本文選題：Varian + clinac-IX加速器�。� 參考：《南京航空航天大學》2016年博士論文

【摘要】：放射治療的理想目標是僅在腫瘤部位產(chǎn)生劑量沉積,而正常器官組織無劑量沉積�，F(xiàn)代放療技術雖然還沒有達到此種水平,但計算機技術的發(fā)展所帶來的現(xiàn)代精確放療技術朝此理想化目標跨越了一大步。精確放療其核心在于“精確定位、精確計劃設計、精確治療”。為實現(xiàn)精確放射治療,在放射物理層面需要解決以下三個問題:如何確保放射劑量投射準確;針對不同腫瘤患者選擇最優(yōu)的放射治療技術,如何設計出最優(yōu)化的放射治療計劃;以及如何確保放射治療計劃能準確實施。本文旨在利用江蘇省蘇北人民醫(yī)院放療科Varian clinac-IX醫(yī)用電子直線加速器,及配套使用的Varian Eclipse放射治療計劃系統(tǒng)、指型電離室、MatriXX劑量儀、二維電離室矩陣和COMPASS三維驗證系統(tǒng)等設備所構成的完整放射治療體系,對以上三方面的問題分別展開研究。研究內(nèi)容和結論如下:首先,為確保射線投射準確,從以下四個方面進行了研究:(1)對高能X射線和電子束在水中吸收劑量的測量與計算方法進行研究,確保射線“質(zhì)”的準確。研究結果表明,用指型電離室在水模體中測量,并使用IAEA(International Atomic Energy Agency)277號報告的計算方法得出在有效測量點的吸收劑量值與標準計算值之間的誤差在0.17%~0.54%之間,滿足國家規(guī)定(≤2.0%)的要求,研究指出了加速器輸出射線的能量大小是準確的;(2)研究加速器質(zhì)量保證工作中常見的三種電離室(0.01 cm~3、0.125 cm~3以及0.6 cm~3)的劑量響應特性,了解其性能特點,確保劑量監(jiān)測的準確,從而能保證射線出束“量”的準確;(3)研究多葉準直器參數(shù)對射線傳輸?shù)挠绊?并將這些參數(shù)引入到治療計劃系統(tǒng)中,通過TPS計算和實測比較得出,80%等劑量線面積重合度都大于95%,曲線的分離度均小于3 mm,研究指出了測量多葉準直器(Multileaf Collimator,MLC)的參數(shù)是保證射線傳輸和劑量計算準確性的必要條件;(4)研究IGRT全碳纖維治療床對射線投射的影響,研究結果表明,IGRT全碳纖維治療床對6 MV X線的衰減因子在0.981~0.997,對15 MV X線的衰減因子在0.984~0.999,所以設計放療計劃時必須使用虛擬床模式,確保當加速器機架旋轉(zhuǎn)至IGRT全碳纖維治療床的斜下方或正下方時,治療床對射線的衰減可以得到與治療計劃系統(tǒng)(treatment planning system,TPS)的補償修正,保證射線投射準確。其次,針對三維適形放療、固定野調(diào)強放療和容積旋轉(zhuǎn)調(diào)強放療這三種目前主流的放療技術,分別以頭頸部的鼻咽癌、胸部的乳腺癌、腹部盆腔的宮頸癌、多中心放療的全中樞神經(jīng)系統(tǒng)放療以及危機器官在治療靶區(qū)內(nèi)的保護海馬的全腦照射為例,進行放療技術的比較劑量學研究,其中鼻咽癌、宮頸癌以及海馬保護全腦照射都是進行調(diào)強和旋轉(zhuǎn)容積調(diào)強放療兩種放療技術的劑量學參數(shù)比較研究,而乳腺癌則是這三種放療技術的劑量學參數(shù)比較研究,全中樞神經(jīng)系統(tǒng)則采用三維適形放療和調(diào)強放療比較研究。研究結果表明,旋轉(zhuǎn)容積調(diào)強放療技術能獲得更好的靶區(qū)劑量分布和更低的危及器官劑量受量,同時治療跳數(shù)MU和治療時間T更短,但旋轉(zhuǎn)容積調(diào)強放療技術對加速器自身的穩(wěn)定性要求較高,并且優(yōu)化過程耗時較長,降低了治療的效率。另一方面,以宮頸癌5野調(diào)強計劃為例,研究四組條件變量對劑量學參數(shù)的影響,這些條件變量包括X線能量(6 MV和15 MV)、治療體位(仰臥位和俯臥位)、MLC調(diào)強方式(動態(tài)和靜態(tài))、劑量計算算法包括各向異性分析算法和筆形束卷積算法,研究結果表明,最佳的條件變量應是俯臥體位、各向異性算法(Anisotropic Analytical Algorithm,AAA)劑量算法、MLC動態(tài)調(diào)強滑窗以及能量為15 MV的高能X線。最后,分析劑量驗證和位置驗證的必要性。一方面,利用德國IBA公司的MatriXX、COMPASS劑量驗證系統(tǒng)的技術優(yōu)勢,以食管癌為例進行劑量驗證研究。研究結果表明,食管癌等中心處絕對劑量能夠很好的與TPS達到一致;靶區(qū)和危及器官的γ通過率均在97%以上,從PD(Percent Different)值來看,GTV(Gross Tumor Volume)、CTV(Clinical Target Volume)、PTV(Planning Target Volume)的D95%、Dmean平均差異在2%以內(nèi);脊髓D1%平均差異2.04%;左肺和右肺的V5-30以V10為界差異呈逐漸增大趨勢,處于1.5%以內(nèi);心臟V20-40差異也呈逐漸增大趨勢,平均值差異為2.68%。另一方面,通過分析千伏級的錐形束計算機斷層掃描的技術優(yōu)勢,并以肺癌容積旋轉(zhuǎn)調(diào)強(Volumetric Modulated Arc Therapy,VMAT)計劃為例進行位置驗證研究。研究結果表明,.患者在x、y、z軸上的平均擺位誤差分別為(0.05±0.16)、(0.09±0.32)、(-0.02±0.13)cm;系統(tǒng)誤差在左右、頭腳、前后方向分別為:0.28、0.37、0.25 cm;隨機誤差左右、頭腳、前后方向分別為0.16 cm、0.32 cm、0.13 cm;CTV在x、y、z三個方向上的外擴值分別為0.82 cm、1.16 cm、0.72 cm�？傊�,在射線投射準確性方面,本文的研究結果解釋了Varian clinac-IX加速器系統(tǒng)在哪些方面是如何對射線的準確投射產(chǎn)生影響,而了解這種影響是進行精確放療的基礎;在計劃優(yōu)化設計方面,本文的研究結果解決了各種典型病例的計劃最優(yōu)化設計方法,即獲得滿意的靶區(qū)劑量分布的同時,大大降低了危及器官和正常組織的受量;在劑量驗證和位置驗證研究方面,本文的研究分析了驗證的必要性,提供了臨床上驗證的具體方法,可為臨床腫瘤放射物理應用方面提供參考依據(jù)。
[Abstract]:The ideal target of radiation therapy is to produce dose deposition only in the tumor site, and the normal organ tissue is no dosed. Although modern radiotherapy technology has not yet reached this level, the modern precise radiotherapy technology brought by the development of computer technology has made a great stride in this ideal target. The core of accurate radiotherapy is "fine determination". In order to achieve accurate radiation therapy, the physical level of radiation needs to solve three problems: how to ensure accurate radiation dose projection, how to select optimal radiotherapy for different cancer patients, how to design the optimal radiotherapy plan, and how to ensure the radiation therapy plan The purpose of this study is to make use of the Varian clinac-IX medical electronic