Objective:To assess the dosimetric performance of HyperArc and volumetric modulated arc radiotherapy(VMAT)techniques,using either full or ipsilateral arcs,for the radiotherapy of unilateral temporal lobe tumor,in orde...Objective:To assess the dosimetric performance of HyperArc and volumetric modulated arc radiotherapy(VMAT)techniques,using either full or ipsilateral arcs,for the radiotherapy of unilateral temporal lobe tumor,in order to quantify and analyze differences among these planning approaches using various dosimetric parameters.Methods:This retrospective study reviewed 30 patients with unilateral temporal lobe tumors treated with radiotherapy in the Department of Radiation Oncology,Shenzhen People's Hospital from August 2020 to December 2023.Using the Eclipse treatment plan system with the Truebeam machine model,HyperArc and VMAT plans were designed with full or ipsilateral arcs,respectively Dosimetric parameters for the planning target volume(PTV)and organs at risk(OARs)were computed and analyzed.Additionally,the monitor units(MU)of four types of plans were calculated for consideration of rays utilization and delivery efficiency.Results:HyperArc demonstrated superior dosimetric performance for PTV and OARs compared to VMAT(P<0.05),with exceptions noted for the low dose volume(V5 Gy)of the healthy brain and mean dose of ipsilateral cochlea.Ipsilateral arcs and full arcs showed similar efficacy in sparing OARs adjacent to PTV.Furthermore,full arcs improved PTV conformity compared with ipsilateral arcs(P<0.05),while ipsilateral arcs reduced the dose to contralateral OARs,mean dose and the middle-to-low dose volume of the healthy brain(P<0.05).Regarding MU,HyperArc(full)plans exhibited the minimum values among the four plan types,with overall MU for HyperArc plans being less than those for VMAT.Conclusions:This study not only highlights the outstanding performance of the HyperArc technique with respect to VMAT but also underscores the advantages of employing ipsilateral arcs over full arcs in the radiotherapy of unilateral temporal lobe tumor.Additionally,the HyperArc technique demonstrated higher efficiency of ray utilization and delivery.The findings of this study can aid in selecting appropriate techniques and guiding arcs arrangements for the radiotherapy of unilateral temporal lobe tumor.展开更多
Objective:To assess the performance and advantages of HyperArc for radiotherapy of multiple brain metastases with dosimetric parameters with respect to coplanar volumetric modulated arc radiotherapy(c-VMAT),and charac...Objective:To assess the performance and advantages of HyperArc for radiotherapy of multiple brain metastases with dosimetric parameters with respect to coplanar volumetric modulated arc radiotherapy(c-VMAT),and characterize implicit correlations between tumor features and dosimetric parameters.Methods:This retrospective study involved 40 patients with multiple brain metastases(4–16 tumors,12.8–240.8 cm3)who received simultaneous radiotherapy at the Department of Radiation Oncology,Shenzhen People's Hospital from January 2019 to December 2022.Both HyperArc and c-VMAT plans were designed by the same and qualified physicist using the Eclipse system with Truebeam.A single isocenter and a 6 MV flattening filter-free(6FFF)photon beam were used for radiotherapy of multiple brain metastases in each plan.Dosimetric parameters of tumors and organs at risk(OARs)were compared between HyperArc and c-VMAT plans.Corre-lations between tumor features(number and volume)and dosimetric parameters were revealed and analyzed.Furthermore,monitor units(MUs)of both plan types were recorded to assess rays utilization and delivery efficiency.Results:Compared to c-VMAT