Simultaneous Emission and Transmission Mammotomography

描述(由申请人提供)本提案的总体目标是开发一种用于专用乳房和腋窝成像的混合、双模式X射线计算机断层扫描(XCT)和单光子发射计算机断层扫描(SPECT)扫描仪，称为应用特定发射和传输断层扫描(ASETT)。这种非侵入性成像工具旨在提供体积、联合配准的解剖和功能成像数据，以改进乳腺癌的诊断。该系统的XCT组件可以提供乳腺和腋下区域的结构化三维图像，曝光时间接近双视筛查乳房X光摄影，大大提高了乳腺低对比度病变的检测能力，增强了SPECT数据的空间相关衰减校正，并通过客观指导感兴趣区域的选择，便于更好地解释和量化SPECT数据。该提案代表了专用乳房ASETT系统的初步技术开发。之前已经研究过一个原型，专用SPECT扫描仪，并且已经开发出一种龙门架，它有助于一种新型的围绕悬垂乳房的半球轨道获取。这项提议将(1)扩展SPECT相机和机架的功能和性能特点，(2)开发和优化专用XCT扫描仪，以及(3)将两者集成到一个系统中。新的SPECT系统将提高固有空间分辨率(4.5 mm)和固有能量分辨率(10%半高宽)，并扩大视野，完全由计算机控制自由度。XCT系统将结合一种新的X射线源/过滤方法来进行乳房X光摄影成像，使用伪单色光束和最先进的平板、基于闪烁体的数字探测器，以达到&lt；1 mm的各向同性重建分辨率。ASETT探测器系统将针对乳腺和腋窝断层成像进行表征和优化。将开发新的轨道来充分采样乳房和腋下区域，并将研究顺序或同时的XCT/SPECT成像、分辨率、信噪比和对乳房体积的辐射剂量之间的权衡。将使用适当的模体来定量评估图像质量和剂量。最后，双模式ASETT系统将通过先导性患者研究进行临床评估。

DESCRIPTION (provided by applicant)The overall goal of this proposal is to develop a hybrid, dual-modality x-ray computed tomography (XCT) and single photon emission computed tomography (SPECT) scanner for dedicated breast and axillary imaging, termed application specific emission and transmission tomography (ASETT). This noninvasive imaging tool is intended to provide volumetric, co-registered anatomical and functional imaging data for improved diagnosis of breast cancer. The XCT component of the system can provide structural three-dimensional images of the breast and axillary region with exposure near that of dual-view screening mammography, greatly improving the detectability of low contrast lesions in the breast, enhancing the spatially-dependent attenuation correction of the SPECT data, and facilitating better interpretation and quantification of the SPECT data by objectively guiding region of interest selection. This proposal represents the initial technology development for a dedicated breast ASETT system. A prototype, dedicated SPECT scanner has previously been investigated, and a gantry has been developed that facilitates a new class of hemispherical acquisition orbits about a pendant breast. This proposal will (1) extend the capabilities and performance characteristics of the SPECT camera and gantry, (2) develop and optimize the dedicated XCT scanner, and (3) integrate the two into a single system. The new SPECT system will have improved intrinsic spatial resolution (4.5mm) and intrinsic energy resolution (10% FWHM), and an expanded field-of-view, with fully computer controllable degrees of freedom. The XCT system will incorporate a novel x-ray source/filtration approach to mammographic imaging with a pseudo- monochromatic beam and a state-of-the-art, flat-panel, scintillator-based digital detector to reach <1mm isotropic reconstructed resolution. The ASETT detector system will be characterized and optimized for tomographic breast and axillary imaging. Novel orbits to sufficiently sample the pendant breast and axillary region will be developed, and trade-offs between sequential or simultaneous XCT/SPECT imaging, resolution, signal-to-noise, and radiation dose to the breast volume will be investigated. Appropriate phantoms will be used to quantitatively assess image quality and dose. Finally, the dual-modality ASETT system will be clinically evaluated with pilot patient studies.