Ertl-Wagner B, Ingrisch M, Niyazi M, Schnell O, Jansen N, Förster S, la Fougère C
Institut für Klinische Radiologie, Klinikum der Ludwig-Maximilians-Universität, Campus Großhadern, Marchioninistr. 15, 81377 München, Deutschland.
Radiologe. 2013 Aug;53(8):682-90. doi: 10.1007/s00117-013-2500-y.
Glioblastoma multiforme (GBM) is the most common and most aggressive primary tumor of the brain. In recent years newer therapeutic approaches have been developed. To allow for an optimized treatment planning it is important to precisely delineate necrotic tissue, edema and vital tumor tissue and to identify the most aggressive parts of the GBM. The magnetic resonance (MR) portion of an MR-positron emission tomography (PET) examination in patients with GBM should consist of both structural and functional sequences including diffusion-weighted and perfusion sequences. The use of (18)F-fluorodeoxyglucose ((18)F-FDG) is limited in patients with gliomas as glucose metabolism is already physiologically high in parts of the brain but (18)F-FDG is nevertheless a commonly used radiopharmaceutical for neuro-oncological questions. (18)F-fluorothymidine reflects the cellular activity of thymidine kinase 1 and correlates with the expression of KI-67 as an index of mitotic activity. The nitroimidazole derivatives (18)F-fluoromisonidazole and (18)F-fluoroazomycin arabinoside ((18)F-FAZA) allow the detection of hypoxic areas within the tumor. In recent years amino acid tracers, such as (18)F-fluoroethyltyrosine are increasingly being used in the diagnosis of gliomas. The simultaneous PET-MR image acquisition allows new approaches, e.g. motion correction by the simultaneous acquisition of MR data with a high temporal resolution and an improved quantification of the PET signal by integrating the results of functional MR sequences. Moreover, the simultaneous acquisition of these two time-consuming methods leads to reduced imaging times for this, often severely ill patient group.
多形性胶质母细胞瘤（GBM）是最常见且侵袭性最强的原发性脑肿瘤。近年来已开发出更新的治疗方法。为了实现优化的治疗方案规划，精确勾勒坏死组织、水肿和存活肿瘤组织，并识别GBM中最具侵袭性的部分非常重要。GBM患者的磁共振成像（MR）部分的正电子发射断层扫描（PET）检查应包括结构和功能序列，包括扩散加权序列和灌注序列。（18）F-氟脱氧葡萄糖（（18）F-FDG）在胶质瘤患者中的应用有限，因为大脑部分区域的葡萄糖代谢在生理上已经很高，但（18）F-FDG仍然是用于神经肿瘤学问题的常用放射性药物。（18）F-氟胸苷反映胸苷激酶1的细胞活性，并与作为有丝分裂活性指标的KI-67表达相关。硝基咪唑衍生物（18）F-氟米索硝唑和（18）F-氟阿糖胞苷（（18）F-FAZA）可检测肿瘤内的缺氧区域。近年来，氨基酸示踪剂，如（18）F-氟乙基酪氨酸越来越多地用于胶质瘤的诊断。PET-MR图像的同时采集允许采用新方法，例如通过以高时间分辨率同时采集MR数据进行运动校正，并通过整合功能MR序列的结果来改进PET信号的定量。此外，同时采集这两种耗时的方法可减少这一通常病情严重的患者群体的成像时间。