plans,HyperArc plans achieved higher maximum dose(D_(max))(5.23%,t=7.87,P<0.01),but lower minimum dose(Dmin)(3.94%,t=-2.12,P=0.04)and mean dose(D_(mean))(1.05%,t=-3.29,P<0.01)for planning gross tumor volumes(PGTVs).The conformity index(CI),homogeneity index(HI),gradient index(GI)and R50%of PGTVs with HyperArc were better than those with c-VMAT,with the improve-ments of 20.78%,1.68%,19.83%and 36.20%,respectively(P<0.01).The dosimetric parameters of OARs were significantly improved in HyperArc plans compared to c-VMAT plans.Specifically,the D_(max)and the D_(mean)to the brainstem decreased by 16.14%and 11.37%,respectively.The D_(max)for eye_L decreased by 16.88%,for eye_R decreased by 11.67%,for optical nerve_L decreased by 12.56%,and for chiasm decreased by 18.12%.Few correlations were observed between the differences of CI/HI/GI/R50%and the number of PGTVs between the two plan types.Whereas,regression analysis indicated that the differences of CI/GI/R50%were negatively correlated with the volume of PGTVs,respectively.Moreover,although HyperArc plans reduced the MUs by 4.74%compared to c-VMAT,no significant difference was observed(P>0.05).Conclusions:This study demonstrates the promising performance of HyperArc for radiotherapy of multiple brain metastases,including better dose conformity for the tumors,more rapid dose drop and less dose spillage outside the tumors area,effective reduction of dose bridges among close tumors,and sparing OARs.It also reveals the correlations between the number or volume of tumors and dose parameters,which can help optimize the use of HyperArc and predict clinical benefits.展开更多
[目的]分析不同放疗技术在多发性脑转移瘤立体定向放射治疗(stereotactic radiotherapy,SRT)中的剂量学差异。[方法]回顾性分析上海交通大学医学院附属瑞金医院2022年4月至9月多发性脑转移瘤10例病例,处方剂量35 Gy/5 f,分别采用容积弧...[目的]分析不同放疗技术在多发性脑转移瘤立体定向放射治疗(stereotactic radiotherapy,SRT)中的剂量学差异。[方法]回顾性分析上海交通大学医学院附属瑞金医院2022年4月至9月多发性脑转移瘤10例病例,处方剂量35 Gy/5 f,分别采用容积弧形调强放射治疗技术(volumetric modulated arc therapy,VMAT),单中心非共面弧形调强放射治疗技术(HyperArc,HA),螺旋断层放射治疗(helical tomotherapy,HT)技术生成4种计划:VMAT,HA,使用1.0 cm射野宽度的HT(helical tomotherapy,1.0 cm field width,HT-1.0)和使用2.5射野宽度的HT(helical tomotherapy,2.5cm field width,HT-2.5)计划,比较4种计划的靶区适形性指数(conformal index,CI)、均匀性指数(homogeneity index,HI)、剂量梯度跌落指数(gradient index,GI),以及危及器官(organ at risk,OAR)包括脑干、左右晶体、左右视神经的最大剂量D_(max),脑平均剂量D_(mean)以及脑剂量体积V_(5Gy),V_(8Gy),V_(10Gy),V_(12Gy),V_(15Gy),V_(20Gy),V_(25Gy),V_(30Gy),并统计出束时间。探究靶区体积和靶区间距对各技术间脑剂量学参数差异的影响。[结果]VMAT和HA计划的CI无统计学差异(0.928±0.015 vs 0.928±0.008,P=0.980),均高于HT计划[HT-1.0:0.885±0.046;HT-2.5:0.863(0.832,0.880),P均<0.05];HI也无统计学差异(0.311±0.043 vs 0.307±0.071,P=0.804),均低于HT计划(HT-1.0:0.373±0.053;HT-2.5:0.404±0.055,P均<0.05)。HA计划的GI最优(3.172±0.465),依次为VMAT[3.775(3.587,4.194)]、HT-1.0[4.250(4.000,4.711)]和HT-2.5(5.185±0.686)。HA计划的脑D_(mean)为四种计划中最低[(432.790±199.845)cGy]vs VMAT[434.900(336.850,534.600)cGy,HT-1.0(464.300±208.453)cGy,HT-2.5(545.400±242.035)cGy,P均<0.05]。对于脑剂量体积V_(5Gy)、V_(8Gy)、V_(10Gy)、V_(12Gy)、V_(15Gy)、V_(20Gy)、V_(25Gy)、V_(30Gy),HA和HT-1.0计划的V_(5Gy)近似(P=0.069),优于VMAT和HT-2.5计划(P均<0.05);HA计划在V_(8Gy)~V_(30Gy)均为最低,VMAT计划从V_(15Gy)开始优于HT-1.0,HT-2.5在所有剂量段脑受照体积最高。靶区间距对各技术间的差异影响不大。随靶区体积增加,HA与VMAT计划在V_(5Gy)、V_(8Gy)上差异减小,VMAT相对HT-1.0计划在V_(15Gy)以上的优势减弱,HT-1.0与HT-2.5计划在V_(5Gy)、V_(8Gy)和V_(25Gy)上差异减小。HA,VMAT,HT-2.5,HT-1.0计划出束时间依次增加。[结论]对于多发性脑转移瘤SRT,HA技术相比较VMAT和HT技术在适形性、均匀性、剂量梯度跌落、对脑的保护和治疗效率方面均表现更好。VMAT技术与HT-1.0技术在放射性脑坏死相关风险因素上表现近似,但前者治疗时间大幅缩短。展开更多
