MicroPET-MR scanner for preclinical molecular imaging

描述(由申请人提供)：本提案申请资助购买Sedecal Inc.制造的超级Argus正电子发射断层扫描-磁共振(PET-MR)成像系统，用于临床前小动物多模式成像，以支持马萨诸塞州综合医院(MGH)放射科的研究工作。该设备是美国第一个商用的临床前microPET-MR系统，完全集成了最先进的高分辨率PET和最先进的高分辨率磁共振功能。该系统的横轴视场为68毫米的两个组成部分，允许小鼠和大鼠成像。PET采集具有亚毫米的空间分辨率，是任何商业系统中每片最高的灵敏度，并且具有很高的一致性。优化的算法使得3D OSEM的快速重建时间不到2分钟，而滤波反投影的重建时间不到5秒。MR采集模块基于一种新型的无冷媒设计，超导3T磁体，磁梯度强度为125mT/m。该系统具有用于PET和MR采集的集成图形用户界面。这款扫描仪将极大地加强NIH资助的不同研究人员的研究努力。该系统将为磁共振试剂和PET放射性示踪剂分布的无创连续评估提供高分辨率多模式成像能力，以促进新型多模式分子示踪剂的研究；提供高分辨率相关解剖磁共振图像，以早期评估根据亚器官水平测量的放射性示踪剂摄取变化评估的新疗法的疗效；并提供测试新型多模式动力学建模和改进的图像重建算法的平台。与单独的PET和MR设备相比，该系统在啮齿动物成像方面具有三大优势。首先，如果需要在成像系统之间移动动物，则组合设备可以实现两种模式的时间分辨率；这对于多模式代理开发和多模式动力学建模都是至关重要的。其次，通过一个组合系统，空间共定位得到了极大的改善，这对于大脑受体研究和评估基因工程小鼠疾病模型至关重要。第三，吞吐量大大提高，无需在系统之间移动动物，从而改进了数据收集。该应用程序包含的项目包括代表不同学科(放射学/核医学、化学/放射化学、肿瘤学、神经学、基因工程小鼠建模、动力学建模、图像重建、治疗性干细胞输送和组织工程)和NIH资金来源(NCI、NIBIB、NHLBI、NINDS、NIDA、NIMH、NIAMS)的广泛用户基础。必要的行政和技术指导已经到位，以确保该仪器的有效利用。这将是大波士顿地区第一个这样的系统，无论是商业还是其他方面。它将提供一个平台来测试开发的试剂和成像范例，这些药物和成像范例将补充MGH的人类PET-MR努力，并将成为该地区由NIH资助的大型研究人员的主要资产。

DESCRIPTION (provided by applicant): This proposal requests funding for the purchase of a Super Argus Positron Emission Tomography-Magnetic Resonance (PET-MR) imaging system made by Sedecal Inc. for preclinical small animal multimodal imaging to support the research efforts in the Department of Radiology at the Massachusetts General Hospital (MGH). The device is the first commercial preclinical microPET-MR system available in the United States, and has fully integrated state-of-the-art high-resolution PET and state-of-the-art high-resolution MR capabilities. The system transaxial field of view is 68 mm for both components allowing both mouse and rat imaging. The PET acquisition has sub-millimeter spatial resolution, the highest sensitivity per slice of any commercial system, and high uniformity. Optimized algorithms result in rapid reconstruction of less than 2 min for 3D OSEM and less than 5 sec for filtered back projection. The MR acquisition module is based on a novel cryogen-free design, superconducting 3T magnet, with magnetic gradient strength of 125mT/m. The system has an integrated graphical user interface for both PET and MR acquisitions. This scanner will significantly enhance the research efforts of a diverse group of NIH funded investigators. The system will provide high-resolution multimodal imaging capabilities for non-invasive serial evaluation of MR agent and PET radiotracer distribution to facilitate research in new multimodal molecular tracers; provide high resolution correlative anatomic MR images for early assessment of response to novel therapies evaluated with changes in radiotracer uptake measured at the sub-organ level; and provide a platform for testing novel multimodality kinetic modeling and improved image reconstruction algorithms. The system has three major advantages over separate PET and MR devices for rodent imaging. First, the combined device can achieve temporal resolution for both modalities not attainable if animals are required to be moved between imaging systems; this is vital for both multimodal agent development and multimodal kinetic modeling. Second, spatial co-localization is greatly improved with a combined system, which is vital for brain receptor studies and assessment of genetically engineered mouse models of disease. Third, throughput is greatly enhanced without the need to move animals between systems, improving data collection. The application contains projects that comprise a broad base of users representing various disciplines (radiology/nuclear medicine, chemistry/radiochemistry, oncology, neurology, genetically engineered mouse modeling, kinetic modeling, image reconstruction, therapeutic stem cell delivery, and tissue engineering) and NIH funding sources (NCI, NIBIB, NHLBI, NINDS, NIDA, NIMH, NIAMS).The necessary administrative and technical direction is already in place to ensure efficient utilization of this instrumentation. This will be the first such system, commercial or otherwise, in the greater Boston area. It will provide a platform to test developed agents and imaging paradigms that will complement the human PET-MR efforts at MGH, and will be major asset to a large community of NIH funded investigators in the region.