The Application Of Susceptibility Weighted Imaging And Diffusion Weighted Imaging In Differential Diagnosis Of Benign And Malignant Tumors Of Extremities

Objective:1、we investigate the clinical application of Susceptibility Weighted Imaging and Diffusion weighted imaging in Differential Diagnosis of benign and malignant tumors of extremities.2、we analyze the T2*-Mapping, R2*-Mapping、phase imaging and magnitude imaging in SWI,and explore the internal relationship between the four ones.Materials and Methods:A total of64patients(38male,26female) with the extremity tumors comfirmed by pathology after surgery were evaluated..Among these64patients who age1-84years(mean31.5years),24ones have a bone tumor,40ones have a soft tissue tumor,and39of them with carcinods include18angiomas,4desmoid tumors,4fibromas,2neurofibromas,2osteofibrous dysplasia,1giant cell tumor of tendon sheath,1myxoma,5lipomas,2limphangiomas and25of them with malignancies include5osteosarcomas,2Ewing tumors,2malignant fibrous histiocytomas(MFH),1adamantinoma,1bone hemangiosarcoma,1chordoma,1osteoblastoma,1bone metastasis,1malignant giant-cell tumor of bone,1osteochondrosarcoma,9soft-tissue sarcomas. All patients underwent a routine preoperative MR examination including T1-and T2-weighted sequence,susceptibility-weighted sequence, diffusion-weighted sequence and enhanced T1WI.Phase values,T2*-values,R2*-values and magnitude all were measured in GE ADW4.3.Phase imaging,magnitude imaging multiplied phase mask,T2*-mapping and R2*-mapping were established by SWI-functool protocol and ADC-mapping,EDC-mapping by DWI-functool protocol. Phase values(PS,Radian as unit),T2*-values(ms as unit),R2*-values(HZ as unit) and magnitude(M) of the hypointense regions(where the hypointense regions in magnitude imaging) and the active regions(where the most apparent in the early post-contrast) were respectively measured and so also is ADC values(mm/s2as unit) and EDC values within and a radius of1cm from the tumor lesions. Statistical analysis:all measured values was expressed as mean±SD.Indepedent-samples t-test were used between benign and malignant and Paired-samples t-test between the hypointense regions and the active regions.All of four contrasts(including CONTRASTPS,CONTRASTWT2,CONTRASTWR2,CONTRASTM) were compaed with each other using K-Related Sample Test.Correlations were analyzed with spearman test and all of quantitative interdependence comparisons were described with Curve Estemation,which is one of Regression analysises.Finally,The differential threshold of benign and malignant for all measured values were acquired using ROC Curve,and the optimal differential method were also obtained. Statistical calculations were performed using spss13.0version with a significance level of0.05.Result:1、Excluded WR2H,MH,MA,MeanWR2,the other12ones of all15measured values were considered statistically significant(P<0.05).The hypointense regions and the active regions of phase values,T2*,R2*,magnitude have significant difference,as well as four contrasts.The MeanPS is the most valuable way of differential diagnosis draw from ROC Curve,and0.88,0.846,0.922,-0.0188Radians is the sensitivity,specificity,area under curve(AUC),threshold,respectively.And0.88,0.744,0.885,-0.09553Radians is also the sensitivity,specificity,area under curve(AUC),threshold,respectively for the following PSH.The results of correlation:Negative linear correlation is found between PSH and WT2H(P<0.01),and is not found in PSH-WR2HPSH-MH(P>0.05).Moreover,CONTRASTPS and CONTRASTWT2,CONTRASTWT2and CONTRASTWR2,CONTRASTPS and CONTRASTM shows negative linear correlation(P<0.01),and positive correlation for CONTRASTWT2-CONTRASTM,CONTRASTWR2-CONTRASTM(P<0.01). The last, CONTRASTPS and MeanWT2, CONTRASTWR2and CONTRASTWT2shows negative linear correlation(P<0.01),and growth with MeanWT2,CONTRASTWT2is expected(P<0.01).But it has no linear correlation between CONTRASTM and MeanWT2.2、intratumoral ADC(INADC) and peritumoralADC(PEADC) have Significant differences between benign and malignant. The INADC is the better valuable way of two differential diagnosis draw from ROC Curve,and0.88,0.641,0.735,1.247×10-3Radians is the sensitivity,specificity,area under curve(AUC),threshold,respectively.Conclusions:1、Multiunit of measured values is obtained through the post-processing protocol.The quantative analysises for discrimination of benign and malignant were performed,as well as the quantitative comparative analysises for the optimal discrimination method and the threshold.2、By means of correlation and regression analysis,SWI sequnence characteristic is described.