Objective:To evaluate the dosimetric quality of radiotherapy plans for nasopharyngeal carcinoma(NPC)using HyperArc(HA)technology.Methods:A retrospective analysis was conducted on 20 patients with initially diagnosed N...Objective:To evaluate the dosimetric quality of radiotherapy plans for nasopharyngeal carcinoma(NPC)using HyperArc(HA)technology.Methods:A retrospective analysis was conducted on 20 patients with initially diagnosed NPC who had received TomoTherapy(TOMO)treatment.Treatment plans were redesigned using HA technology on the Eclipse planning system.Dosimetric parameters and verification passing rates were collected to assess the dosimetric quality of target coverage and organ-at-risk(OAR)sparing in both sets of plans.Paired t-tests or Rank-Sum tests were used to compare the dosimetric parameters between the two plans.Results:For the planning target volumes(PTVs),the target coverage in both plans reached 95%.Compared with the TOMO plans,the HA plans exhibited a steeper dose fall-off for PTV_(69.75Gy)(P<0.05).However,the conformity index(CI)of the HA plans(0.75)was slightly lower than that of the TOMO plans(0.81,P<0.05).The homogeneity index(HI)was better in the TOMO plans,with statistically significant differences for PTV69.75Gy and PTV55.80Gy(P<0.05).Moreover,the HA plans had better sparing,particularly for the optic chiasm,optic nerves,and parotid glands(P<0.05),while no statistically significant differences were observed for other critical structures such as the brainstem,spinal cord,and temporal lobes(P>0.05).Additionally,the average beam-on time for the HA plans(252 s)was shorter than that of the TOMO plans(326 s,P<0.05).The mean gamma passing rate at 3%/2 mm for all plans exceeded 98%.Conclusions:Radiotherapy plans for NPC based on HA technology exhibit excellent dosimetric quality,providing good target coverage,rapid dose fall-off,and effective protection of adjacent critical organs.展开更多
文摘Objective:To assess the dosimetric performance of HyperArc and volumetric modulated arc radiotherapy(VMAT)techniques,using either full or ipsilateral arcs,for the radiotherapy of unilateral temporal lobe tumor,in order to quantify and analyze differences among these planning approaches using various dosimetric parameters.Methods:This retrospective study reviewed 30 patients with unilateral temporal lobe tumors treated with radiotherapy in the Department of Radiation Oncology,Shenzhen People's Hospital from August 2020 to December 2023.Using the Eclipse treatment plan system with the Truebeam machine model,HyperArc and VMAT plans were designed with full or ipsilateral arcs,respectively Dosimetric parameters for the planning target volume(PTV)and organs at risk(OARs)were computed and analyzed.Additionally,the monitor units(MU)of four types of plans were calculated for consideration of rays utilization and delivery efficiency.Results:HyperArc demonstrated superior dosimetric performance for PTV and OARs compared to VMAT(P<0.05),with exceptions noted for the low dose volume(V5 Gy)of the healthy brain and mean dose of ipsilateral cochlea.Ipsilateral arcs and full arcs showed similar efficacy in sparing OARs adjacent to PTV.Furthermore,full arcs improved PTV conformity compared with ipsilateral arcs(P<0.05),while ipsilateral arcs reduced the dose to contralateral OARs,mean dose and the middle-to-low dose volume of the healthy brain(P<0.05).Regarding MU,HyperArc(full)plans exhibited the minimum values among the four plan types,with overall MU for HyperArc plans being less than those for VMAT.Conclusions:This study not only highlights the outstanding performance of the HyperArc technique with respect to VMAT but also underscores the advantages of employing ipsilateral arcs over full arcs in the radiotherapy of unilateral temporal lobe tumor.Additionally,the HyperArc technique demonstrated higher efficiency of ray utilization and delivery.The findings of this study can aid in selecting appropriate techniques and guiding arcs arrangements for the radiotherapy of unilateral temporal lobe tumor.
