具可以加速新成像技术的开发。本文介绍了一种新的基于 X 射线的成像开放访问模拟环境的开发。这项工作的主要动机是公开分发一种快速但准确的射线追踪 X 射线和 CT 模拟工具，以及逼真的体模和 3D 重建能力，这是基于工业和学术界几十年的发展。基于 X 射线的癌症成像模拟工具包（XCIST）是在癌症成像的背景下开发的，但可以更广泛地应用。XCIST 是基于物理的，用 Python 和 C/C++编写，目前由三个主要子集组成：数字体模、模拟器本身（CatSim）和图像重建算法；计划的未来功能包括快速剂量估算工具和严格验证。为了实现广泛的使用，并对新技术进行建模和评估，XCIST 可以由其他研究人员轻松扩展。为了展示 XCIST 生成逼真图像的能力，并展示使用 XCIST 洞察单独物理效应对图像质量的影响的好处，我们通过改变噪声和采样等因素来展示示例模拟。展示了 XCIST 的易于适用性和灵活的功能，适用于特定的模拟问题。展示了几何和 X 射线衰减的准确性，以及 XCIST 对多种扫描仪和协议参数建模的能力，并将基本的图像质量特性归因于特定参数。这项工作是朝着创建用于模拟现有和新兴基于 X 射线成像系统的开放访问平台的目标迈出的重要一步。虽然存在许多模拟工具，但我们相信 XCIST 工具集在建模能力方面具有独特的优势，在易用性和计算时间方面具有优势。我们公开共享这个工具集，为科学家们提供一个环境，以加速和提高他们在 X 射线和 CT 方面的研究的相关性。
