Diagnostic Value Of Multimodal Imaging For Blood Flow Characteristics Of Pleomorphic Adenoma And Adenolymphoma Of Parotid Gland

Objective:To investigate the differential diagnosis value of blood flow characterstics of pleomorphic adenoma and adenolymphoma of parotid gland by multi-modal imaging which is the combination of SWI and CDFI,in order to improve the diagnostic rate of both,and to provide more reliable basis for the choice of clinical treatment.Methods:Analysis of patients with parotid gland tumors admitted to the China-Japan Union Hospital of Jilin University from January 2017 to December 2018.Among them,45 cases were pleomorphic adenoma and29 cases were adenolymphoma.All cases were confirmed by surgical pathology.Ultrasound and MRI were checked in our hospital before operation.Investigating the intravenous distribution,dv-max,the number of intratumoral veins per unit area(N/Svein)and the classification of ITSS in SWI sequence.Ultrasonography recorded the location,number,size,shape,boundary and internal echo of the tumors.Then CDFI was used to observe the blood flow in and around the lesions,especially the intravenous distribution.Then measuring dv-max,judging the graduation of blood flow,recording peak systolic velocity(PSV)and resistance index(RI).CDFI and SWI imaging were diagnosed separately.SPSS16.0software package was used to analyze the differences of the parameters of CDFI and SWI.The blood flow characteristics of pleomorphic adenoma and adenolymphoma were displayed and compared by CDFI,SWI,thecombination of SWI and CDFI.Further screening out the independent predictors of multimodal imaging in differential diagnosis between them.The diagnostic efficacy of each independent predictors was compard with the analysis of the AUC.Results:(1)A single factor analysis of the SWI signs of pleomorphic adenoma and adenolymphoma: There were statistical differences in the intravenous distribution,the graduation of ITSS,N/Svein and dvmax(P=0.000).The best critical values of dv-max 、 N/Svein and the graduation of ITSS were 1.535 、 2.91 、 1.5.Taking the maximum Youden index as the criterion,AUC values are 0.851、0.857 及 0.796.The sensitivity of intravenous distribution,the graduation of ITSS,N/Svein and dv-max in the diagnosis of pleomorphic adenoma and adenolymphoma are 84.0%、82.2%、85.7%、71.4%,the specificity are81.3%、72.4%、85.7%、89.3%.(2)A single factor analysis of the CDFI signs of pleomorphic adenoma and adenolymphoma: There were statistical differences in the intravenous distribution,the graduation of blood flow(P<0.05).However,there were no statistical differences in the PSV or RI.Taking the maximum Youden index as the criterion,the graduation of blood flow in the diagnosis of pleomorphic adenoma and adenolymphoma under the curve,sensitivity and specificity are 0.680,80.0%,51.7%.(3)The pleomorphic adenoma vein of the paroid gland was mainly distributed in the peripheral distribution,and the adenolymphoma vein was mainly distributed in the central distribution.Compared with CDFI,SWI can show the distribution of veins,drainage veins and microvessels in the lesion better,andwas particularly sensitive to vessels with slow flow rate and small diameter.(4)Comparing thediagnosis of pleomorphic adenoma and adenolymphoma by SWI or CDFI alone with that by CDFI combined with SWI,there was statistical difference between the methods(P < 0.05).The diagnostic efficiency of CDFI combined with SWI was more effective than that of the two methods alone,which could improve the preoperative diagnostic rate and has important clinical application value.Conclusion:SWI and CDFI have their own advantages in differentiating the blood flow characteristics of pleomorphic adenoma and adenolymphoma.The combination of SWI and CDFI can improve the differential diagnosis rate,and has important value for the choice of clinical operation and prognosis of tumors.