MR-assisted PET data optimization for neuroimaging studies

用于神经影像研究的 MR 辅助 PET 数据优化

• 批准号: 8439120
• 负责人: Ciprian Catana
• 金额: $ 68.04万
• 依托单位: MASSACHUSETTS GENERAL HOSPITAL
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8439120
• 关键词: Accounting; Affect; Alzheimer' s Disease; Biological Markers; Biological Process; Bone Tissue; Brain; Brain Pathology; Clinical; Clinical Trials; Collection; Complex; Data; Data Quality; Databases; Development; Disease; Disease Progression; Gamma Rays; Glucose; Goals; Head; Head Movements; Hippocampus (Brain); Image; Joints; Kinetics; Label; Lead; Longitudinal Studies; Magnetic Resonance Imaging; Maps; Measurement; Measures; Metabolic; Methods; Modeling; Morphologic artifacts; Motion; Neurologic; Outcome; Patients; Performance; Perfusion; Photons; Physiological; Positron-Emission Tomography; Predictive Value; Protocols documentation; Reproducibility; Research; Resolution; Sample Size; Scanning; Structure; Techniques; Testing; Therapeutic Agents; Time; Tissues; Tracer; Training; Translating; Water; Work; attenuation; base; bone imaging; data acquisition; detector; healthy volunteer; human subject; imaging modality; improved; in vivo; minimally invasive; nervous system disorder; neuroimaging; new technology; novel; novel therapeutics; patient population; public health relevance; radiotracer; transmission process; uptake

DESCRIPTION (provided by applicant): Positron emission tomography (PET) and magnetic resonance imaging (MRI) are two of the most powerful imaging modalities currently in use for neurological studies. Recently, scanners capable of simultaneous PET and MR data acquisition in human subjects have become a reality and this new technology opens up possibilities impossible to realize using sequentially acquired data. One such example is using the MR data for improving the performance of the PET scanner. While PET as a technique has many advantages, including the fact that it could potentially provide a quantitative means to assess in vivo biological processes, the accuracy of the PET measurements is confounded by several factors. For example, attenuation and scatter correction have to be performed to account for the interactions of the gamma-ray photons in the subject before reaching the detectors; motion correction has to be applied to avoid the degradation of the images due to involuntary head movements; partial volume effect correction is required due to the relatively limited spatial resolution; the radiotracer arterial input function is required for kinetic modeling. The spatially and temporally correlated MR data acquired simultaneously offer the unique opportunity to correct for these confounding effects and improve the reliability and reproducibility of the PET estimates. Although many neurological applications could benefit from these methodological improvements, in this proposal we are focusing on Alzheimer's disease (AD) for demonstrating the potential of improved MR-PET quantification. MRI and PET are widely used and provide largely complementary information in assessment of AD patients. Equally important, AD is a great test situation for the development of MR-PET because the confounding factors mentioned above are especially important in this patient population and are a substantial limitation of existing PET research. Specifically, we will: (1) Develop and validate an accurate MR-based head attenuation correction method. We hypothesize that using novel sequences for imaging the bone tissue and improved methods for combining these with high resolution anatomical MR, head attenuation maps more accurate than those obtained from segmented CT can be obtained; (2) Improve the quantification of PET data using the simultaneously acquired MR data. We hypothesize that the temporally and spatially correlated MR data will allow us to improve the reliability of the PET data by performing motion and partial volume effect corrections and estimating the radiotracer arterial input function; (3) Evaluate the added value of MR-optimized PET measurements as biomarkers of disease progression in AD. We hypothesize that the effect size of PET differences would be increased and the variability in PET measurements would be decreased after MR-optimization.

描述（由申请人提供）：正电子发射断层扫描（PET）和磁共振成像（MRI）是目前用于神经学研究的两种最强大的成像方式。最近，能够同时采集人体 PET 和 MR 数据的扫描仪已成为现实，这项新技术开辟了使用顺序采集数据不可能实现的可能性。其中一个例子是使用 MR 数据来提高 PET 扫描仪的性能。虽然 PET 作为一种技术具有许多优点，包括它有可能提供评估体内生物过程的定量方法，但 PET 测量的准确性受到几个因素的影响。例如，必须执行衰减和散射校正，以解释伽马射线光子在到达探测器之前在对象中的相互作用；必须应用运动校正以避免由于头部不自觉运动而导致图像质量下降；由于空间分辨率相对有限，需要进行部分体积效应校正；动力学建模需要放射性示踪剂动脉输入函数。空间上的 同时采集的时间相关 MR 数据提供了纠正这些混杂效应并提高 PET 估计的可靠性和可重复性的独特机会。尽管许多神经学应用可以从这些方法改进中受益，但在本提案中，我们将重点放在阿尔茨海默氏病 (AD) 上，以证明改进 MR-PET 定量的潜力。 MRI 和 PET 被广泛使用，并在 AD 患者的评估中提供了很大程度上补充的信息。同样重要的是，AD 是 MR-PET 发展的一个很好的测试情况，因为上述混杂因素在该患者群体中尤其重要，并且是现有 PET 研究的重大限制。具体来说，我们将：（1）开发并验证一种精确的基于MR的磁头衰减校正方法。我们假设，使用新的骨组织成像序列以及将这些序列与高分辨率解剖 MR 相结合的改进方法，可以获得比分段 CT 获得的头部衰减图更准确的头部衰减图； (2) 使用同时采集的 MR 数据改进 PET 数据的量化。我们假设时间和空间相关的 MR 数据将使我们能够通过执行运动和部分体积效应校正以及估计放射性示踪剂动脉输入函数来提高 PET 数据的可靠性； (3) 评估附加值 MR 优化的 PET 测量作为 AD 疾病进展的生物标志物。我们假设 MR 优化后，PET 差异的影响大小会增加，PET 测量的变异性会减少。