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Objective:MR-PWI and MR-DWI were supplementary functional methods to differentiate benign from malignant bone tumors.The aim of this study was to assess the diagnostic potential of MR-PWI conjunction with MR-DWI in differentiating benign from malignant bone tumors.Methods:MR-PWI and MR-DWI were performed on 39 patients by using a 1.5 T MR imager.Perfusion imaging was started with GRE-EPI sequence as soon as che bolus administration commenced.With b value as 300 s/mm2,diffusion imaging was performed with SE-EPI sequence.mype of TIC,peak enhancement,steepest slope,signal difference between 2 baselines and ADC were compared between benign and malignant bone tumors.The data were analyzed with soft-ware(SPSS,version 13.0).Subjective overall pefrormance of two techniques was evaluated with Receiver Operating Characteristic(ROC)analysis.Resuits:1.MR-PWI:(1)The Pattes of TIC of most benign bone tumors(17/21)were type Ⅰ and Ⅱ,and all malignant bone tumors were type Ⅲ and Ⅳ.(2)There were significant differences in peak enhancemenl(17.52±2.37 vs.52.42±5.74)%,steepest slope(4.69±2.84 vs.9.63±4.05)%/S and signal difference between 2 baselines(6.87±3.34 vs.31.75±11.0g)% between benign and malignant groups.And their diagnosis accuracy was 82.1%,79.5% and 87.2%,respectively.(3).4 highly vascularized benign bone tumors were mistaken in diagnosis as malignant ones according to their perfusion characteristics.2.MR-DWI:There was significant difference between ADC of benign and malignant groups[(1.86±0.38)vs.(1.44±0.26)] ×10-3 mm2/s when b value was 300 s/mm2.The diagnosis accuracy was 79.5% when ADC value less than 1.63×10-3 mm2/s was considered as malignant ones.3.The diagnosis accuracy of MR-PWI and MR-DWI were 89.7% and 79.5%.respectively.Conclusion:MR-PWI is lhe better valuable technique than MR-DWI in differentiation benign from malignant bone tumors.To suspicious highly vascularized bone tumors.MR-PWI combining with MR-DWI lead to higher diagnosis accuracy.