TOMOSYNTHESIS FOR IMPROVED PULMONARY NODULE DETECTION

描述（改编自申请人摘要）：这些研究的目的 目的是开发和评估一种方法， 肺结节，使用数字断层合成技术。数字 通过提供三维信息来增强传统的胸部检查 通过一系列纵向切片图像。这些切片图像是 从在不同的时间点采集的一组离散投影图像重建 角度，使用传统的X射线管和新的数字平板X射线 检测器断层合成的图像可以被逐切片地观察或作为3D图像被观察。 在"虚拟荧光透视"观察环境中的体绘制投影。的 断层合成的诊断益处是使用3D信息来改善 通过消除混淆来检测和区分肺结节 覆盖结构。CT仍将是临床检查的金标准 一旦检测到结节，断层合成提供低剂量/低成本 提高初始检测精度的方法。在临床上， 无论何时安排数字PA/侧胸检查都将采集图像， 但是以常规曝光水平的一半获取横向图像。 结果，使用新的平板探测器，将是一个PA膜， 改善的图像质量，具有传统图像质量的侧面，以及 三维断层合成数据集，全部在整体曝光下采集 与标准屏-片PA/侧位胸部检查相当。三种不同的 本提案将研究断层合成算法：传统的 平移相加断层合成，一种调谐孔径计算机断层成像（TACT） 算法与改进的图像配准，和一个矩阵求逆 用于改进的残余模糊消除的层析合成（MITS）算法 不在目标平面内的结构。项目的具体目标 包括：构建数字断层合成胸部系统;改进 MITS算法;三维观察环境的开发; 图像采集几何结构的优化;断层合成的评价 伪影;患者剂量优化; MITS、TACT和 "常规"断层合成;以及对以下假设的临床测试， X射线断层合成技术提高了肺结节的检测， 用传统的放射线照相术。

DESCRIPTION (Adapted from Applicant's Abstract): The purpose of these studies is to develop and evaluate a method for improving clinical detection of pulmonary nodules, using a technique known as digital tomosynthesis. Digital augments a conventional chest exam by providing three-dimensional information through a series of longitudinal slice images. These slice images are reconstructed from a set of discrete projection images acquired at different angles, using a conventional x-ray tube and a new digital flat-panel x-ray detector. The tomosynthesized images may be viewed slice-by-slice or as a 3-D volume-rendered projection in a "virtual fluoroscopy" viewing environment. The diagnostic benefit of tomosynthesis is the use of 3-D information to improve detection and discrimination of pulmonary nodules by eliminating the confusion of overlying structures. CT would remain the gold-standard for clinical workup once nodules are detected, with tomosynthesis providing a low-dose/low-cost method for improving initial detection accuracy. Clinically the tomosynthesis images would be acquired whenever a digital PA/lateral chest exam is scheduled, but with the lateral image acquired at half the conventional exposure level. The results, using the new flat-panel detector, would be a PA film with improved image quality, a lateral with conventional image quality, and a three-dimensional tomosynthesis data set, all acquired at an overall exposure comparable to a standard screen-film PA/lateral chest exam. Three different tomosynthesis algorithms will be investigated in this proposal: traditional shift-and-add tomosynthesis, a Tuned Aperture Computed Tomography (TACT) algorithm with improved registration of images, and a Matrix Inversion Tomosynthesis (MITS) algorithm for improved elimination of residual blurring from structures not in the plane of interest. The specific aims of the project include: construction of a digital tomosynthesis chest system; improvement of the MITS algorithm; development of a three-dimensional viewing environment; optimization of image acquisition geometry; evaluation of tomosynthesis artifacts; optimization of patient dose; comparison of MITS, TACT, and "conventional" tomosynthesis; and a clinical test of the hypothesis that tomosynthesis improves the detection of pulmonary nodules over what is possible with conventional radiography.