DUAL-ENERGY SCREENING FOR NODULAR DISEASE

这些研究的目的是开发和评估一个实用的 利用双能量胸部摄影筛查结节性疾病的方法。 双能量技术用于去除骨或软组织 通过利用不同的能量， 骨和软组织中X射线衰减的依赖性。 该技术 使用在不同时间获得的两个射线照相图像的线性组合， X射线能量，选择加权系数以消除骨骼 或软组织。 提高软组织结节的可见性的能力 并测定结节钙含量是诊断的优势 双能源。 将涉及四个主要研究领域。 首先，一种新的混合动力车 将对双能量卡匣进行评价， 采集常规胶片图像和数字双能图像。 其次，双能量图像的信噪比（SNR）将是 通过使用X射线均衡和各种成像算法来改进。 第三，将在X射线均衡器中添加扫描栅格组件， 提供改进的散射抑制并因此提供改进的SNR。 第四， 将对自动结节检测算法进行评价， 双能量组织成像 在每一个研究领域， 重点将放在详细评价技术改进， 实施和临床相关诊断改进的实用性 本建议中的具体研究包括： 混合胶片/数字双能量暗盒的评价，SNR改善 在具有X射线均衡的双能量成像中， 用于低成本均衡的通用滤波器，扫描网格的构造 对于X射线均衡器，多板集成可提高SNR， 剂量效率，成像板的匹配滤波， SNR，组织和低能量图像的组合以改善SNR， 相关降噪技术的优化，对比细节 研究骨和软组织图像，临床结节检测 骨显像中钙测定的研究、评价及临床应用 自动结节检测算法（包括人工 神经网络）。

The purpose of these studies is to develop and evaluate a practical screening method for nodular disease using dual-energy chest radiography. The dual-energy technique is used to subtract either bone or soft-tissue structures from a radiographic image, by utilizing the different energy dependence of x-ray attentuation in bone and soft-tissue. The technique uses a linear combination of two radiographic images acquired at different x-ray energies, with the weighting coefficient chosen to cancel either bone or soft-tissue. The ability to improve conspicuity of soft-tissue nodules and to determine calcium content of nodules are the diagnostic advantages of dual-energy. Four primary areas of research will be addressed. First, a new hybrid dual-energy cassette will be evaluated which permits simultaneous acquisition of a conventional film image and digital dual-energy images. Second, the signal-to-noise ratio (SNR) of dual-energy images will be improved by using x-ray equalization and a variety of imaging algorithms. Third, a scanning grid assembly will be added to the x-ray equalizer to provide improved scatter rejection and therefore improved SNR. Fourth, an evaluation of automated nodule detection algorithms will be performed on the dual-energy tissue images. In each of these areas of research, emphasis will be placed on detailed evaluation of technical improvement, practicality of implementation and clinically-related diagnostic improvemen The specific studies in this proposal include: implementation and evaluation of a hybrid film/digital dual-energy cassette, SNR improvement in dual-energy imaging with x-ray equalization, evaluation of inexpensive generic filters for low-cost equalization, construction of a scanning grid for the x-ray equalizer, multiple-plate integration for improved SNR and dose efficiency, matched filtering of imaging plates for further improved SNR, combination of the tissue and low-energy images for improved SNR, optimization of the correlated noise reduction technique, a contrast-detail study of the bone and soft-tissue images, a clinical nodule detection study, evaluation of the calcium determination in the bone image, and an evaluation of automated nodule detection algorithms (including artificial neural networks).