MLC叶片厚度对颅内SRS逆向IMRT计划的影响评价

doi:10.3760/cma.j.issn.1004-4221.2018.01.008

摘要
图/表
参考文献()
相关文章 (15)
点击分布统计
下载分布统计

全文: PDF (0 KB) HTML (1 KB)
输出: BibTeX | EndNote (RIS) 背景资料

摘要目的比较微型MLC (2 mm叶片厚度)和普通MLC (10 mm叶片厚度)在颅内SRS逆向IMRT计划中的剂量分布差异。方法鉴于微型MLC开野小的特点,选取30例颅内最大直径<10 cm肿瘤进行比较,分别使用常规和微型MLC进行剂量学对比,保持所有计划优化参数一致,得到满足临床要求的逆向动态调强计划,T检验比较两种MLC条件下放疗计划中靶区和OAR受量。结果微型MLC和普通MLC相比,在靶区剂量分布方面前者优于后者(P=0.019),但D98、D95、D50、D3相近(P=0.774、0.650、0.170、0.080),而前者HI均值比后者低58.7%(P=0.000),CI均值比后者高20.1%(P=0.044);OAR受量前者均小于后者,其中脑干Dmean、Dmax均值前者均低于后者,分别为 10.0%、8.2%(P=0.768、0.753),右眼和左眼Dmean、Dmax均值前者低于后者,依次为16.5%、19.3%和21.4%、13.4%(P=0.572、0.775和0.734、0.630),左晶状体、右晶状体、左视神经、右视神经、视交叉Dmax均值前者均低于后者,依次为50.4%、24.1%、38.5%、27.8%、5.7%(P=0.172、0.467、0.521、0.740、0.899);正常组织PRV100、PRV50、PRV25 前者体积均≤后者(P=0.839、0.832、0.972)。结论微型MLC在颅内SRS逆向IMRT计划中优于普通MLC,其提高了靶区适形性,降低了OAR受量。

	服务

	把本文推荐给朋友
	加入我的书架
	加入引用管理器
	E-mail Alert
	RSS
	作者相关文章
	万欢
	陶丹
	杨曾晶
	龙文华
	黄娅丽
	黄慧
	龙志雄

关键词 ：立体定向外科, 多叶准直器, 剂量学

Abstract：Objective To compare the dosimetric effects of micro-multileaf collimator (MLC)(2 mm leaf width) and conventional MLC (10 mm leaf width) on inverse intensity-modulated radiotherapy (IMRT) in intracranial stereotactic radiosurgery (SRS). Methods In view of the fact that the micro-MLC has a small open field, 30 patients with intracranial tumor with a<10 cm diameter were enrolled in this study. Their inverse dynamic IMRT plans were established using conventional MLC (conventional group) and micro-MLC (micro group) with the same other conditions. The radiation doses to the target volume and the organs at risk (OAR) were compared between the two groups with t test. Results Compared with the conventional group, the micro group had a significantly better dose distribution in the target volume (P=0.019). However, there were no significant differences in D98, D95, D50, and D3 between the two groups (P=0.774,0.650,0.170,0.080). The micro group had a 58.7% lower mean homogeneity index and a 20.1% higher mean conformity index than the conventional group (P=0.000). The micro group had significantly lower radiation doses to OAR than the conventional group (P=0.044). The mean Dmean and Dmax of the brain stem in the micro group were 10.0% and 8.2%, respectively, lower than those in the conventional group (P=0.768,0.753). The mean Dmean and Dmax of the right eye and left eye in the micro group were 16.5%, 19.3%, 21.4%, and 13.4%, respectively, lower than those in the conventional group (P=0.572,0.775 and 0.734,0.630). The mean Dmax of the left lens, right lens, left optic nerve, right optic nerve, and optic chiasm in the micro group were 50.4%, 24.1%, 38.5%, 27.8%, and 5.7%, respectively, lower than those in the conventional group (P=0.172,0.467,0.521,0.740,0.899). The PRV100, PRV50, and PRV25 of the normal tissue in the micro group were no more than those in the conventional group (P=0.839,0.832,0.972). Conclusions In inverse IMRT in intracranial SRS, micro-MLC is better than conventional MLC because it can improve CI of the target volume and reduce the radiation doses to OAR.

Key words： Stereotactic radiosurgery Multi leaf collimator Dosimetry

收稿日期: 2017-07-07

通讯作者: 龙志雄,Email:longzhixiong@hotmail.com

引用本文:

万欢,陶丹,杨曾晶等. MLC叶片厚度对颅内SRS逆向IMRT计划的影响评价[J]. 中华放射肿瘤学杂志, 2018, 27(1): 40-43.

