From the Department of Radiology, Shanghai Chest Hospital affiliated to Shanghai Jiaotong University.
Department of Radiology, Shanghai East Hospital affiliated to Tongji University.
J Comput Assist Tomogr. 2021;45(2):269-276. doi: 10.1097/RCT.0000000000001130.
The aims of this retrospective study were to assess the value of the quantitative analysis of apparent diffusion coefficient (ADC) and proton magnetic resonance spectroscopy (1H-MRS) metabolites in differentiating grades of pediatric gliomas.
Two hundred and nine pathology-confirmed pediatric gliomas (143 low-grade gliomas [LGGs] and 66 high-grade gliomas [HGGs]) were retrospectively analyzed on preoperative diffusion-weighted magnetic resonance imaging, of which 84 also underwent 1H-MRS. The mean tumor ADC (ADCmean), minimum tumor ADC (ADCmin), tumor/normal brain ADC ratio (ADC ratio), and metabolites (choline/creatine ratio [Cho/Cr], N-acetylaspartate/creatine ratio [NAA/Cr], N-acetylaspartate/choline ratio [NAA/Cho], presence of lactate and lipid peaks) between LGGs and HGGs were analyzed.
There were significant negative correlations between the ADC values and glioma grade. Receiver operating characteristic analysis showed that the cutoff ADCmean value of 1.192 × 10-3 mm2/s for the differentiation between low- and high-grade pediatric gliomas provided a sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) of 77.6%, 80.3%, 78.5%, 89.5% and 62.4%, respectively; the cutoff ADCmin value of 0.973 × 10-3 mm2/s resulted in a sensitivity, specificity, accuracy, PPV, and NPV of 86.0%, 90.9%, 87.6%, 95.3%, and 75.0%, respectively; the cutoff ADC ratio value of 1.384 resulted in a sensitivity, specificity, accuracy, PPV, and NPV of 73.4%, 87.9%, 78.0%, 92.9%, and 60.4%, respectively. A tendency for a positive correlation was found between Cho/Cr and glioma grade. A negative correlation was demonstrated between NAA/Cr or NAA/Cho and glioma grade. Statistical analysis demonstrated a threshold value of 2.601 for Cho/Cr to provide a sensitivity, specificity, accuracy, PPV, and NPV of 81.8%, 51.7%, 71.4%, 76.3%, and 60.0%, respectively, in dividing LGGs and HGGs; a threshold value of 0.705 for NAA/Cr to provide a sensitivity, specificity, accuracy, PPV, and NPV of 76.4%, 75.9%, 76.2%, 85.7%, and 62.9%, respectively; a threshold value of 0.349 for NAA/Cho to provide a sensitivity, specificity, accuracy, PPV, and NPV of 87.3%, 86.2%, 86.9%, 92.3%, and 78.1%, respectively.
The ADC values and metabolites appeared to be significantly correlated to grade in pediatric gliomas. The predictive values may be helpful for preoperative diagnostic predictions.
本回顾性研究旨在评估表观扩散系数（ADC）定量分析和质子磁共振波谱（1H-MRS）代谢物在区分小儿脑胶质瘤分级中的价值。
对 209 例经病理证实的小儿脑胶质瘤（143 例低级别胶质瘤[LGG]和 66 例高级别胶质瘤[HGG]）进行术前弥散加权磁共振成像分析，其中 84 例还进行了 1H-MRS 检查。分析 LGG 和 HGG 之间的平均肿瘤 ADC（ADCmean）、最小肿瘤 ADC（ADCmin）、肿瘤/正常脑 ADC 比值（ADC ratio）和代谢物（胆碱/肌酸比[Cho/Cr]、N-乙酰天门冬氨酸/肌酸比[NAA/Cr]、N-乙酰天门冬氨酸/胆碱比[NAA/Cho]、乳酸和脂质峰的存在）。
ADC 值与胶质瘤分级呈显著负相关。受试者工作特征分析显示，用于区分低级别和高级别小儿脑胶质瘤的 ADCmean 值截断值为 1.192×10-3mm2/s，其灵敏度、特异性、准确性、阳性预测值（PPV）和阴性预测值（NPV）分别为 77.6%、80.3%、78.5%、89.5%和 62.4%；ADCmin 值截断值为 0.973×10-3mm2/s，灵敏度、特异性、准确性、PPV 和 NPV 分别为 86.0%、90.9%、87.6%、95.3%和 75.0%；ADC ratio 值截断值为 1.384，灵敏度、特异性、准确性、PPV 和 NPV 分别为 73.4%、87.9%、78.0%、92.9%和 60.4%。Cho/Cr 与胶质瘤分级呈正相关趋势。NAA/Cr 或 NAA/Cho 与胶质瘤分级呈负相关。统计分析显示，Cho/Cr 的截断值为 2.601，用于区分 LGG 和 HGG 的灵敏度、特异性、准确性、PPV 和 NPV 分别为 81.8%、51.7%、71.4%、76.3%和 60.0%；NAA/Cr 的截断值为 0.705，灵敏度、特异性、准确性、PPV 和 NPV 分别为 76.4%、75.9%、76.2%、85.7%和 62.9%；NAA/Cho 的截断值为 0.349，灵敏度、特异性、准确性、PPV 和 NPV 分别为 87.3%、86.2%、86.9%、92.3%和 78.1%。
ADC 值和代谢物似乎与小儿脑胶质瘤的分级显著相关。预测值可能有助于术前诊断预测。
