背景:为了研究从单指数得出的参数的诊断性能,双指数,和拉伸指数扩散加权成像模型可区分胶质母细胞瘤患者的肿瘤进展和假性进展。
方法:40例经病理证实的胶质母细胞瘤在完成放化疗后表现出增强性病变的患者被纳入研究。然后分为肿瘤进展和假性进展。所有患者均接受常规和多b扩散加权MRI检查。单指数模型的表观扩散系数(ADC),真实扩散系数(D),双指数模型的伪扩散系数(D*)和灌注分数(f),比较了肿瘤进展组和假性进展组之间的分布扩散系数(DDC)和拉伸指数模型的体素内异质性指数(α)。使用接收器工作特征曲线(ROC)分析来研究不同DWI参数的诊断性能。使用类间相关系数(ICC)来评估测量的一致性。
结果:ADC的值,D,DDC,肿瘤进展患者的α值低于假性进展患者(p<0.05)。肿瘤进展患者的D*和f值高于假性进展患者(p<0.05)。区分肿瘤进展与假性进展的诊断准确性α(AUC=0.94)比ADC(AUC=0.91)最高,D(AUC=0.92),D*(AUC=0.81),f(AUC=0.75),和DDC(AUC=0.88)。
结论:Multi-bDWI是一种具有较高诊断准确性的鉴别肿瘤进展和假性进展的有前景的方法。此外,从拉伸指数模型得出的α是预测胶质母细胞瘤患者肿瘤进展的最有前途的DWI参数。
To investigate the diagnostic performance of parameters derived from monoexponential, biexponential, and stretched-exponential diffusion-weighted imaging models in differentiating tumour progression from pseudoprogression in glioblastoma patients.
Forty patients with pathologically confirmed glioblastoma exhibiting enhancing lesions after completion of chemoradiation therapy were enrolled in the
study, which were then classified as tumour progression and pseudoprogression. All patients underwent conventional and multi-b diffusion-weighted MRI. The apparent diffusion coefficient (ADC) from a monoexponential model, the true diffusion coefficient (D), pseudodiffusion coefficient (D*) and perfusion fraction (f) from a biexponential model, and the distributed diffusion coefficient (DDC) and intravoxel heterogeneity index (α) from a stretched-exponential model were compared between tumour progression and pseudoprogression groups. Receiver operating characteristic curves (ROC) analysis was used to investigate the diagnostic performance of different DWI parameters. Interclass correlation coefficient (ICC) was used to evaluate the consistency of measurements.
The values of ADC, D, DDC, and α values were lower in tumour progression patients than that in pseudoprogression patients (p < 0.05). The values of D* and f were higher in tumour progression patients than that in pseudoprogression patients (p < 0.05). Diagnostic accuracy for differentiating tumour progression from pseudoprogression was highest for α(AUC = 0.94) than that for ADC (AUC = 0.91), D (AUC = 0.92), D* (AUC = 0.81), f (AUC = 0.75), and DDC (AUC = 0.88).
Multi-b DWI is a promising method for differentiating tumour progression from pseudoprogression with high diagnostic accuracy. In addition, the α derived from stretched-exponential model is the most promising DWI parameter for the prediction of tumour progression in glioblastoma patients.