Solid State X-ray Image Intensifier Development

描述（由申请人提供）：长期目标是将新型固态X射线图像增强器（SSXII）开发为首选动态X射线成像设备，其明显优于平板设备（FPD）和X射线图像增强器（XII）。这些优势包括更高的空间分辨率和更小的像素，更低的仪器噪声，从而在更低的曝光下更好地工作，由于可调片内增益而产生的巨大动态范围，无滞后，无重影，以及基于现有固态技术的可扩展生产。SSXII由一系列模块组成，每个模块都有一个光纤锥，可将来自结构化磷光体X射线转换器（如CsI（Tl））的光聚焦到电子倍增电荷耦合器件（EMCCD）上。EMCCD是相对较新的传感器，具有标准CCD的所有优点（高分辨率、高速、低噪声、无滞后），并增加了由额外一行数百个特殊乘法元件产生的片内增益。调节施加到这些电子倍增元件的低电压（几十伏）提供从1到大于1000倍的片上增益。该项目的具体目标包括开发由基于EMCCD的模块阵列组成的原型探测器。由基于EMCCD的商用摄像机组成的2x2系统将能够在有限的视场（FOV）范围内进行早期测试。由于其模块化，由组件构建的更大的3x3阵列将证明设计可扩展到完整的临床FOV，并可完全取代XII或FPD的功能，但具有更高分辨率和更低剂量操作的额外优势。为了评价这些新的阵列探测器，我们将使用线性系统分析获得定量的物理表征，并使用患者特定的快速原型模型，我们将模拟完整的干预措施。操作员友好的基于LabVIEW软件的图形用户界面将在荧光透视和路线图以及血管造影采集期间提供对SSXII的控制。我们还将在动物模型中评估原型SSXII，以在计划进行初步人体研究之前探索各种潜在应用。我们将开始研究的应用是神经和心血管手术，例如用于治疗颅内血管系统深处动脉瘤和狭窄血管的血管内图像引导介入（EIGI）、冠状动脉慢性完全闭塞（CTO）的诊断和治疗以及抗血管生成肿瘤治疗的可能应用的研究。还将探索涉及感兴趣区域（ROI）荧光透视、血管造影和锥形束计算机断层扫描（CBCT）的其他新模式，其中可以使用SSXII的独特高分辨率功能，同时保持患者的较低积分剂量。除EIGI程序外，可能的应用还包括乳房X线摄影CT和断层合成以及其他成像，其中SSXII的低噪声特性将使低剂量视图的数量增加，以减少重建伪影。总之，一旦开发出来，拟议的新SSXII可能会成为未来的动态X射线探测器的选择，具有更高的分辨率和更低的曝光操作，而不是目前的FPD或XII。

DESCRIPTION (provided by applicant): The long-term objective is to develop the new Solid State X-ray Image Intensifier (SSXII) into the preferred dynamic x-ray imaging device with clear advantages over flat-panel devices (FPD) and x-ray image intensifiers (XII). These advantages include higher spatial resolution with smaller pixels, lower instrumentation noise hence better operation at lower exposure, huge dynamic range due to adjustable on-chip gain, no lag, no ghosting, and scalable production based on existing solid state technology. The SSXII consists of an array of modules each with a fiber optic taper that focuses light from a structured phosphor x-ray converter such as CsI(Tl) onto an electron multiplying charge coupled device (EMCCD). EMCCDs are relatively new sensors that have all the benefits of standard CCDs (high resolution, high speed, low noise, no lag) with the addition of on-chip gain created by an extra row of hundreds of special multiplying elements. Adjustment of a low voltage (tens of volts) applied to these electron multiplying elements provides on-chip gains from 1 to greater than 1000X. The specific aims for the project include development of prototype detectors made of arrays of EMCCD-based modules. A 2x2 system made of commercial EMCCD-based cameras will enable early testing over a limited field of view (FOV). The larger 3x3 array built from components because of its modularity will demonstrate a design that is extensible to full clinical FOVs and may completely replace the functions of XIIs or FPDs but with additional benefits of higher resolution and lower dose operation. For the evaluation of these new array detectors, we will obtain quantitative physical characterizations using linear systems analysis and, using patient specific rapid-prototyped phantoms, we will simulate complete interventions. An operator-friendly LabVIEW-software-based graphics user interface will provide control over the SSXII during fluoroscopy with roadmapping and angiography acquisitions. We will also evaluate the prototype SSXIIs in animal models to explore the wide variety of potential applications prior to planning for initial human studies. Applications we will begin to study are to neuro- and cardio-vascular procedures such as endovascular image guided interventions (EIGI) for treating aneurysms and stenotic vessels deep in the cranial vasculature, diagnosis and treatment of coronary chronic total occlusion (CTO) as well as investigations of possible applications to anti-angiogenic tumor treatment. Additional new modalities involving region of interest (ROI) fluoroscopy, angiography, and cone beam computed tomography (CBCT), where the unique high resolution capabilities of the SSXII can be used while maintaining lower integral dose to the patient, will also be explored. Possible applications in addition to EIGI procedures include mammographic CT and tomosynthesis and other imaging where the low noise characteristics of the SSXII will enable increased number of lower dose views to reduce reconstruction artifacts. In summary, the proposed new SSXII once developed may become the future dynamic x-ray detector of choice with higher resolution and lower exposure operation than is possible with current FPDs or XIIs.