动态磁敏感对比增强MRI和动态对比增强MRI鉴别诊断胶质瘤复发和放射性脑损伤

目的 探讨动态磁敏感对比增强MRI（DSC-MRI）及动态对比增强MRI（DCE-MRI）在鉴别脑胶质瘤术后放化疗后复发和放射性脑损伤中的临床应用价值。方法 对19例经临床病理确诊为脑胶质瘤患者在术后、放化疗前、放化疗后定期行DSC及DCE检查，得到相关的血流动力学参数值并将灌注成像影像诊断结果与临床最终诊断结果对照，分析各灌注参数在鉴别诊断中的价值。结果 11例为胶质瘤复发，8例为放射性脑损伤。胶质瘤复发患者的rCBF、rCBV、K_trans、V_e及riAUC值均明显高于放射性脑损伤患者（P均<0.05）；而K_ep、V_p值在胶质瘤复发或放射性脑损伤患者差异无统计学意义（P=0.37、0.22）。K_trans联合rCBV共同诊断，并、串联试验中鉴别诊断的敏感度分别为90.9%、72.7%；特异度分别为62.5%、100%。结论 DCE及DSC均可鉴别肿瘤复发或放射性脑损伤。K_trans、riAUC及rCBV诊断效能略高于V_e及rCBF，联合应用rCBV及K_trans可提高诊断正确率。

DSC-MRI and DCE-MRI in differentiating recurrent tumour from radiation-induced brain injuries in patients with glioma

Objective To explore the clinical significance of dynamic susceptibility contrast (DSC) perfusion MRI and dynamic contrast-enhanced (DCE) permeability MRI in distinguishing radiation-induced brain injuries from recurrence in glioma patients. Methods Nineteen pathologically diagnosed glioma patients were performed MR scanning with DSC and DCE after surgery, before and after synchronous chemoradiotherapy. Hemodynamic parameter value were got, and the perfusion imaging results and the final clinical diagnosis were contrasted. The differential diagnostic values of the perfusion parameters were analyzed statistically. Results Eleven cases were recurrent glioma, while 8 cases were radiation-related injuries. The values of recurrent pateints including relative cerebral blood volume (rCBV), relative cerebral blood flow (rCBF), volume transfer constant (K_trans),volume fraction of extravascular extracellular space (V_e) and initial area under the signal intensity-time curve (riAUC) were significantly higher than those of radiation-induced brain injuries patients (all P<0.05). While there were no significantly statistical differences of transfer constant from the extracellular extravascular space into the plasma (K_ep) and blood plasma volume (V_p) between glioma recurrence and radiation-induced injuries (P=0.37, 0.22). Combining the optimal parameters rCBV with K_trans in the differentiation diagnoses of the series and parallel tests, the sensitivity were 90.9%, 72.7%; while the specificity were 62.5%, 100% respectively. Conclusion Both DSC and DCE can distinguish glioma recurrence from radiation-induced brain injuries. The parameters K_trans, riAUC and rCBV values seems to be slightly efficient in diagnosis than rCBF and Ve, while combined with K_trans and rCBV, the diagnostic accuracy may be improved.