DCE-MRI鉴别单发IDH1野生型胶质母细胞瘤、原发性中枢神经系统淋巴瘤及转移瘤的临床价值

目的应用DCE-MRI评估单发IDH1野生型胶质母细胞瘤、PCNSL及转移瘤的微血管通透性,进一步探讨DCE-MRI鉴别这三种肿瘤的临床价值。方法收集80例病理确诊的脑肿瘤患者,其中IDH1野生型胶质母细胞瘤46例、PCNSL 16例、单发转移瘤18例。所有患者在术前进行DCE-MRI检查,获得Ktrans、Ve的最大值,并对其进行统计分析。P<0.05为差异有统计学意义。结果PCNSL的Ktrans、Ve值高于IDH1野生型胶质母细胞瘤及单发转移瘤,差异有统计学意义。当Ktrans=0.14 minKtrans(-1)、Ve=0.33时,鉴别PCNSL与IDH1野生型胶质母细胞瘤的灵敏度分别为80.4%、71.7%,特异度分别为93.8%、75.0%。当Ktrans=0.10 min^-1、Ve=0.20时,鉴别PCNSL与单发转移瘤的灵敏度分别为77.8%、72.2%,特异度分别为100%、93.8%。结论DCE-MRI可以定量评估IDH1野生型胶质母细胞瘤、PCNSL及单发转移瘤的微血管通透性,并可以无创性鉴别PCNSL与IDH1野生型胶质母细胞瘤或单发转移瘤。

磁共振波谱对早产儿缺血缺氧性脑病的诊断价值

目的:探讨氢质子磁共振波谱(proton magnetic resonance spectroscopy,~1 H-MRS)定量分析早产儿缺血缺氧性脑病(hypoxic ischemic encephalopathy,HIE)脑损伤的临床价值。方法:收集HIE早产儿28例,同时收集45例同胎龄段、同出生体质量的颅脑正常早产儿作为对照组。采用GE Signa 1.5T MR扫描仪进行~1 H-MRS扫描,通过GE工作站Functool软件计算得到~1 H-MRS图,测量右侧基底节区的乙酰天门冬氨酸/肌酸(NAA/Cr)、NAA/胆碱(NAA/Cho)、乳酸/Cr(Lac/Cr)比值。采用独立样本t检验分析HIE患儿与对照组右侧基底节区~1 H-MRS中各代谢物比值的差异。运用受试者工作特征(receiver operating characteristic,ROC)曲线分析~1 H-MRS中各代谢物比值鉴别HIE患儿的最佳阈值、灵敏度及特异度。结果:HIE患儿中,右侧基底节区NAA/Cho、NAA/Cr明显低于对照组(P<0.05);右侧基底节区Lac/Cr高于对照组(P<0.01)。右侧基底节区NAA/Cho与NAA/Cr为0.57、1.07时,鉴别HIE患儿与对照组新生儿的灵敏度分别为63.2%、89.5%、特异度分别为81.5%、55.6%;右侧基底节区Lac/Cr为0.09时,鉴别HIE患儿与对照组新生儿的灵敏度为89.5%、特异度为88.9%。结论:右侧基底节区的NAA/Cho、NAA/Cr、Lac/Cr有助于诊断早产儿HIE,为临床诊断早产儿HIE提供重要参考。

Microvascular permeability of brain astrocytoma with contrast- enhanced magnetic resonance imaging： correlation analysis with histopathologic grade

Background The degree of pathological microvascular proliferation is an important element in evaluation of the astrocytoma grade. This study was aimed to quantitatively assess the microvascular permeability of brain astrocytoma with the volume transfer constant （Ktrans） and volume of extravascular extracellular space per unit volume of tissue （Ve） from dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI） and to evaluate the effectiveness of the Ktr^n＇ and Ve in the grading of astrocytoma. Methods The highest values of the Kt~~s and Ve of 67 patients with astrocytoma （27 with grade II, 12 with grade III, and 28 with grade IV） were obtained. The comparisons of the differences of the Ktrans and Ve between the different grades were conducted using the Mann-Whitney rank-sum tests. Spearman＇s rank correlation coefficients were determined between Ktrans values, Ve values and astrocytoma grades. Receiver operating characteristic （ROC） curve analyses were performed to determine the cut-off values for the Ktrans and Ve to distinguish between the different grades of astrocytoma. Results There were significant differences （P〈0.001） between the different grades in the Ktrans values and Ve values, except for grades III and IV. The Ktrans values and Ve values were both correlated with astrocytoma grades （both P〈0.001）. The ROC curve analyses showed that the cut-off values for the Ktrans and Ve provided the best combination of sensitivity and specificity in distinguishing between grade II and grade III or IV astrocytomas. Conclusions DCE-MRI can play an important role in assessing the microvascular permeability and the grading of brain astrocytoma.