Abstract：
Perfusion dynamics play a vital role in delivering essential nutrients and oxygen to tissues while removing metabolic waste products. Imaging techniques such as magnetic resonance imaging (MRI), computed tomography (CT), and positron emission tomography (PET) use contrast agents to visualize perfusion and clearance patterns; however, each technique has specific limitations. Hybrid PET/MRI combines the quantitative power and sensitivity of PET with the high functional and anatomical detail of MRI and holds great promise for precision in molecular imaging. However, the development of dual PET/MRI probes has been hampered by challenging synthesis and radiolabeling. Here, we present a novel PET/MRI probe, [18F][Gd(FL1)], which exhibits excellent stability comparable to macrocyclic MRI contrast agents used in clinical practice. The unique molecular design of [18F][Gd(FL1)] allows selective and expeditious radiolabeling of the gadolinium chelate in the final synthetic step. Leveraging the strengths of MRI and PET signals, the probe enables quantitative in vivo mapping of perfusion and excretion dynamics through an innovative voxel-based analysis. The diagnostic capabilities of [18F][Gd(FL1)] were demonstrated in a pilot study on healthy mice, successfully detecting early cases of unilateral renal dysfunction. This study introduces a new approach for PET/MRI and emphasizes a streamlined probe design for improved diagnostic accuracy.
摘要：
灌注动力学在向组织输送必需营养素和氧气同时去除代谢废物中起着至关重要的作用。成像技术，如磁共振成像（MRI），计算机断层扫描（CT），和正电子发射断层扫描（PET）使用造影剂来可视化灌注和清除模式；然而，每种技术都有特定的局限性。混合PET/MRI将PET的定量功率和灵敏度与MRI的高功能和解剖学细节相结合，并在分子成像中具有很好的精度。然而,具有挑战性的合成和放射性标记阻碍了双PET/MRI探针的开发。这里,我们提出了一种新型的PET/MRI探头，[18F][Gd(FL1)],与临床实践中使用的大环MRI造影剂相比，具有出色的稳定性。[18F][Gd(FL1)]的独特分子设计允许在最终合成步骤中选择性和迅速地放射性标记钆螯合物。利用MRI和PET信号的优势，该探针能够通过创新的基于体素的分析定量体内灌注和排泄动力学作图。在对健康小鼠的初步研究中证明了[18F][Gd（FL1）]的诊断能力，成功发现早期单侧肾功能不全病例。这项研究为PET/MRI引入了一种新方法，并强调了简化的探头设计，以提高诊断准确性。
