MR-PET für die Medizinische Bildgebung

为响应DFG对PET-MR扫描系统的呼吁，“Leipzig Combined PET-MRI”（Leipzig X Combined PET-MRT， LEXPERT）倡议正在寻求资金。LEXPERT组建了一个由国际知名PET和MRI成像研究人员组成的跨学科联盟。莱比锡大学医院核医学（NUK）、诊断和介入放射学（RAD）、神经放射学（NEU）、儿科放射学（PED）和认知神经病学，马克斯普朗克人类认知和脑科学研究所（MPI）神经内科，莱比锡大学/莱比锡心脏中心（HZL）诊断和介入放射学，以及莱比锡弗劳恩霍夫细胞治疗和免疫研究所（IZI）。因此，我们可以利用广泛的PET和MR成像专业知识来解决广泛的研究课题，从临床前动物模型到免疫学、神经外科、儿科学、神经精神病学、肿瘤学和心脏病学的临床应用。对于许多研究问题，结合序列PET、fMRI和/或MRI获得的功能和形态成像信息已经成为一种标准程序，因为基于软件的共配准算法可以获得足够的共配准精度。然而，当一种成像方式（如PET）的发现必须与另一种成像方式（如fMRI）定义的某种（如功能）状态直接相关时，同时进行PET- mr成像就变得至关重要。因此，我们和其他人相信PET-MRI结合的独特潜力可以大大提高基础和临床研究的医学成像能力。LEXPERT将专注于这些科学问题，同时获取各自的成像数据是提高诊断的关键。使用新的组合成像技术进行的脑研究包括基础研究应用，旨在(i)通过同时进行EEG， fMRI和PET测量建立“多模态脑状态神经成像”，以及（ii）通过比较灌注PET对BOLD fMRI对比进行定量验证。临床前大型动物和临床试验计划用于（iii）测量尼古丁对成瘾和痴呆的神经递质/脑状态的影响，（iv）调查影响情绪的激素变化对血清素能和一般脑功能的影响，(v)验证目前在急性期临床常规中的脑卒中- mr概念，（vi）提高对急性卒中缺血性半暗带的理解、成像和治疗。（vii）同时追踪干细胞并监测其在中风中的治疗效果，以及（viii）同时评估动脉瘤性蛛网膜下腔出血的脑代谢和循环。在肿瘤影像学方面，将研究宫颈癌，作为建立全身PET-MRI联合的模型，以改善肿瘤的原发或复发分期以及治疗监测。该模型被选为基于宫颈癌肿瘤分期在空间共配准方面的极端挑战的同步设计中的第一个模型，这在传统的顺序成像设计中通常是有限的。我们预测，宫颈癌的进展可以转移到其他肿瘤实体。进一步，我们的目的是研究联合PET-MRI的诊断潜力，以及麻醉和减轻辐射负担的程度对患有霍奇金病、骨恶性肿瘤和尤因肉瘤的儿童（与连续全身PET-CT和MR成像相比）。在心脏研究中，联合PET- mri将用于(i)同时成像冠状动脉形态和炎症，以在疾病早期识别易损斑块患者，（ii）改善心肌炎的诊断，以及（iii）验证测量心肌灌注与PET金标准的概念。莱比锡大学医院和莱比锡大学医学院全力支持LEXPERT的科学专业知识，以最大限度地提高PET-MR扫描仪在莱比锡的临床影响。安装联合PET-MRI系统所需的基础设施的第一个里程碑已经实现。莱比锡大学医院/莱比锡大学医学院明确承诺支付后续支出，并将从PET和MRI扫描仪的合作伙伴以及图像处理软件和放射性示踪剂制造行业获得额外资金。为了优化PET-MRI联合系统的利用，已经开发了一个直接的用户概念，这将允许对该领域感兴趣的“内部”和“外部”科学家访问，并促进国际合作。我们相信，LEXPERT不仅满足了成功运行联合PET-MRI系统的所有科学和基础设施先决条件，而且我们共同制定了一个独特而雄心勃勃的研究议程，以确保进一步的前沿方法开发，可靠的科学验证研究和临床试验，以及探索同步PET-MRI技术的引人注目的创新应用。

In response to the DFG call for a PET-MR scanning system, the “Leipzig Combined PET-MRI” (LEipzig X combined PET-MRT, LEXPERT) initiative seeks funding. LEXPERT assembles an interdisciplinary consortium of internationally renowned PET and MRI imaging researchers from the Depts. of Nuclear Medicine (NUK), Diagnostic and Interventional Radiology (RAD), Neuroradiology (NEU), Pediatric Radiology (PED), and Cognitive Neurology at the University Hospital Leipzig, the Dept. of Neurology at the Max Planck Institute for Human Cognitive and Brain Sciences (MPI), the Dept. of Diagnostic and Interventional Radiology at the University Leipzig / Heart Center Leipzig (HZL), and the Fraunhofer Institute for Cell Therapy and Immu-nology Leipzig (IZI). As such, we can draw from a broad PET and MR imaging expertise to ad-dress a wide spectrum of research topics ranging from preclinical animal models to clinical ap-plications in immunology, neurosurgery, pediatrics, neuropsychiatry, oncology and cardiology. For many research questions, combining functional and morphological imaging information as obtained by sequential PET, fMRI and/or MRI has already been established as a standard procedure since sufficient precision of coregistration can be obtained with software-based co-registration algorithms. However, when a finding in one imaging modality (e.g. PET) must be directly related to a certain (e.g. functional) state as defined by the other modality (e.g. fMRI), simultaneous PET-MR imaging becomes crucial. Therefore, we and others believe in the unique potential of combined PET-MRI to substantially advance the medical imaging repertoire avail-able for basic and clinical research. LEXPERT will focus on those scientific questions, for which simultaneous acquisition of the respective imaging data is key to improve diagnostics. Brain studies to