Application of CT-MRI homoposition fusion images in delineation of high-grade Glioma radiotherapy target
Objective To explore the clinical application value of MRI imaging(MRIsim)and CT simulated localization posi-tioning image fusion in delineation of radiotherapy target area of high-grade glioma.Methods A total of 20 glioma patients performed postoperative radiotherapy were enrolled,which included 13 males and 7 females,aged 39-69 years old with mean age of 45.5.All of the patients were single lesions,and underwent total or incomplete resection,which confirmed by pathological diagnosis.According to World Health Organization(WHO)classification,there were 6 cases of grade Ⅲ and 14 of grade Ⅳ.The MRIsim and conventional MRI images(MRIconv)with simulated localization CT image of each patient were fused,Dice similarity index(DSC)and Hausdorff distance(HD)algorithm were used to evaluate the accuracy of registration.The organs at risk(OAR)and target areas[gross tumor target(GTV)and clinical tumor target(CTV)]were delineated on CT and MRIsim fusion images(Fusion-CT MRIsim)and CT and MRIconv fusion images(Fusion-CT MRIconv),respectively.The OAR delineation volume,GTV,CTV and dosimetric differences between the two fusion images(Fusion-CT MRIsim group and Fu-sion-CT MRIconv group)were evaluated.Results The fusion accuracy evaluation:Except for the whole brain,the OAR DSC of Fusion-CT MRIsim group was higher than that of Fusion-CT MRIconv group(P＜0.05),while the OAR HD of Fusion-CT MRIsim group was smaller than that of Fusion-CT MRIconv group(P＜0.05).There was no significant difference in volume of OAR delineation between Fusion-CT MRIsim group and Fusion-CT MRIconv group(P＞0.05).Target volume:GTV and CTV in Fusion-CT MRIsim group were smaller than those in Fusion-CT MRIconv group[(118.2±8.0)cm3 vs(125.3±8.1)cm3,(234.3±12.8)cm3 vs(256.0±13.4)cm3],and the differences were statistically significant(P=0.000).There was no significant difference in maximum dose(Dmax)-PTV,mean dose(Dmean)-PTV between Fusion-CT MRIsim group and Fusion-CT MRIconv group[(6 432.9±23.0)cGy vs(6 430.4±25.2)cGy,(6 159.0±13.7)cGy vs(6 166.2±17.3)cGy](P＞0.05).Conclusion It is demonstrated that CT-MRIsim showed high registration accuracy,which could reduce whole brainDmeanand reduce GTV and CTV,and is a worthy clinical method for accurate radiotherapy after high-grade brain glioma.
NETL
NSTL
万方数据
维普