linear accelerator of the Jiangsu Subei People's Hospital, and the Varian Eclipse radiotherapy planning system, the integrated radiation therapy system, such as the type ionization chamber, the MatriXX dosimeter, the two-dimensional ionization chamber matrix and the COMPASS three-dimensional verification system, and so on. The following three aspects are studied respectively. The contents and conclusions are as follows: first, to ensure the accuracy of the ray projection, the following four aspects are studied: (1) the measurement and calculation of the absorption dose of high energy X rays and electron beams in the water are studied to ensure the accuracy of the line "quality". The results show that the finger type ionization is used. The chamber is measured in the water body and uses the calculation method of IAEA (International Atomic Energy Agency) 277 report to conclude that the error between the absorbed dose value of the effective measurement point and the standard calculated value is between 0.17%~0.54%, and satisfies the requirements of the national regulations (less than 2%), and the study indicates that the energy of the output ray of the accelerator is accurate. 2) to study the dose response characteristics of three kinds of ionization chambers (0.01 cm~3,0.125 cm~3 and 0.6 cm~3) common in the quality assurance work of the accelerator, to understand its performance characteristics, to ensure the accuracy of the dose monitoring, and to ensure the accuracy of the ray emission "quantity"; (3) to study the influence of the parameters of the multi leaf straightener on the ray transmission, and to introduce these parameters into the system. In the treatment planning system, through the comparison of TPS calculation and measurement, the area recoincidence of 80% equal dose lines is more than 95% and the separation degree of the curve is less than 3 mm. The study indicates that the parameters of measuring the Multileaf Collimator (MLC) are the necessary conditions to ensure the accuracy of the ray transmission and dose calculation; (4) the study of the treatment of IGRT total carbon fiber treatment. The effect of bed on radiographic projection shows that the attenuation factor of the IGRT total carbon fiber treatment bed for 6 MV X ray is at 0.981~0.997, and the attenuation factor for 15 MV x x is 0.984~0.999, so the virtual bed mode must be used when designing the radiotherapy plan to ensure that when the accelerator frame rotates below the IGRT full carbon fiber treatment bed, it is under or right below. The radiation attenuation of the treatment bed can be compensated with the compensation correction of the treatment planning system (TPS) to ensure the accuracy of the ray projection. Secondly, three current mainstream radiotherapy techniques, such as three-dimensional conformal radiotherapy, fixed field intensity modulated radiation therapy and volume rotation intensity modulated radiation therapy, are used in the head and neck nasopharyngeal carcinoma and breast breast cancer, respectively. Cervical cancer of the pelvic cavity, the whole central nervous system radiotherapy with multi center radiotherapy, and the whole brain irradiation of the crisis organs in the target area for the protection of the whole brain of the hippocampus, the comparative dosimetry study of the radiotherapy technology is carried out. The two kinds of radiation therapy for nasopharyngeal carcinoma, cervical cancer and the whole brain irradiation of the hippocampus are both intensity modulated and rotating volume intensity modulated radiation therapy. The dosimetry parameters of the technology are compared, while