论文部分内容阅读
目的：对比不同灌注模式下，各定量参数对脑膜瘤的诊断效能。方法23例经手术病理确诊的脑膜瘤，术前行MRI常规扫描和灌注检查。灌注检查包括：动态弛豫对比增强（DCE）和动脉自旋标记（ASL）两种模式，分别在瘤体实质区和对侧镜像脑区勾画感兴趣区（ROI），测量DCE-MRI定量参数：容积转运常数（Ktrans）、返流常数（Kep）、血管外细胞外间隙容积分数（Ve）、血浆容量（Vp）、血容量（BV）、血流量（BF）、平均通过时间（MTT）和达峰时间（TTP）；ASL-MRI定量参数：脑血容量（ CBF）。配对t检验观察瘤体实质区和镜像脑区上述参数差异性，受试者工作特征（ ROC）曲线评估各参数对脑膜瘤的诊断效能。结果配对t检验显示瘤区与对侧脑区灌注参数存在统计学差异，Ktrans：（0．329±0．207） min-1 vs．（0．003±0．003）min-1（ P ＜0．001；Kep：（0．880±0．480）min-1 vs．（0．259±0．246）min-1（ P ＜0．001；Ve：（0.421±0．294） vs．（0．060±0．071）（ P ＜0．001；Vp：（0．164±0．186） vs．（0．027±0．022）（ P ＝0．001）；BV：（53.551±27.499）ml／100g vs．（5．279±3．870）ml／100g（ P ＜0．001；BF：（139．405±70．771） ml／100g．min vs．（22．336±21．099） ml／100g．min（ P ＜0．001；MTT：（0．395±0．110）s vs．（0．247±0．091）s（ P ＜0．001；TTP：（2．510±0．754）s vs．（1．381±0.506）s （ P ＜0．001；CBF：（85．300±51．786）ml／100g．min vs．（42．018±17．635）ml／100g．min（ P ＝0.001）。定量参数中，诊断效能最高的参数为Ktrans和BV（DCE-MRI），当截断点（cut-off point）选取0．164min-1、16.518ml／100g，诊断脑膜瘤的特异性和敏感性均为100％；诊断效能最低的参数为CBF（ASL-MRI），当cut-off point选取60．949ml／100g．min，诊断脑膜瘤特异性为82．6％，敏感性为73．9％。结论 DCE-MRI得到的参数多、诊断效能高，Ktrans、Kep、Ve和Vp的测量丰富了灌注信息，并能从血管通透性的角度对结果进行分析；无需注入外源性对比剂是ASL-MRI最大优点，且CBF也有助于脑膜瘤的诊断，但参数单一和干扰因素大。“,”Objective The diagnostic efficiency of different quantitative parameters in meningioma was compared between dy -namic contrast enhancement (DCE) and arterial spin labeling (ASL).Method s Twenty three cases of meningioma diagnosed by surgery and pathology were accepted MRI conventional scan and perfusion examination including DCE -MRI and ASL-MRI be-fore operation.The quantitative parameters were measured in the region of the tumor and the contralateral brain region .The differ-ence of the perfusion parameters in the tumor area and the contralateral area were counted by paired t test.The diagnostic efficacy of each parameter in the meningioma was evaluated using receiver operating characteristic (ROC) curves.Results The perfusion parameters was significant difference between the tumor area and the contralateral cerebral according paired t test , such as Ktrans:(0.329 ±0.207) min-1 vs.(0.003 ±0.003) min-1( P <0.001, Kep:(0.880 ±0.480) min-1 vs.(0.259 ±0.246) min-1( P<0.001, Ve:(0.421 ±0.294) vs.(0.060 ±0.071) ( P <0.001, Vp: (0.164 ±0.186) vs.(0.027 ±0.022) ( P =0.001), BV:(53.551 ±27.499) ml/100g vs.(5.279 ±3.870) ml/100g ( P <0.001, BF:(139.405 ±70.771) ml/100g. min vs.(22.336 ±21.099) ml/100g.min ( P <0.001, MTT:(0.395 ±0.110) s vs.(0.247 ±0.091) s ( P <0.001, TTP:(2.510 ±0.754) s vs.(1.381 ±0.506) s ( P <0.001, CBF:(85.300 ±51.786) ml/100g.min vs.(42.018 ±17.635) ml/100g.min ( P =0.001).The highest diagnostic efficiency parameters were Ktrans and BV .The cut-off point of the Ktrans was found to be 0.1640 min-1.This value provided the best trade-off between sensitivity (100%) and specificity (100%).The best cut-off point of BV was 16.518 ml/100g.At this level, sensitivity was 100% and specificity was 100%.The lowest diagnostic parameter was CBF (ASL-MRI).When cut-off point was 60.949 ml/100g.min, the specificity was 82.6% and the sensitivity was 73.9%.Conclusion More parameters and higher diagnostic efficiency can be got with DCE-MRI.The greatest advantage of ASL-MRI was without exogenous contrast agent .CBF can also be helpful to the diagnosis of meningioma , but the parameters of ASL-MRI was single and with much disturbed factors .