Dosimetric comparison of different types of multileaf collimators in volumetric modulated arc therapy for cervical cancer
Objective To investigate the dosimetric differences of different types of multileaf collima-tors(MLCs)on the planning target volume(PTV)and organs at risk(OARs)in volumetric modulated arc therapy(VMAT)for cervical cancer.Methods Twenty postoperative patients with cervical cancer receiving radiotherapy in this hospital from May 2023 to January 2024 were selected as the study subjects.For each pa-tient,two kinds of VMAT plans(MLCi2-MLC and AgilityTM-MLC)after cervical cancer operation were de-signed.The dosimetric parameters of the planning target volume(PTV),exposure dose by organs at risk(OAR),y passing rate and monitor units(MU)were compared between the two plans.Results Compared with MLci2-MLC,prescription dose(V45),conformity index(CI)and homogeneity index(HI)in AgilityTM-MLC were better,and the differences were statistically significant(P＜0.05),Compared with MLCi2-MLC,bladder V30,V40,average dose(Dmean),rectal V10,V20,V30,left femoral head V10,Dmean and small intestine V10,V30,Dmean and Dmax were lower,bladder V45,rectal V45,right femoral head V20 were higher,and the differences were statistically significant(P＜0.05).Compared with MLCi2-MLC,the y passing rate in AgilityTM-MLC was lower[(98.31±0.64)％vs.(99.73±0.37)％],and the difference was statistically significant(P＜0.05);while MU had no statistical difference between AgilityTM-MLC and MLCi2-MLC(996.74±65.46 vs.996.80±49.77,P＞0.05).Conclusion AgilityTM-MLC demonstrates better PTV conformity and homogenei-ty,as well as good protection on OARs in both high and low dose regions.
cervical cancermultileaf collimatororgans at riskvolumetric modulated arc therapydo-simetry
万方数据
维普