breast cancer is a comparative study of the dosimetry parameters of these three kinds of radiotherapy techniques, and the whole central nervous system is compared with three dimensional conformal radiotherapy and intensity modulated radiation therapy. The results show that the rotational volume intensity modulated radiation therapy can obtain better target dose distribution and lower endanger organ dose. At the same time, the dose of MU and the treatment time T are shorter, but the rotation volume intensity modulated radiation therapy has a high requirement for the stability of the accelerator itself, and the optimization process takes a long time and reduces the efficiency of the treatment. On the other hand, the effect of the four condition variables on the dosimetric parameters is studied with the 5 field intensity adjustment plan of cervical cancer. These conditions change. The amount of X-ray energy (6 MV and 15 MV), the treatment of body position (supine position and prone position), MLC intensity modulation (dynamic and static), the dose calculation algorithm including the anisotropic analysis algorithm and the pen convolution algorithm. The results show that the best condition variable should be the prone body position, the anisotropy algorithm (Anisotropic Analytical Algorithm, AAA) dose The algorithm, MLC dynamic sliding window and high energy X-ray with energy of 15 MV. Finally, it analyzes the necessity of dose verification and location verification. On the one hand, using the technical advantage of the MatriXX, COMPASS dose verification system of the German IBA company, a dose verification study is conducted in the case of esophageal cancer. The results show that the absolute dose at the center of esophageal cancer can be done. The rate of gamma passing in the target area and endanger organ was above 97%. From the value of PD (Percent Different), the average difference between GTV (Gross Tumor Volume) and CTV (Clinical Target Volume) was within 2%; the average difference between the spinal cord and the left lung and the right lung was 2.04%. The trend of V20-40 is within 1.5%, and the difference in heart is also gradually increasing. The difference of the average value is 2.68%. on the other hand, by analyzing the technical advantage of the cone beam computed tomography of the kilovolt level, and using the Volumetric Modulated Arc Therapy, VMAT program as an example for the research of the position verification. The results showed that the average error of the patient on the X, y and Z axis was (0.05 + 0.16), (0.09 + 0.32) and (-0.02 + 0.13) cm, the system error was around, the head and foot were 0.28,0.37,0.25 cm, the random error was left and right, the head and foot were divided into 0.16 cm, 0.32 cm, 0.13 cm, CTV in X, and 0.8, 0.8 2 cm, 1.16 cm, 0.72 cm. in all, in terms of the accuracy of the ray projection, the results of this article explain how the Varian clinac-IX accelerator system has an effect on the accurate projection of the ray, and the understanding of this effect is the basis for accurate radiotherapy; in the planned optimization design, the results of this paper have solved a variety of results. The optimal design method of a typical case, that is, to obtain a satisfactory dose distribution of the target area, greatly reduces the amount of endanger organs and normal tissues. In the field of dose verification and location verification, this study analyses the necessity of validation and provides a specific clinical validation method for clinical tumor radiation physics. Provide reference for the application.
【學位授予單位】：南京航空航天大學
【學位級別】：博士
【學位授予年份】：2016
【分類號】：R730.55;TL53

