Liao Weihua, Liu Yunhai, Wang Xiaoyi, Jiang Xinya, Tang Beisha, Fang Jiasheng, Chen Changqing, Hu Zhongliang
Department of Radiology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
Acta Radiol. 2009 Mar;50(2):217-25. doi: 10.1080/02841850802616752.
Preoperative differentiation of primary central nervous system lymphomas (PCNSLs) from other tumors is important for presurgical staging, intraoperative management, and postoperative treatment. Dynamic susceptibility contrast-enhanced perfusion magnetic resonance imaging (DSC perfusion MRI) can provide in vivo assessment of the microvasculature in intracranial mass lesions.
To determine the utility of DSC perfusion MRI in the differentiation of PCNSLs and high-grade gliomas, as well as their pathological and physiological differences.
Nine patients with pathologically proven PCNSLs and 11 patients with high-grade gliomas were examined using a 1.5 T MRI scanner. DSC perfusion MRI was performed by gradient-echo echo-planar imaging (GE-EPI). The maximum rCBV ratio, the signal intensity-time curves, and the percentage of signal intensity recovery were obtained. The maximum relative cerebral blood volume (rCBV) ratio and the percentage of signal intensity recovery of PCNSLs were compared with those of high-grade gliomas by using Student's t test. Microvessel density (MVD) was evaluated using immunohistochemical staining of surgical specimens with anti-CD34, and MVDs of the two tumor groups were compared by using Student's t test.
The maximum rCBV ratio of primary intracranial lymphomas was 1.72+/-0.59, while that of high-grade gliomas was 4.86+/-2.18. PCNSLs tended to have relatively low perfusion compared to high-grade gliomas (P=0.001), and the MVD labeled by anti-CD34 of PCNSLs was much lower than that of gliomas (P<0.001). The signal intensity-time curve of primary intracranial lymphomas was different from that of high-grade gliomas. The percentage of signal intensity recovery was significantly greater in PCNSLs compared with that of high-grade gliomas (P<0.001).
The difference in DSC perfusion MRI characteristics between PCNSLs and high-grade gliomas is determined by their different vascularities and different patterns of contrast agent leakage. This difference may be helpful in the diagnosis and preoperative differentiation between PCNSLs and high-grade gliomas, which sometimes may have similar conventional MR imaging appearance.
原发性中枢神经系统淋巴瘤（PCNSL）与其他肿瘤的术前鉴别对于术前分期、术中管理及术后治疗至关重要。动态磁敏感对比增强灌注磁共振成像（DSC灌注MRI）能够对颅内肿块病变的微血管系统进行活体评估。
确定DSC灌注MRI在鉴别PCNSL与高级别胶质瘤中的应用价值，以及它们在病理和生理方面的差异。
使用1.5T MRI扫描仪对9例经病理证实的PCNSL患者和11例高级别胶质瘤患者进行检查。通过梯度回波平面回波成像（GE-EPI）进行DSC灌注MRI检查。获取最大相对脑血容量（rCBV）比值、信号强度-时间曲线及信号强度恢复百分比。采用Student t检验比较PCNSL与高级别胶质瘤的最大rCBV比值及信号强度恢复百分比。使用抗CD34对手术标本进行免疫组织化学染色评估微血管密度（MVD），采用Student t检验比较两组肿瘤的MVD。
原发性颅内淋巴瘤的最大rCBV比值为1.72±0.59，而高级别胶质瘤为4.86±2.18。与高级别胶质瘤相比，PCNSL的灌注相对较低（P = 0.001），PCNSL抗CD34标记的MVD远低于胶质瘤（P < 0.001）。原发性颅内淋巴瘤的信号强度-时间曲线与高级别胶质瘤不同。与高级别胶质瘤相比，PCNSL的信号强度恢复百分比显著更高（P < 0.001）。
PCNSL与高级别胶质瘤在DSC灌注MRI特征上的差异由其不同的血管分布及造影剂渗漏模式决定。这种差异可能有助于PCNSL与高级别胶质瘤的诊断及术前鉴别，这两种肿瘤有时在传统MR成像表现上可能相似。