Wan Huan,Tao Dan,Yang Zengjing et al. Dosimetric effects of multileaf collimator leaf width on inverse intensity-modulated radiotherapy in intracranial stereotactic radiosurgery[J]. Chinese Journal of Radiation Oncology, 2018, 27(1): 40-43.

链接本文:

http://journal12.magtechjournal.com/Jweb_fszlx/CN/10.3760/cma.j.issn.1004-4221.2018.01.008 或 http://journal12.magtechjournal.com/Jweb_fszlx/CN/Y2018/V27/I1/40

[1] Benedict SH,Cardinale RM,Wu QW,et al. Intensity-modulated stereotactic radiosurgery using dynamic micro-multileaf collimation[J].Int J Radiat Oncol Biol Phys,2001,50(3):751-758.DOI:10.1016/S0360-016(01)01487-0
[2] Cardinale RM,Benedict SH,Wu QW,et al. A comparison of three stereotactic radiotherapy techniques;ARCS vs.noncoplanar fixed fields vs.intensity modulation[J].Int J Radiat Oncol Biol Phys,1998,42(2):431-436.DOI:10.1016/S0360-016(98)00206-5
[3] Yin FF,Ryu S,Ajlouni M,et al. A technique of intensity-modulated radiosurgery (IMRS) for spinal tumors[J].Med Phys,2002,29(12):2815-2822.DOI:10.1118/1.1521722
[4] Bortfeld T,Oelfke U,Nill S.What is the optimum leaf widthof a multileaf collimator?[J].Med Phys,2000,27(11):2494-2502.DOI:10.1118/1.1319524
[5] Ding MS,Newman F,Chen CH,et al. Dosimetric comparison between 3DCRT and IMRT using different multileaf collimators in the treatment of brain tumors[J].Med Dosim,2009,34(1):1-8.DOI:10.1016/j.meddos.2007.04.001
[6] Nill S,Tucking T,Munter MW,et al. Intensity modulated radiation therapy with multileaf collimators of different leaf widths:a comparison of achievable dose distributions[J].Radiother Oncol,2005,75(1):106-111.DOI:10.1016/j.radonc.2005.02.007
[7] Chang J,Yenice KM,Jiang K,et al. Effect of MLC leaf width and PTV margin on the treatment planning of intensity-modulated stereotactic radiosurgery (IMSRS) or radiotherapy (IMSRT)[J].Med Dosim,2009,34(2):110-116.DOI:10.1016/j.meddos.2008.06.002
[8] Wu QJ,Wang ZH,Kirkpatrick JP,et al. Impact of collimator leaf width and treatment technique on stereotactic radiosurgery and radiotherapy plans for intra-and extracranial lesions[J].Radiat Oncol,2009(6):4:3.DOI:10.1186/1748-717X-4-3
[9] 桑勇,陈维军,狄小云,等.多叶光栅叶片宽度对鼻咽癌剂量学的影响[J].中国医学物理学杂志,2014,31(6):5240-5243.Sang Y,Chen WJ,Di XY,et al. The dosimetric impact of multi leaf collimator leaf width on nasopharyngeal carcinoma intensity modulated radiotherapy[J].Chin J Med Phys,2014,31(6):5240-5243
[10] Nakamura JL,Verhey LJ,Smith V,et al. Dose conformity of gamma knife radiosurgery and risk factors for complications[J].Int J Radiat Oncol Biol Phys,2001,51(5):1313-1319.DOI:10.1016/S0360-3016(01)01757-6
[11] Paddick I.A simple scoring ratio to index the conformity of radiosurgical treatment plans:technical note[J].J Neurosurg,2000,93(3):219-222
[12] Tanyi JA,Kato CM,Chen Y,et al. Impact of the high-definition multileaf collimator on linear accelerator-based intracranial stereotactic radiosurgery[J].Br J Radiol,2011,84(1003):629-638.DOI:10.1259/bjr/19726857
[13] Meeks SL,Buatti JM,Bova FJ,et al. Treatment planning optimization for linear accelerator radiosurgery[J].Int J Radiat Oncol Biol Phys,1998,41(1):183-197.DOI:10.1016/S0360-3016(98)00044-3
[14] Wagner TH,Bova FJ,Friedman WA,et al. A simple and reliable index for scoring rival stereotactic radiosurgery plans[J].Int J Radiat Oncol Biol Phys,2003,57(4):1141-1149.DOI:10.1016/S0360-3016(03)01563-3