Bell Christopher, Rose Stephen, Puttick Simon, Pagnozzi Alex, Poole Christopher M, Gal Yaniv, Thomas Paul, Fay Michael, Jeffree Rosalind L, Dowson Nicholas
CSIRO Preventative Health Flagship, CSIRO Computational Informatics, The Australian e-Health Research Centre, Herston QLD 4029, Australia. School of Medicine, The University of Queensland, St Lucia, Brisbane, Australia.
Phys Med Biol. 2014 Jul 21;59(14):3925-49. doi: 10.1088/0031-9155/59/14/3925. Epub 2014 Jun 24.
Metabolic imaging using positron emission tomography (PET) has found increasing clinical use for the management of infiltrating tumours such as glioma. However, the heterogeneous biological nature of tumours and intrinsic treatment resistance in some regions means that knowledge of multiple biological factors is needed for effective treatment planning. For example, the use of (18)F-FDOPA to identify infiltrative tumour and (18)F-FMISO for localizing hypoxic regions. Performing multiple PET acquisitions is impractical in many clinical settings, but previous studies suggest multiplexed PET imaging could be viable. The fidelity of the two signals is affected by the injection interval, scan timing and injected dose. The contribution of this work is to propose a framework to explicitly trade-off signal fidelity with logistical constraints when designing the imaging protocol. The particular case of estimating (18)F-FMISO from a single frame prior to injection of (18)F-FDOPA is considered. Theoretical experiments using simulations for typical biological scenarios in humans demonstrate that results comparable to a pair of single-tracer acquisitions can be obtained provided protocol timings are carefully selected. These results were validated using a pre-clinical data set that was synthetically multiplexed. The results indicate that the dual acquisition of (18)F-FMISO and (18)F-FDOPA could be feasible in the clinical setting. The proposed framework could also be used to design protocols for other tracers.
使用正电子发射断层扫描（PET）的代谢成像在胶质瘤等浸润性肿瘤的管理中已得到越来越多的临床应用。然而，肿瘤的异质生物学性质以及某些区域固有的治疗抗性意味着有效的治疗规划需要了解多种生物学因素。例如，使用（18）F - FDOPA识别浸润性肿瘤，使用（18）F - FMISO定位缺氧区域。在许多临床环境中进行多次PET采集是不切实际的，但先前的研究表明多路复用PET成像可能是可行的。两种信号的保真度受注射间隔、扫描时间和注射剂量的影响。这项工作的贡献在于提出一个框架，在设计成像方案时明确权衡信号保真度与后勤限制。考虑了在注射（18）F - FDOPA之前从单帧估计（18）F - FMISO的特殊情况。使用针对人类典型生物学场景的模拟进行的理论实验表明，只要仔细选择方案时间，就可以获得与一对单示踪剂采集相当的结果。这些结果使用合成多路复用的临床前数据集进行了验证。结果表明，在临床环境中同时采集（18）F - FMISO和（18）F - FDOPA可能是可行的。所提出的框架也可用于设计其他示踪剂的方案。