文摘Objective:To assess the performance and advantages of HyperArc for radiotherapy of multiple brain metastases with dosimetric parameters with respect to coplanar volumetric modulated arc radiotherapy(c-VMAT),and characterize implicit correlations between tumor features and dosimetric parameters.Methods:This retrospective study involved 40 patients with multiple brain metastases(4–16 tumors,12.8–240.8 cm3)who received simultaneous radiotherapy at the Department of Radiation Oncology,Shenzhen People's Hospital from January 2019 to December 2022.Both HyperArc and c-VMAT plans were designed by the same and qualified physicist using the Eclipse system with Truebeam.A single isocenter and a 6 MV flattening filter-free(6FFF)photon beam were used for radiotherapy of multiple brain metastases in each plan.Dosimetric parameters of tumors and organs at risk(OARs)were compared between HyperArc and c-VMAT plans.Corre-lations between tumor features(number and volume)and dosimetric parameters were revealed and analyzed.Furthermore,monitor units(MUs)of both plan types were recorded to assess rays utilization and delivery efficiency.Results:Compared to c-VMAT plans,HyperArc plans achieved higher maximum dose(D_(max))(5.23%,t=7.87,P<0.01),but lower minimum dose(Dmin)(3.94%,t=-2.12,P=0.04)and mean dose(D_(mean))(1.05%,t=-3.29,P<0.01)for planning gross tumor volumes(PGTVs).The conformity index(CI),homogeneity index(HI),gradient index(GI)and R50%of PGTVs with HyperArc were better than those with c-VMAT,with the improve-ments of 20.78%,1.68%,19.83%and 36.20%,respectively(P<0.01).The dosimetric parameters of OARs were significantly improved in HyperArc plans compared to c-VMAT plans.Specifically,the D_(max)and the D_(mean)to the brainstem decreased by 16.14%and 11.37%,respectively.The D_(max)for eye_L decreased by 16.88%,for eye_R decreased by 11.67%,for optical nerve_L decreased by 12.56%,and for chiasm decreased by 18.12%.Few correlations were observed between the differences of CI/HI/GI/R50%and the number of PGTVs between the two plan types.Whereas,regression analysis indicated that the differences of CI/GI/R50%were negatively correlated with the volume of PGTVs,respectively.Moreover,although HyperArc plans reduced the MUs by 4.74%compared to c-VMAT,no significant difference was observed(P>0.05).Conclusions:This study demonstrates the promising performance of HyperArc for radiotherapy of multiple brain metastases,including better dose conformity for the tumors,more rapid dose drop and less dose spillage outside the tumors area,effective reduction of dose bridges among close tumors,and sparing OARs.It also reveals the correlations between the number or volume of tumors and dose parameters,which can help optimize the use of HyperArc and predict clinical benefits.
