Ouyang Yu, Judenhofer Martin S, Walton Jeffrey H, Marik Jan, Williams Simon P, Cherry Simon R
Department of Biomedical Engineering, University of California, Davis;
Department of Biomedical Engineering, University of California, Davis.
J Vis Exp. 2015 Sep 20(103):52728. doi: 10.3791/52728.
Dynamic changes in tissue water diffusion and glucose metabolism occur during and after hypoxia in cerebral hypoxia-ischemia reflecting a bioenergetics disturbance in affected cells. Diffusion weighted magnetic resonance imaging (MRI) identifies regions that are damaged, potentially irreversibly, by hypoxia-ischemia. Alterations in glucose utilization in the affected tissue may be detectable by positron emission tomography (PET) imaging of 2-deoxy-2-(18F)fluoro-ᴅ-glucose ([18F]FDG) uptake. Due to the rapid and variable nature of injury in this animal model, acquisition of both modes of data must be performed simultaneously in order to meaningfully correlate PET and MRI data. In addition, inter-animal variability in the hypoxic-ischemic injury due to vascular differences limits the ability to analyze multi-modal data and observe changes to a group-wise approach if data is not acquired simultaneously in individual subjects. The method presented here allows one to acquire both diffusion-weighted MRI and [18F]FDG uptake data in the same animal before, during, and after the hypoxic challenge in order to interrogate immediate physiological changes.
在脑缺氧缺血期间及之后，组织水扩散和葡萄糖代谢会发生动态变化，这反映了受影响细胞中的生物能量学紊乱。扩散加权磁共振成像（MRI）可识别因缺氧缺血而受到潜在不可逆损伤的区域。通过对2-脱氧-2-（18F）氟-D-葡萄糖（[18F]FDG）摄取进行正电子发射断层扫描（PET）成像，可检测受影响组织中葡萄糖利用的变化。由于该动物模型中损伤的快速性和变异性，必须同时采集这两种数据模式，以便有意义地关联PET和MRI数据。此外，如果不在个体受试者中同时采集数据，由于血管差异导致的缺氧缺血损伤的动物间变异性会限制分析多模态数据并以分组方式观察变化的能力。本文介绍的方法允许在缺氧挑战之前、期间和之后在同一动物中采集扩散加权MRI和[18F]FDG摄取数据，以便探究即时的生理变化。
