Department of Radiology, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, New York, NY 10021, USA.
AJNR Am J Neuroradiol. 2010 Jun;31(6):1042-8. doi: 10.3174/ajnr.A1989. Epub 2010 Feb 11.
Gd-enhancement provides essential information in the assessment of brain tumors. However, enhancement does not always correlate with histology or disease activity, especially in the setting of current therapies. Our aim was to compare FDG-PET scans to ADC maps and Gd-enhanced MR images in patients with glial neoplasms to assess whether DWI might offer information not available on routine MR imaging sequences and whether such findings have prognostic significance.
Institutional review board approval was obtained for this retrospective review, which was conducted in full compliance with HIPAA regulations. Twenty-one patients (11 men and 10 women) with glial tumors underwent FDG-PET and MR imaging, including ADC and Gd- enhancement. Subjectively, regions of interest were drawn around the following areas: 1) increased FDG uptake, 2) decreased signal intensity on ADC maps, and 3) Gd-enhancement. Objectively, FDG-PET and MR images were co-registered, and pixel-by-pixel comparison of ADC to PET values was made for all regions of interest. Correlation coefficients (r values) were calculated for each region of interest. Percentage overlap between regions of interest was calculated for each case.
Subjective evaluation showed 60% of patients with excellent or good correlation between ADC maps and FDG-PET. Pixel-by-pixel comparison demonstrated r values that ranged from -0.72 to -0.21. There was significantly greater overlap between decreased ADC and increased FDG-PET uptake (67.1 +/- 15.5%) versus overlap between Gd-enhancement and increased FDG-PET uptake (54.4 +/- 27.5%) (P < .05). ADC overlap was greater with increased FDG-PET than with Gd-enhancement in 8/9 cases. Survival data revealed that the presence of restricted diffusion on ADC correlated with patient survival (P < .0001).
ADC maps in patients with brain tumors provide unique information that is analogous to FDG-PET. There is a greater overlap between ADC and FDG-PET compared with Gd-enhancement. ADC maps can serve to approximate tumor grade and predict survival.
钆增强在脑肿瘤评估中提供了重要信息。然而，增强并不总是与组织学或疾病活动相关，特别是在当前治疗的情况下。我们的目的是比较氟脱氧葡萄糖正电子发射断层扫描（FDG-PET）与表观扩散系数（ADC）图和增强磁共振成像（MR）在神经胶质瘤患者中的应用，以评估 DWI 是否可以提供常规 MR 成像序列无法提供的信息，以及这些发现是否具有预后意义。
本回顾性研究获得了机构审查委员会的批准，并且完全符合 HIPAA 法规。21 例（11 名男性和 10 名女性）神经胶质瘤患者接受了 FDG-PET 和 MR 成像，包括 ADC 和 Gd 增强。主观上，在以下区域勾画感兴趣区：1）FDG 摄取增加，2）ADC 图上信号强度降低，3）Gd 增强。客观上，将 FDG-PET 和 MR 图像进行配准，并对所有感兴趣区进行 ADC 与 PET 值的像素对像素比较。计算每个感兴趣区的相关系数（r 值）。计算每个病例的感兴趣区重叠百分比。
主观评估显示，60%的患者 ADC 图与 FDG-PET 具有良好或极好的相关性。像素对像素比较显示 r 值范围为-0.72 至-0.21。与 Gd 增强与 FDG-PET 摄取增加之间的重叠（54.4±27.5%）相比，ADC 降低与 FDG-PET 摄取增加之间的重叠（67.1±15.5%）显著更大（P<.05）。在 8/9 例中，ADC 与 FDG-PET 的重叠大于与 Gd 增强的重叠。生存数据分析显示，ADC 上的弥散受限与患者生存相关（P<.0001）。
脑肿瘤患者的 ADC 图提供了类似于 FDG-PET 的独特信息。与 Gd 增强相比，ADC 与 FDG-PET 之间的重叠更大。ADC 图可用于估计肿瘤分级和预测生存。
