Value of MR three dimensional arterial spin labeling perfusion imaging and intravoxel incoherent motion diffusion weighted imaging in differential diagnosis of musculoskeletal tumors / 中华放射学杂志

ABSTRACT

Objective To evaluate the value of MR threedimensional arterial spin labeling (3D-ASL) perfusion imaging and intravoxel incoherent motion(IVIM) DWI in differential diagnosis and quantitative analysis of musculoskeletal tumors.Methods Forty-four patients with musculoskeletal tumors were included.According to pathologic results,there were 12 cases of benign tumors,10cases of intermediate tumors and 22 cases of malignant tumors.3D-ASL and IVIM DWI were both performed on forty-four patients to gain tumor blood flow (TBF),standard ADC (ADCstandard),slow ADC (ADCslow)and fast ADC (ADCfast).Immunohistochemical staining of specimens was performed by using CD34 monoclonal antibody to calculate microvessel density (MVD) counts.MVD,TBF,ADCfast and ADCslow of different groups were compared by one-way ANOVA analysis.ADCstandard was compared by Kruskal-Wallis test.ROC curve was used to analyze ASL and IVIM DWI,in order to determine the threshold and diagnostic reliability.Results The MVD of benign tumors was 10±4,the MVD of intermediate tumors was 15±6,and malignant tumors was 33 ± 1 1.There was significant difference among three groups of MVD(F=28.33,P＜0.05).There was better intra-observer agreement for ADCstandard,ADCfast,ADCslow and TBF(ICC=0.970,0.885,0.778,0.891,respectively,P＜0.05).The TBF of benign tumors was(30±10)ml· min-1· 100 g-1,intermediate tumors was(30± 12) ml·min 1· 100 g-1,and malignant tumors was(84±29)ml·min 1· 100 g-1.There was significant difference among three groups of TBF(F=32.34,P＜0.05).According to the ROC analysis,when the cut-offvalue of TBF was 45.5 ml·min-1· 100 g-1,the area under ROC curve was 0.95 1,and the sensitivity and specificity of TBF in diagnosing malignant tumors were 90.9％ and 95.5％ respectively.There was no significant difference among three groups of ADCstandard,ADCfastand ADCslow of benign tumors were(9.9±5.1)× 10-3,(1.9±0.5) × 10-3mm2/s respectively.ADCfast and ADCalow of intermediate tumors were(8.2 ± 3.6) × 10-3,(1.5 ± 0.6) × 10-3mm2/s respectively.ADCfast and ADCalow of malignant tumors were (16.9 ± 5.8) × 10 3,(1.4 ± 0.6) × 10-3mm2/s respectively.There were significant difference of ADCfast and ADCslow among three groups (F=12.75,5.60,P＜ 0.05).According to the ROC analysis,when the cut-off value of ADCfast was 9.4× 10-3mm2/s,the area under ROC curve was 0.861,the sensitivity and specificity of them in diagnosing malignant tumors were 95.5％ and 68.2％ respectively.Conclusion 3D-ASL and IVIM DWI are valuable in the differential diagnosis of musculoskeletal tumors.