Probing Dose Limits in Cardiac SPECT with Reconstruction and Personalized Imaging

通过重建和个性化成像探测心脏 SPECT 的剂量限制

• 批准号: 9061011
• 负责人: Michael A King
• 金额: $ 77.05万
• 依托单位: ILLINOIS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-05-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9061011
• 关键词: 4D Imaging; Acceleration; Accounting; Address; Adopted; Algorithms; American; Appearance; Attention; Blood flow; Breathing; Cardiac; Cardiac Catheterization Procedures; Cardiology; Cessation of life; Characteristics; Clinic; Clinical; Clinical Protocols; Clinical Research; Communities; Computational algorithm; Computer software; Data; Development; Diagnostic; Discipline of Nuclear Medicine; Dose; Dose-Limiting; Electromagnetic Energy; Evaluation; Financial compensation; Four-dimensional; Goals; Government; Health; Heart; Heart Diseases; Image; Lead; Machine Learning; Malignant Neoplasms; Measurement; Medical Imaging; Methods; Modeling; Modification; Motion; Myocardial perfusion; Noise; Nuclear; Obesity; Patients; Performance; Perfusion; Persons; Pharmacologic Substance; Physicians; Population; Procedures; Process; Professional Organizations; Protocols documentation; Radiation; Radiation Protection; Radioactive; Reader; Recommendation; Research Project Grants; Societies; Stress; Sum; System; Techniques; Tissues; Tracer; Training; Translating; Translational Research; Ultrasonography; Work; X-Ray Computed Tomography; base; cardiac single photon emission computed tomography; clinical practice; computer program; cost; diagnostic accuracy; experience; heart motion; image processing; image reconstruction; imaging agent; imaging modality; improved; individual patient; interest; predictive modeling; reconstruction; respiratory; sensor; single photon emission computed tomography; user-friendly

DESCRIPTION (provided by applicant): Radiation exposure of patients during medical imaging has become a major concern, with computed tomography (CT) and cardiac single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) being the biggest contributors. In this project our aim will be to dramatically reduce radiation dose in cardiac SPECT MPI based on inexpensive software techniques that can be translated readily to clinical practice. Our initial results suggest that at least an eightfold reduction in radiation doe might be possible, which could lead to an estimated reduction of 6500 cancer deaths per year in the U.S. alone. In lay terms, cardiac SPECT MPI is used routinely to evaluate heart disease, allowing the physician to assess blood flow reaching the heart wall, the motion of the heart, and whether the heart wall's tissue is viable. This form of imaging involves administration of a radioactive pharmaceutical (tracer) to the patient, which exposes the patient to radiation; thus, i would be desirable to minimize tracer dose used during imaging. Image quality is determined by the amount of tracer used, and these levels were chosen prior to recent technological improvements that can produce high-quality images at lower dose; therefore, there is clear evidence that doses can be lowered, and indeed there is considerable current interest in doing so. We are proposing a translational research project to thoroughly and quantitatively study the extent to which administered dose might be reduced without sacrificing image quality. This work will build, in particular, on new four-dimensional (4D) image reconstruction techniques and respiratory motion compensation approaches we have developed. Furthermore, we propose a new dosing approach we call "personalized imaging", in which a computer algorithm will be trained to predict, for a given patient, the minimum dose required to obtain the current level of image quality, so that the administered dose is no more than necessary. In 4D reconstruction, a computer algorithm tracks the heart's beating motion, and uses this information to improve image quality by smoothing image noise in a way that preserves image details. In respiratory motion compensation, the patient's breathing and body motions are tracked by external sensors, and this information is used to reduce the appearance of motion blur in the images, and thereby improve diagnostic accuracy. The proposed "personalized imaging" approach builds on our group's extensive experience in machine learning. We expect that the combination of these various strategies will greatly reduce radiation dose, and because the improvements are based on software, the cost of these enhancements is very low. The project will result in recommendations for image reconstruction algorithms and parameters to be used in the clinic, along with corresponding tracer dose recommendations. The "personalized imaging" method will be implemented as a user-friendly computer program that customizes the dose for each given patient.

描述（由申请人提供）：医学成像期间患者的辐射暴露已成为一个主要问题，计算机断层扫描（CT）和心脏单光子发射计算机断层扫描（SPECT）心肌灌注成像（MPI）是最大的贡献者。在这个项目中，我们的目标将是显着减少辐射剂量的心脏SPECT MPI的基础上廉价的软件技术，可以很容易地转化为临床实践。我们的初步结果表明，辐射剂量至少可以减少八倍，这可能导致仅在美国每年就减少6500例癌症死亡。 通俗地说，心脏SPECT MPI通常用于评估心脏疾病，允许医生评估到达心脏壁的血流，心脏的运动以及心脏壁的组织是否有活力。这种形式的成像涉及向患者施用放射性药物（示踪剂），这使患者暴露于辐射;因此，期望最小化成像期间使用的示踪剂剂量。图像质量取决于所用示踪剂的量，这些水平是在最近的技术改进之前选择的，可以在较低剂量下产生高质量的图像;因此，有明确的证据表明可以降低剂量，而且目前确实有相当大的兴趣这样做。 我们正在提出一个转化研究项目，以彻底、定量地研究在不牺牲图像质量的情况下可以减少给药剂量的程度。这项工作将建立，特别是新的四维（4D）图像重建技术和呼吸运动补偿方法，我们已经开发。此外，我们提出了一种新的给药方法，我们称之为“个性化成像”，其中计算机算法将被训练来预测，对于给定的患者，获得当前图像质量水平所需的最小剂量，使得所施用的剂量不超过必要的剂量。 在4D重建中，计算机算法跟踪心脏的跳动运动，并使用此信息通过以保留图像细节的方式平滑图像噪声来改善图像质量。在呼吸运动补偿中，患者的呼吸和身体运动由外部传感器跟踪，并且该信息用于减少图像中的运动模糊的出现，从而提高诊断准确性。提出的“个性化成像”方法建立在我们团队在机器学习方面的丰富经验之上。 我们预计，这些不同的策略相结合，将大大减少辐射剂量，因为改进是基于软件，这些增强的成本是非常低的。该项目将产生临床使用的图像重建算法和参数的建议，沿着相应的示踪剂剂量建议。“个性化成像”方法将作为一个用户友好的计算机程序来实现，该程序可以为每个给定的患者定制剂量。