PET Insert for MAGNETOM Trio

描述(由申请人提供)：这项提案要求为新推出的高分辨率PET断层扫描插入物提供资金，以生产一种混合MR/PET系统，从而能够真正同时采集人体受试者的PET和MR脑成像数据。PET插件将与现有的3T西门子Trio磁共振系统(它是专门为之设计的)结合在一起。由此产生的MR/PET混合系统将作为共享资源提供给匹兹堡大学和其他当地机构的研究人员。该大学内将受益于该仪器的系包括：精神病学、放射学和放射肿瘤学、物理医学和康复、神经病学和神经外科、病理学和耳鼻喉科。该系统将设在匹兹堡大学磁共振研究中心，并将由一个内部咨询委员会管理和指导，该委员会由本提案中确定的联合调查员和主要用户组成。该插件使用新的PET探测器技术，使用磁性不敏感的雪崩光电二极管(APD)而不是光电倍增管(PMT)，并由一个适合MR孔内的探测器环组成。在小动物成像的临床前系统中，将APDS用于MR兼容的PET已被确立。该插入物比目前用于人脑PET成像的仪器性能更好，并且可以在高磁场环境中操作，而不会显著影响MR系统的性能。MR图像可用于对PET数据进行衰减校正，使得不存在与此目的相关的电离辐射，这与PET或PET/CT成像的情况不同。该系统将提供在空间和时间域与解剖和功能磁共振数据集(fMRI、DTI、光谱学)内在地共同注册的PET数据集。我们预计该系统将显著加强研究的领域包括：1)功能和生理验证范例(例如，BOLD MR信号与[150]H2O PET脑血流)。2)表征认知功能(FMRI)与治疗药物和/或急性药物挑战(PET)的神经感受器占有率之间的关系。3)对重症监护或短暂疾病(如中风、癫痫、多发性硬化症)的研究，其高度动态的生理学需要同时进行解剖和功能评估。4)精确的脑和头颈部肿瘤的解剖勾画和同步功能评估，用于放射治疗计划，以及对解剖和功能肿瘤反应的纵向评估。5)在基于图谱的脑区划分、组织分类/分割和体积评估方面，更精确地应用结构磁共振结果。多模式MR/PET系统的引入预计将对研究神经科学和肿瘤放射治疗计划和反应评估产生广泛影响。确定了11个主要用户、由美国国立卫生研究院资助的匹兹堡大学研究项目，这些项目将立即受益于这种新的多模式技术。 公共卫生相关性：

DESCRIPTION (provided by applicant): This proposal requests funds for a newly available high resolution PET tomograph insert to produce a hybrid MR/PET system allowing true simultaneous acquisition of PET and MR brain imaging data in human subjects. The PET insert will be combined with an existing 3T Siemens TRIO MR system (for which it is specifically designed). The resulting hybrid MR/PET system will be available as a shared resource to researchers at the University of Pittsburgh and other local institutions. Departments within the University that that will benefit from the instrument include: Psychiatry, Radiology & Radiation Oncology, Physical Medicine & Rehabilitation, Neurology & Neurosurgery, Pathology, and Otolararyngology. The system will be sited in the University of Pittsburgh Magnetic Resonance Research Center and will be managed and directed by an Internal Advisory Committee composed of the co-investigators and major users identified in this proposal. The insert uses new PET detector technology, with magnetically insensitive avalanche photodiodes (APDs) in favor of photo-multiplier tubes (PMTs), and consists of a detector ring that fits inside the MR bore. The use of APDs for MR-compatible PET is established in pre-clinical systems for small animal imaging. The proposed insert performs better than present instrumentation for human brain PET imaging, and can operate within the high magnetic field environment without significantly affecting the performance of the MR system. The MR images may be used for attenuation correction of the PET data such that no ionizing radiation is associated with this purpose, as is not the case for PET or PET/CT imaging. The system will provide PET datasets that are intrinsically co-registered with anatomical and functional MR datasets (fMRI, DTI, spectroscopy) in both spatial and temporal domains. Areas where we expect the system to significantly enhance investigational research are: 1) Functional and physiologic validation paradigms (e.g. BOLD MR signal vs. [15O]H2O PET cerebral blood flow). 2) Characterization of the relationship between cognitive function (fMRI) and neuroreceptor occupancy by therapeutic agents and/or an acute pharmacologic challenge (PET). 3) Studies in critical care or ephemeral conditions (e.g. stroke, epilepsy, MS), for which the highly dynamic physiology demands simultaneous anatomical and functional assessments. 4) Precise anatomic delineation and simultaneous functional assessment of brain and head-and-neck tumors for radiation treatment planning, as well as longitudinal assessments of anatomic and functional tumor response. 5) More precise application of structural MR results with respect to atlas-based delineation of brain regions, tissue classification/segmentation, and volumetric assessments. The introduction of multimodality MR/PET systems is expected to have a broad impact on investigational neuroscience and radiation treatment planning and assessment of response in oncology. 11 Major User NIH-funded research projects at the University of Pittsburgh that will immediately benefit from this new multimodality technology are identified. PUBLIC HEALTH RELEVANCE: