A Dual Resolution Cone Beam CT System for 3-D Breast Imaging

描述（由申请人提供）：尽管发展了新的成像方式，x射线乳房x线摄影仍然是筛查、诊断和治疗乳腺癌的主要工具。然而，有限的敏感性和乳房实质上的钙化和肿块的叠加损害了其在这些手术中的价值。基于平板（FP）的锥形束CT （CBCT）技术的最新发展开创了一种新的方法，称为专用或挂式几何锥形束乳腺CT技术，该技术将高对比度灵敏度与乳腺解剖和病变的真实三维再现相结合。然而，尽管基于FP的CBCT提供的空间分辨率可能高于传统CT技术提供的空间分辨率，但在检测和可视化小钙化时，它仍然明显低于乳房x线摄影成像技术。在本项目中，我们建议开发、研究和评估一种被称为双分辨率CBCT （DRCBCT）的新技术，以使3D乳房图像的空间分辨率比FPCBCT更高。利用该技术，利用FP检测器获取全场CBCT图像，用于选择感兴趣体积（VOI）。然后重新定位乳房，使VOI居中于等距中心。通过增加准直器将x射线场限制在VOI上，并使用小视场CCD探测器在适当的曝光水平下获取VOI的高分辨率投影图像。然后通过重新扫描或计算先前获得的FPCBCT图像的重新投影来填充高分辨率VOI CBCT所需的截断区域，从而获得有限高度，全宽度的FP图像。由于高分辨率图像的采集和重建仅限于VOI，因此可以将患者剂量和计算时间保持在合理的水平，使其在临床应用中更加实用。在R21阶段（第一年），我们建议通过计算机模拟和台式成像实验来研究和证明双分辨率CBCT技术的可行性。在R33阶段（第2,3,4年），我们建议构建，优化和研究双分辨率CBCT的原型系统。将获得幻影和患者图像，以展示双分辨率CBCT技术的性能改进以及在乳腺癌诊断和治疗中的潜在应用。双分辨率CBCT技术的成功开发和研究将为乳腺三维成像提供有力的工具。增加的高分辨率能力，加上提高的对比灵敏度和乳腺CT图像的真正3d性质，可能使双分辨率CBCT技术取代甚至超越传统的乳房x光检查，以改善乳腺癌的诊断和管理，包括图像引导活检，手术计划和针头定位。题目A用于乳腺三维成像的双分辨率锥束CT系统项目叙述尽管有新的成像方式的发展，x射线乳房x线摄影仍然是乳腺癌筛查、诊断和治疗的主要工具。然而，有限的敏感性和乳房实质上的钙化和肿块的叠加损害了其在这些手术中的价值。基于平板（FP）的锥形束CT （CBCT）技术的最新发展开创了一种新的方法，称为专用或挂式几何锥形束乳腺CT技术，该技术将高对比度灵敏度与乳腺解剖和病变的真实三维再现相结合。然而，尽管基于FP的CBCT提供的空间分辨率可能高于传统CT技术提供的空间分辨率，但在检测和可视化小钙化时，它仍然明显低于乳房x线摄影成像技术。在本项目中，我们建议开发、研究和评估一种被称为双分辨率CBCT （DRCBCT）的新技术，以使3D乳房图像的空间分辨率比FPCBCT更高。利用该技术，利用FP检测器获取全场CBCT图像，用于选择感兴趣体积（VOI）。然后重新定位乳房，使VOI居中于等距中心。通过增加准直器将x射线场限制在VOI上，并使用小视场CCD探测器在适当的曝光水平下获取VOI的高分辨率投影图像。然后通过重新扫描或计算先前获得的FPCBCT图像的重新投影来填充高分辨率VOI CBCT所需的截断区域，从而获得有限高度，全宽度的FP图像。由于高分辨率图像的采集和重建仅限于VOI，因此可以将患者剂量和计算时间保持在合理的水平，使其在临床应用中更加实用。在R21阶段（第一年），我们建议通过计算机模拟和台式成像实验来研究和证明双分辨率CBCT技术的可行性。在R33阶段（第2,3,4年），我们建议构建，优化和研究双分辨率CBCT的原型系统。将获得幻影和患者图像，以展示双分辨率CBCT技术的性能改进以及在乳腺癌诊断和治疗中的潜在应用。双分辨率CBCT技术的成功开发和研究将为乳腺三维成像提供有力的工具。增加的高分辨率能力，加上提高的对比灵敏度和乳腺CT图像的真正3d性质，可能使双分辨率CBCT技术取代甚至超越传统的乳房x光检查，以改善乳腺癌的诊断和管理，包括图像引导活检，手术计划和针头定位。

DESCRIPTION (provided by applicant: Despite the development of new imaging modalities, x-ray mammography remains the main tool for screening, diagnosis and management of breast cancers. However, the limited sensitivity and superimposition of calcifications and masses on the breast parenchyma have compromised its value in these procedures. Recent development of flat panel (FP) based cone beam CT (CBCT) techniques have initiated a new approach referred to as the dedicated or pendant geometry cone beam breast CT technique which couples high contrast sensitivity with true 3-D rendition of breast anatomy and lesions. However, although the spatial resolution offered by FP based CBCT is potentially higher than those provided by the conventional CT techniques, it is still significantly lower than those of mammographic imaging techniques as required for detecting and visualizing small calcifications. In this project, we propose to develop, investigate and evaluate a new technique referred to as the dual-resolution CBCT (DRCBCT) technique to allow the spatial resolution of the 3D breast images to be improved beyond those achievable with FPCBCT. With this technique, a FP detector is used to acquire full field CBCT images which are used to select a volume-of-interest (VOI). The breast is then re-positioned to have the VOI centered to the iso-center. A collimator is added to limit the x-ray field to the VOI and a small field of view CCD detector is used to acquire high resolution projection images for the VOI at an appropriate exposure level. Limited height, full width FP images are then obtained by re- scanning or by computing the re-projections from previously obtained FPCBCT images to fill in the truncated area as required for high resolution VOI CBCT. Because high resolution image acquisition and reconstruction are limited to the VOI, both patient dose and computation time can be kept at a reasonable level, making it more practical to implement and use for clinical applications. In the R21 phase (Year 1), we propose to investigate and demonstrate the feasibility of the dual resolution CBCT technique with computer simulation and bench top imaging experiments. In the R33 phase (Years 2, 3 and 4), we propose to construct, optimize and investigate a prototype system for dual resolution CBCT. Both phantom and patient images will be obtained to demonstrate the performance improvement by the dual resolution CBCT techniques and potential applications in the diagnosis and management of breast cancers. Successful development and investigation of the dual resolution CBCT technique may provide a powerful tool for 3-D breast imaging. The addition of high resolution capability, coupled with improved contrast sensitivity and the true 3-D nature of breast CT images may allow the dual resolution CBCT technique to replace and even surpass conventional mammography for improved diagnosis and management of breast cancers, including image guided biopsy, surgical planning, and needle localization. Proposal to be submitted to the NIH-NCI as R21/R33 project Title A Dual Resolution Cone Beam CT System for 3-D Breast Imaging Project Narrative Despite the development of new imaging modalities, x-ray mammography remains the main tool for screening, diagnosis and management of breast cancers. However, the limited sensitivity and superimposition of calcifications and masses on the breast parenchyma have compromised its value in these procedures. Recent development of flat panel (FP) based cone beam CT (CBCT) techniques have intitiated a new approach referred to as the dedicated or pendant geometry cone beam breast CT technique which couples high contrast senstivity with true 3-D rendition of breast anatomy and lesions. However, although the spatial resolution offered by FP based CBCT is potentially higher than those provided by the conventional CT techniques, it is still significantly lower than those of mammographic imaging techniques as required for detecting and visualizing small calcifications. In this project, we propose to develop, investigate and evaluate a new technique referred to as the dual-resolution CBCT (DRCBCT) technique to allow the spatial resolution of the 3D breast images to be improved beyond those achievable with FPCBCT. With this technique, a FP detector is used to acquire full field CBCT images which are used to select a volume-of-interest (VOI). The breast is then re-positioned to have the VOI centered to the iso-center. A collimator is added to limit the x-ray field to the VOI and a small field of view CCD detector is used to acquire high resolution projection images for the VOI at an appropriate exposure level. Limited height, full width FP images are then obtained by re- scanning or by computing the re-projections from previously obtained FPCBCT images to fill in the truncated area as required for high resolution VOI CBCT. Because high resolution image acquisition and reconstruction are limited to the VOI, both patient dose and computation time can be kept at a reasonable level, making it more practical to implement and use for clinical applications. In the R21 phase (Year 1), we propose to investigate and demonstrate the feasibility of the dual resolution CBCT technique with computer simulation and bench top imaging experiments. In the R33 phase (Years 2, 3 and 4), we propose to construct, optimize and investigate a prototype system for dual resolution CBCT. Both phantom and patient images will be obtained to demonstrate the performance improvement by the dual resolution CBCT techniques and potential applications in the diagnosis and management of breast cancers. Successful development and investigation of the dual resolution CBCT technique may provide a powerful tool for 3-D breast imaging. The addition of high resolution capability, coupled with improved contrast sensitivity and the true 3-D nature of breast CT images may allow the dual resolution CBCT technique to replace and even surpass conventional mammography for improved diagnosis and management of breast cancers, including image guided biopsy, surgical planning, and needle localization.