RF-penetrable PET ring for acquiring simultaneous time-of-flight PET and MRI data

项目摘要/摘要（来自母公司申请） 我们建议创建和探索一个射频（RF）穿透正电子发射断层扫描（PET） 系统技术，其可以插入到磁共振成像（MRI）系统中， 同步PET/MRI数据。集成的PET/MRI已经上升到医学成像技术的最前沿， 显示有希望成为疾病表征的有力工具，因为它能够同时测量 身体软组织中的分子、功能和解剖信息。因为这个承诺， 诸如Siemens、GE和Philips的公司已经开发并且现在提供组合的PET/MR系统。 然而，影响这项技术长期影响的挑战之一是目前的成本（500万至600万美元）， 到公司开发集成产品所需的巨大投资，以及用户需要 购买PET和MRI子系统。我们的实验室正在通过创建世界上第一个射频- 可穿透PET环，原则上可插入任何现有MR系统，同时仍允许使用 内置MR RF发射线圈。这将避免将两种模式合并的昂贵费用， 现在，为了实现全身PET/MR，需要对MR系统进行重大修改，包括 重新设计身体发射线圈子系统以驻留在PET环内。因此，所提出的技术 将大大降低现有MR站点升级到PET/MR能力的成本障碍，因为 只需要购买RF透射PET插入物，也可以减少行业投资 实现PET/MRI一体化。 假设：使用所提出的新颖的电光信号传输方案，我们可以创建一个 PET插入物可穿透RF场，因此可以使用 MR系统的内置体发射线圈。使PET环插入件能够被RF- 可穿透的（即，RF场泄漏到PET环内部）是使其相对于PET环电浮动。 MR系统，并且在PET探测器模块之间具有场线可能泄漏的小间隙。这 浮动PET环通过“电光”信号传输的概念成为可能， 电信领域;在我们的配方中，快速闪烁探测器信号耦合到微小的 激光，转换成近红外光，并通过长的光纤传输， 从而能够与MR系统电隔离。此外，由于电光方法使用 光纤，与PET系统相比，它大大减少了MR系统内的电气足迹 使用长电缆的设计，同时实现出色的空间、能量和时间分辨率 需要PET。在这个项目中，我们将开发一个完整的证明，这一射频穿透的概念， 通过大脑大小的PET插入物，并在3 T MRI系统中测试其射频传输。为了实现这些 为了实现这些目标，我们探索了许多创新概念。

Project Summary / Abstract (from parent application) We propose to create and explore a radio-frequency (RF)-penetrable positron emission tomography (PET) system technology that can be inserted into a magnetic resonance imaging (MRI) system for acquiring simultaneous PET/MRI data. Integrated PET/MRI has risen to the cutting edge of medical imaging technology, showing promise to be a powerful tool in disease characterization as it enables the simultaneous measurement of molecular, functional, and anatomical information in soft tissues of the body. Because of this promise, companies such as Siemens, GE, and Philips have developed and are now offering combined PET/MR systems. However, one of the challenges affecting the long-term impact of this technology is the current cost ($5-6M) due to the huge investment required by a company to develop an integrated product, and the need for the user to purchase both PET and MRI sub-systems. Our lab is addressing these issues by creating the world’s first RF- penetrable PET ring, which can in principle be inserted into any existing MR system, while still allowing use of the built-in MR RF transmit coil. This would avoid the expensive integration of the two modalities, which, up to now, in order to achieve whole-body PET/MR, has required substantial modifications to the MR system, including re-engineering the body transmit coil sub-system to reside inside the PET ring. Thus, the proposed technology would substantially lower the cost barrier for an existing MR site to upgrade to PET/MR capability since they would just need to purchase the RF-transmissive PET insert, and it also would reduce the industry investment to achieve integrated PET/MRI. Hypothesis: Using the novel electro-optical signal transmission scheme proposed, we can create a PET insert that is penetrable to a RF field and thus can achieve simultaneous ToF-PET/MR using the built in body transmit coil of an MR system. The basic idea to enable the PET ring insert to be RF- penetrable (i.e. for the RF field to leak inside of the PET ring) is to have it electrically floating with respect to the MR system, and to have small gaps between PET detector modules where the field lines can leak in. This floating PET ring is made possible via the concept of “electro-optical” signal transmission, which draws from the field of telecommunications; in our formulation, the fast scintillation detector signals are coupled to tiny lasers, converted to near infrared light, and transmitted down long telecommunications-grade optical fibers, thus enabling electrical isolation from the MR system. In addition, since the electro-optical approach uses optical fibers, it substantially reduces the electrical footprint within the MR system compared to a PET system design that uses long electrical cables, while achieving excellent spatial, energy, and temporal resolutions required for PET. In this project, we will develop a full proof-of-principle of this RF-penetrable concept via a brain-size PET insert, and test its RF transmissivity in a 3T MRI system. In order to achieve these goals, we explore many innovative concepts.