Development of a High Sensitivity, X-ray Detector Technology Based on Polycrystalline Mercuric Iodide for Volumetric Breast Imaging

开发基于多晶碘化汞的高灵敏度 X 射线探测器技术，用于体积乳腺成像

• 批准号: 9236895
• 负责人: LARRY E ANTONUK
• 金额: $ 64.99万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2020-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9236895
• 关键词: Accounting; Address; Affect; Breast; Breast Cancer Detection; Cesium; Charge; Collaborations; Data; Deposition; Development; Devices; Diagnosis; Digital Breast Tomosynthesis; Dose; Early identification; Effectiveness; Evaluation; Exhibits; Exposure to; Fluoroscopy; Goals; Image; Indium; Individual; Investigation; Iodides; Mammary Gland Parenchyma; Mammography; Mass in breast; Methods; Modern Medicine; Modification; Noise; Performance; Printing; Property; Radiation; Radiation therapy; Research; Research Methodology; Resolution; Risk; Roentgen Rays; Selenium; Sensitivity and Specificity; Signal Transduction; Structure; System; Techniques; Technology; Time; Tissues; Variant; Work; abstracting; base; breast imaging; cone-beam computed tomography; contrast imaging; detector; falls; imaging system; improved; innovation; interest; iterative design; malignant breast neoplasm; novel; operation; prototype; quantum; response; screening; statistics; tool

Project Summary/Abstract The task of correctly identifying suspicious masses in the breast is often complicated by the confusing overlap of anatomical features present in the projection images provided by mammography. For that reason, there has been growing interest in obtaining volumetric information through a technique called digital breast tomosynthesis (DBT). DBT has shown promise for improving sensitivity and specificity in breast imaging compared to mammography by providing depth information that helps to distinguish overlapping breast tissue. This technique is most commonly performed using the technology of active matrix, flat-panel imagers (AMFPIs) which incorporate an x-ray converter (in the form of a layer of cesium iodide (CsI:Tl) or amorphous selenium (a-Se) deposited on a pixelated array) to detect the incident radiation. A single DBT view typically involves acquisition of 9 to 25 projection images and it is clinically desirable that the cumulative dose per view be no more than that of a single-view mammogram. However, the relatively modest amount of signal generated by each X ray in CsI:Tl and a-Se leads to technical limitations that constrain the conditions under which the projection images are acquired – which can significantly affect image quality as well as impede efforts to minimize dose. To overcome this problem, the proposed research seeks to develop an alternative form of x- ray converter based on polycrystalline mercuric iodide and fabricated using a screen-print method – referred to as SP HgI2. SP HgI2 has been shown to be capable of providing at least three times more signal per X ray than a-Se or CsI:Tl and, as a result, would help to address technical limitations in AMFPIs used for DBT. However, further development of this novel converter is required to improve other important converter and imager-related properties (including the reduction of charge trapping effects and non-uniformity in pixel-to-pixel signal response). The specific aims of the project therefore focus on achieving a high level of performance for each of these properties. These aims will be accomplished through systematic investigation of a number of strategies chosen to improve different aspects of converter and imager performance. The strategies consist of modifications to the methods used to fabricate the SP HgI2 converters combined with the introduction of a grid structure into those converters. The methodology of the research will be based on iterative design, fabrication and evaluation of prototype converters employing these strategies – with the information obtained from a given set of prototypes used to improve subsequent prototypes. The converters will be deposited on simple detector substrates (which facilitate relatively rapid evaluation of a limited number of properties) as well as on AMFPI arrays (which allow complete performance characterization). The expected impact of the new converter technology made possible by the research will be a significant improvement in the effectiveness of digital breast tomosynthesis, including possible dose reduction – along with the potential for facilitating dose reduction in other applications such as breast CT, fluoroscopy and cone-beam CT in radiation therapy.

项目总结/摘要 正确识别乳腺可疑肿块的任务往往是复杂的混淆重叠 存在于由乳房X线照相术提供的投影图像中的解剖特征的特征。因此， 通过一种称为数字乳腺的技术获得体积信息的兴趣越来越大 断层合成（DBT）。DBT有望提高乳腺成像的灵敏度和特异性 与乳房X线摄影相比，它提供了有助于区分重叠乳房组织的深度信息。 该技术最常使用有源矩阵平板成像器（AMFPI）技术来执行 其包括X射线转换器（以碘化铯（CsI：Tl）或无定形硒层的形式 （a-Se）沉积在像素化阵列上）以检测入射辐射。单个DBT视图通常涉及 采集9到25个投影图像，并且临床上期望每次视图的累积剂量不超过 比单视图乳房X光片的效果更好。然而，由所产生的相对适度的信号量 CsI：Tl和a-Se中的每种X射线都导致技术限制，这些限制限制了 这会显著影响图像质量以及妨碍 尽量减少剂量。为了克服这个问题，拟议的研究试图开发一种替代形式的x- 基于多晶碘化汞并使用丝网印刷方法制造的射线转换器-参见 作为SP HgI 2。SPHgI 2已被证明能够提供至少三倍于X射线的信号 比a-Se或CsI：Tl更好，并且因此将有助于解决用于DBT的AMFPI中的技术限制。 然而，需要进一步开发这种新型转换器以改进其他重要的转换器， 与成像器相关的特性（包括电荷捕获效应的减少和像素间的不均匀性 信号响应）。因此，该项目的具体目标侧重于实现高水平的业绩， 每一个这些属性。这些目标将通过系统地调查一些 所选择的策略可改善转换器和成像器性能的不同方面。这些战略包括 对用于制造SP HgI 2转换器的方法进行修改， 在这些转换器中。研究方法将基于迭代设计、制造 和评估原型转换器采用这些策略-与信息获得的给定的 用于改进后续原型的一组原型。转换器将沉积在简单的探测器上 基质（其有利于相对快速地评估有限数量的性质）以及AMFPI上 阵列（允许完整的性能表征）。新转换器的预期影响 这项研究所带来的技术将大大提高数字技术的有效性。 乳腺断层合成，包括可能的剂量降低-沿着促进剂量降低的可能性 在其他应用中，例如乳腺CT、荧光透视和放射治疗中的锥形束CT。