be performed with the new combined imaging technique comprise basic re-search applications aiming at (i) establishing a “multimodal brain state neuroimaging“ with simul-taneous EEG, fMRI, and PET measurements and (ii) quantitative validation of BOLD fMRI con-trast by comparative perfusion PET. Preclinical large animal and clinical testing is planned for (iii) measuring the neurotransmitter / brain state effects of nicotine on addiction and dementia, (iv) investigating mood-affecting hormonal changes on serotonergic and general brain function, (v) verifying the stroke-MR concept currently in clinical routine in acute stage, (vi) improving the understanding, imaging and treatment of the ischemic penumbra in acute stroke, (vii) simulta-neously tracing stem cells and monitoring their treatment effects in stroke, as well as for (viii) simultaneously assessing cerebral metabolism and circulation in aneurysmal subarachnoid hemorrhage. In the area of tumor imaging, cervical cancer will be investigated as a model for the estab-lishment of combined whole-body PET-MRI to improve primary or recurrence tumor staging as well as therapy monitoring. This model was chosen to be the first in a simultaneous design based on the extreme challenge tumor-staging of cervical cancer poses in terms of spatial co-registration that is often limited in conventional sequential imaging design. We predict that pro-gress achieved for cervical cancer can then be transferred to other tumor entities. Further we aim to investigate the diagnostic potential of combined PET-MRI and the degree of anesthesia and radiation burden reduction for children suffering from Hodgkin’s disease, bone malignan-cies, and Ewing sarcoma (as compared to sequential whole-body PET-CT and MR imaging). In cardiac research, combined PET-MRI will be applied to (i) simultaneously image coronary artery morphology and inflammation to identify patients with vulnerable plaques at an early stage of disease, (ii) improve diagnosis of myocarditis, and to (iii) verify the concept of measur-ing myocardial perfusion versus the PET gold standard. The scientific expertise of LEXPERT is met with full commitment of the Leipzig University Hospital and the Medical Faculty of the Leipzig University to maximize the clinical impact of the PET-MR scanner in Leipzig. The first milestones of setting up the infrastructure required to in-stall a combined PET-MRI system have already been achieved. There is a clear financial com-mitment of the University Hospital Leipzig / Medical Faculty of the Leipzig University to cover follow-up expenditures, and additional funding will be secured from partners of the PET and MRI scanner, as well as image processing software and radiotracer manufacturing industry. To optimize the utilization of a combined PET-MRI system, a straight-forward user concept has been developed, which will allow access to “internal” and “external” scientists interested in this field and foster international collaboration. We are convinced that LEXPERT does not only meet all scientific and infrastructural prereq-uisites to successfully run a combined PET-MRI system, but that we have jointly developed a unique and ambitious research agenda to secure further cutting edge methodological develop-ment, solid scientific validation studies and clinical testing, and the exploration of compelling innovative applications of the simultaneous PET-MRI technique.