The Multimodal Imaging Technique Based On Magnetic Resonance Distinguishes The Recurrence Of Glioma And The Response After Treatment

Part one: Comparative study of three dimensional pseudo-continuous arterial spin labeling and dynamic susceptibility contrast perfusion imaging in the differentiation between tumor recurrence and treatment effects in glioma Purpose: To compare three dimensional pseudo-continuous arterial spin labeling(3D-pcASL)technique and dynamic susceptibility contrast perfusion magnetic resonance imaging(DSC-MRI)for differentiation tumor recurrence from radiation treatment effects in gliomas.Materials and Methods: Twenty-nine patients with gliomas previously who showed new or enlarged,contrast-enhancing lesions within the radiation field after surgery and concurrent chemoradiotherapy(CCRT)underwent conventional MR scan(unenhanced and enhanced scans),and perfusion MR scan(3D-pcASL and DSC-MRI).These patients were classified into two groups,tumor recurrence group(n=17)and treatment effects group(n=12),based on pathologic analysis or clinical-radiologic follow-up.The perfusion imaging quality was assessed was assessed using a 3-point scale(1= poor imaging with extensive(maximum diameter>2 cm)susceptibility artefacts,2 = moderate imaging with small(maximum diameter<2 cm)susceptibility artefacts and 3 = good imaging without susceptibility artefacts).Comparison for susceptibility-artifact score between the two techniques was performed with Wilcoxon one-sample test.Regions of interest(ROIs)of the enhanced lesions were manually drawn within the abnormal enhancement areas and were copied to the contralateral regions.Relative cerebral blood flow(rCBF)values and relative cerebral blood volume(rCBV)values were then calculated by dividing the value of enhanced lesion ROI by the value of the contralateral brain tissue on ASL-CBF(ASL-rCBF)map,DSC-CBF(DSC-rCBF)map and DSC-CBV(DSC-rCBV)map.Quantitative analyses were performed between tumor recurrence group and treatment effects group with cerebral blood flow values(ASL-CBF),relative cerebral blood flow values(ASL-rCBF,DSC-rCBF)and relative cerebral blood volume values(DSC-rCBV)using Wilcoxon one-sample test.Results: The imaging-quality score of 3D-pcASL was higher than that of DSC-MRI(p=0.01).The perfusion parameters(including ASL-CBF,ASL-rCBF,DSC-rCBF and DSC-rCBV)of tumor recurrence group were higher than those of treatment effects group,and the differences between them had statistically significant differences.There was a significant correlation between ASL-rCBF and DSC-rCBF values(r=0.803),as well as ASL-rCBF and DSC-rCBV values(r=0.763).Using a cutoff value of 1.110,ASL-rCBF showed larger AUC than other parameters,however,there were no significant differences among different AUCs.Conclusions: 3D-pcASL is an alternative perfusion method to DSC-MRI for the differentiation between tumor recurrence and radiation treatment effects in gliomas.3D-pcASL is noninvasive and shows fewer susceptibility artifacts than DSC-MRI.Part two: Differentiation glioma recurrence from treatment-related effects by multi-b-value diffusion-weighted imaging Purpose: To evaluate the role of multi-b-value diffusion-weighted imaging(DWI)in the differentiation of tumor recurrence from radiation treatment effects in gliomas.Materials and Methods: Tirty-one patients with gliomas previously who showed new or enlarged,contrast-enhancing lesions within the radiation field after surgery and concurrent chemoradiotherapy(CCRT)underwent conventional MR scan(unenhanced and enhanced scans),and multi-b-value DWI MR scan(e DWI).These patients were classified into two groups,tumor recurrence group(n=16)and treatment effects group(n=15),based on pathologic analysis or clinical-radiologic follow-up.Regions of interest(ROIs)of the enhanced lesions were manually drawn within the abnormal enhancement areas and were copied to the contralateral regions.e DWI derived parameters were processed by fitting the bi-exponential model(Slow ADC_Mono,Fast ADC_Mono and Fraction of Fast ADC_Mono)and the tensile index model(DDC and Alpha).Relative values were then calculated by dividing the values of enhanced lesion ROI by the values of the contralateral brain tissue on Standard ADC map,Slow ADC map,Fast ADC map,Fraction of Fast ADC map,DDC map and Alpha map.Quantitative analyses were performed between tumor recurrence group and treatment effects group with the values of e DWI-derived parameters using Independent-Samples T test or Mann-Whitney test.Correlation analyses of the parameters of e DWI were also carried out.Results: e DWI perfusion-related parameters(including Fast ADC,Fraction of Fast ADC and their relative values)of tumor recurrence group were higher than those of treatment effects group,and the other parameters of e DWI(including Standard ADC,Slow ADC,DDC,Alpha and their relative values)of tumor recurrence group were lower than those of treatment effects group.The differences between them had statistically significant differences.There was a significant correlation between Standard ADC and Slow ADC values(r=0.972),as well as Standard ADC and DDC values(r=0.805).AUCs of Fast ADC,Fraction of Fast ADC and their relative values were higher than 0.6,while those of Standard ADC,Slow ADC,DDC,Alpha and their relative values were lower than 0.5.Conclusions: Multi-b-value DWI could be used to identify glioma recurrence and treatment effects.e DWI perfusion-related parameters are important biomarker for differentiating tumor recurrence from treatment effects in gliomas.Part three: Differentiation glioma recurrence from treatment-related effects by texture analysis of magnetic resonance imaging Purpose: To explore the role of texture analysis with MR enhanced images in the differentiation of tumor recurrence from treatment effects in gliomas.Materials and Methods: Forty-three patients with gliomas previously who showed new or enlarged,contrast-enhancing lesions within the radiation field after surgery and concurrent chemoradiotherapy(CCRT)underwent unenhanced and enhanced MR scans.These patients were classified into two groups,tumor recurrence group(n=23)and treatment effects group(n=20),based on pathologic analysis or clinical-radiologic follow-up.Two senior radiologists used the blind method to apply the texture analysis software on MR enhanced images to draw the boundary of the intracranial abnormal enhanced lesions and measure the quantitative parameters of texture analysis in the lesions.The intra-class correlation coefficient(ICC)was used to evaluate the consistency of measurements.Quantitative analyses were performed between tumor recurrence group and treatment effects group with the values of texture analysis-derived parameters using Independent-Samples T test or Mann-Whitney test.Receiver operating characteristics(ROC)was also performed to assess sensitivity and specificity for the differentiation between the two groups.Results: ICCs of Energy,Entropy,Inertia,Cluster Shade,Short Run Emphasis,Long Run Emphasis,Low Grey Level Run Emphasis,High Grey Level Run Emphasis,Short Run Low Grey Level Emphasis and Long Run Low Grey Level Emphasis were poor or fair,and ICCs of the other parameters were good or excellent.Texture analysis parameters(including Volume Count,Voxel Value Sum,Relative Deviation,Skewness,Kurtosis,Grey Level Nonuniformity and Run Length Nonuniformity)of tumor recurrence group and treatment effects group had statistically significant differences.AUCs of Volume Count,Voxel Value Sum,Grey Level Nonuniformity and Run Length Nonuniformity were higher than 0.6,while those of Relative Deviation,Skewness and Kurtosis were lower than 0.5.Conclusions: Texture analysis with MR enhanced images could be used to identify glioma recurrence and treatment effects.