文摘[目的]分析不同放疗技术在多发性脑转移瘤立体定向放射治疗(stereotactic radiotherapy,SRT)中的剂量学差异。[方法]回顾性分析上海交通大学医学院附属瑞金医院2022年4月至9月多发性脑转移瘤10例病例,处方剂量35 Gy/5 f,分别采用容积弧形调强放射治疗技术(volumetric modulated arc therapy,VMAT),单中心非共面弧形调强放射治疗技术(HyperArc,HA),螺旋断层放射治疗(helical tomotherapy,HT)技术生成4种计划:VMAT,HA,使用1.0 cm射野宽度的HT(helical tomotherapy,1.0 cm field width,HT-1.0)和使用2.5射野宽度的HT(helical tomotherapy,2.5cm field width,HT-2.5)计划,比较4种计划的靶区适形性指数(conformal index,CI)、均匀性指数(homogeneity index,HI)、剂量梯度跌落指数(gradient index,GI),以及危及器官(organ at risk,OAR)包括脑干、左右晶体、左右视神经的最大剂量D_(max),脑平均剂量D_(mean)以及脑剂量体积V_(5Gy),V_(8Gy),V_(10Gy),V_(12Gy),V_(15Gy),V_(20Gy),V_(25Gy),V_(30Gy),并统计出束时间。探究靶区体积和靶区间距对各技术间脑剂量学参数差异的影响。[结果]VMAT和HA计划的CI无统计学差异(0.928±0.015 vs 0.928±0.008,P=0.980),均高于HT计划[HT-1.0:0.885±0.046;HT-2.5:0.863(0.832,0.880),P均<0.05];HI也无统计学差异(0.311±0.043 vs 0.307±0.071,P=0.804),均低于HT计划(HT-1.0:0.373±0.053;HT-2.5:0.404±0.055,P均<0.05)。HA计划的GI最优(3.172±0.465),依次为VMAT[3.775(3.587,4.194)]、HT-1.0[4.250(4.000,4.711)]和HT-2.5(5.185±0.686)。HA计划的脑D_(mean)为四种计划中最低[(432.790±199.845)cGy]vs VMAT[434.900(336.850,534.600)cGy,HT-1.0(464.300±208.453)cGy,HT-2.5(545.400±242.035)cGy,P均<0.05]。对于脑剂量体积V_(5Gy)、V_(8Gy)、V_(10Gy)、V_(12Gy)、V_(15Gy)、V_(20Gy)、V_(25Gy)、V_(30Gy),HA和HT-1.0计划的V_(5Gy)近似(P=0.069),优于VMAT和HT-2.5计划(P均<0.05);HA计划在V_(8Gy)~V_(30Gy)均为最低,VMAT计划从V_(15Gy)开始优于HT-1.0,HT-2.5在所有剂量段脑受照体积最高。靶区间距对各技术间的差异影响不大。随靶区体积增加,HA与VMAT计划在V_(5Gy)、V_(8Gy)上差异减小,VMAT相对HT-1.0计划在V_(15Gy)以上的优势减弱,HT-1.0与HT-2.5计划在V_(5Gy)、V_(8Gy)和V_(25Gy)上差异减小。HA,VMAT,HT-2.5,HT-1.0计划出束时间依次增加。[结论]对于多发性脑转移瘤SRT,HA技术相比较VMAT和HT技术在适形性、均匀性、剂量梯度跌落、对脑的保护和治疗效率方面均表现更好。VMAT技术与HT-1.0技术在放射性脑坏死相关风险因素上表现近似,但前者治疗时间大幅缩短。
基金National Natural Science Foundation of China(No.62305060)Startup Fund for Scientifc Research,Fujian Provincial Health Technology Project(No.2023GGA053)+2 种基金Joint Funds for the Innovation of Science and Technology,Fujian Province(No.2021Y9192)Fujian Provincial Clinlical Research Center for Cancer Radiotherapy and Immunotherapy(No.2020Y2012)Scientific Research Foundation of Fujian Cancer Hospital(No.2023YN04).
文摘Objective:To evaluate the dosimetric quality of radiotherapy plans for nasopharyngeal carcinoma(NPC)using HyperArc(HA)technology.Methods:A retrospective analysis was conducted on 20 patients with initially diagnosed NPC who had received TomoTherapy(TOMO)treatment.Treatment plans were redesigned using HA technology on the Eclipse planning system.Dosimetric parameters and verification passing rates were collected to assess the dosimetric quality of target coverage and organ-at-risk(OAR)sparing in both sets of plans.Paired t-tests or Rank-Sum tests were used to compare the dosimetric parameters between the two plans.Results:For the planning target volumes(PTVs),the target coverage in both plans reached 95%.Compared with the TOMO plans,the HA plans exhibited a steeper dose fall-off for PTV_(69.75Gy)(P<0.05).However,the conformity index(CI)of the HA plans(0.75)was slightly lower than that of the TOMO plans(0.81,P<0.05).The homogeneity index(HI)was better in the TOMO plans,with statistically significant differences for PTV69.75Gy and PTV55.80Gy(P<0.05).Moreover,the HA plans had better sparing,particularly for the optic chiasm,optic nerves,and parotid glands(P<0.05),while no statistically significant differences were observed for other critical structures such as the brainstem,spinal cord,and temporal lobes(P>0.05).Additionally,the average beam-on time for the HA plans(252 s)was shorter than that of the TOMO plans(326 s,P<0.05).The mean gamma passing rate at 3%/2 mm for all plans exceeded 98%.Conclusions:Radiotherapy plans for NPC based on HA technology exhibit excellent dosimetric quality,providing good target coverage,rapid dose fall-off,and effective protection of adjacent critical organs.
