Xing Z, You R X, Li J, Liu Y, Cao D R
Department of Radiology, First Affiliated Hospital, Fujian Medical University, 20 Cha-Zhong Road, 350005, Fuzhou, Fujian, P.R. China.
Clin Neuroradiol. 2014 Dec;24(4):329-36. doi: 10.1007/s00062-013-0255-5. Epub 2013 Aug 31.
Primary central nervous system lymphoma (PCNSL) and high-grade glioma (HGG) may have similar enhancement patterns on magnetic resonance imaging (MRI), making the differential diagnosis difficult or even impractical. Relative cerebral blood volume (rCBV) and percentage of signal intensity recovery derived from dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR imaging may help distinguish PCNSL from HGG. The purpose of this study was to evaluate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of these two imaging parameters used alone or in combination for differentiating PCNSL from HGG.
A total of 12 patients with PCNSL and 26 patients with HGG were examined using a 3T scanner. rCBV and percentage of signal intensity recovery were obtained and receiver operating characteristic (ROC) analysis was performed to determine optimum thresholds for tumor differentiation. Sensitivity, specificity, PPV, NPV, and accuracy for identifying the tumor types were also calculated.
The optimum threshold of 2.56 for rCBV provided sensitivity, specificity, PPV, NPV, and accuracy of 96.2, 90, 92.6, 94.7, and 93.5%, respectively, for determining PCNSL. A threshold value of 0.89 for percentage of signal intensity recovery optimized differentiation of PCNSL and HGG with a sensitivity, specificity, PPV, NPV, and accuracy of 100, 88.5, 87, 100, and 93.5%, respectively. Combining rCBV with the percentage of signal intensity recovery further improved the differentiation of PCNSL and HGG with a specificity of 98.5% and an accuracy of 95.7%.
The combination of rCBV measurement with percentage of signal intensity recovery can help in more accurate differentiation of PCNSL from HGG.
原发性中枢神经系统淋巴瘤（PCNSL）和高级别胶质瘤（HGG）在磁共振成像（MRI）上可能具有相似的强化模式，这使得鉴别诊断困难甚至无法实现。相对脑血容量（rCBV）和动态磁敏感对比增强（DSC）灌注磁共振成像得出的信号强度恢复百分比可能有助于区分PCNSL和HGG。本研究的目的是评估单独或联合使用这两个成像参数区分PCNSL和HGG的敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）及准确性。
使用3T扫描仪对12例PCNSL患者和26例HGG患者进行检查。获取rCBV和信号强度恢复百分比，并进行受试者操作特征（ROC）分析以确定肿瘤鉴别的最佳阈值。还计算了识别肿瘤类型的敏感性、特异性、PPV、NPV和准确性。
rCBV的最佳阈值为2.56，在确定PCNSL时，其敏感性、特异性、PPV、NPV和准确性分别为96.2%、90%、92.6%、94.7%和93.5%。信号强度恢复百分比的阈值为0.89时，优化了PCNSL和HGG的鉴别，其敏感性、特异性、PPV、NPV和准确性分别为100%、88.5%、87%、100%和93.5%。将rCBV与信号强度恢复百分比相结合进一步改善了PCNSL和HGG的鉴别，特异性为98.5%，准确性为95.7%。
rCBV测量与信号强度恢复百分比相结合有助于更准确地区分PCNSL和HGG。