【相似文獻】

相關期刊論文 前5條

1 劉旭紅;陳曉;崔建國;李文輝;柏晗;;碳纖維腹板俯臥位固定技術在直腸癌調(diào)強放療中的應用[J];醫(yī)療裝備;2012年11期

2 高磊,呂慶文,李樹祥;一種調(diào)強放射治療計劃系統(tǒng)的研究[J];醫(yī)療衛(wèi)生裝備;2001年05期

3 孫鐵軍,馮念倫,唐世堯;近距離放射治療儀和適形調(diào)強放療機的探討[J];中國醫(yī)學裝備;2005年10期

4 張建英;江濤;;Pinnacle計劃系統(tǒng)調(diào)強放療驗證Gamma通過率的研究[J];中國醫(yī)療器械雜志;2011年06期

5 張金葆;;螺旋斷層放療系統(tǒng)的先進性評估分析[J];中國醫(yī)療設備;2009年04期

相關會議論文 前10條

1 任紅艷;;非小細胞肺癌化療同步適形調(diào)強放療的護理[A];中華護理學會全國精神科護理學術交流暨專題講座會議論文匯編[C];2009年

2 周立慶;戴建榮;胡逸民;;對一種簡化調(diào)強放療技術的系統(tǒng)評價[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

3 徐英杰;張永謙;符貴山;張可;戴建榮;;調(diào)強放療面劑量驗證結果分析[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

4 戴建榮;William Que;;最小化調(diào)強放療的葉片移動距離和凸凹槽效應[A];中國生物醫(yī)學工程學會第六次會員代表大會暨學術會議論文摘要匯編[C];2004年

5 劉明;;調(diào)強放療生物效應的動物實驗[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

6 吳欽宏;李高峰;;北京醫(yī)院調(diào)強放療經(jīng)驗[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

7 戴建榮;;調(diào)強放療的計劃設計[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

8 李玉;張海波;董丹;馮梅;;適形調(diào)強放療聯(lián)合緩釋化療粒子治療晚期肺癌的初步研究[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

9 李玉;張海波;董丹;馮梅;;適形調(diào)強放療聯(lián)合緩釋化療粒子治療晚期肺癌的初步研究[A];2007第六屆全國放射腫瘤學學術年會論文集[C];2007年

10 徐裕金;劉冠;王準;鄭曉;王躍珍;封巍;賴霄晶;周霞;白雪;馬紅蓮;張娜;王謹;胡曉;陳明;;局部晚期非小細胞肺癌同步加量調(diào)強放療的回顧性分析[A];第13屆全國肺癌學術大會論文匯編[C];2013年

相關重要報紙文章 前7條

1 付東紅邋通訊員 張航;治療癌癥調(diào)強放療效果明顯[N];健康報;2007年

2 孫朝陽 魏紋;一個患者三個瘤 調(diào)強放療一并除[N];中國醫(yī)藥報;2003年

3 天津市腫瘤醫(yī)院放射治療科 王平;調(diào)強放療“逆向設計”治腫瘤[N];科技日報;2007年

4 王繼榮;調(diào)強放療精確殺滅癌細胞[N];健康報;2006年

5 王平 王佩國;調(diào)強技術 讓放療精益求精[N];健康報;2007年

6 張明通 邱素芳;調(diào)強放療治復發(fā)鼻咽癌安全有效[N];健康報;2012年

7 魏紋;變“粗放”為“集約”[N];科技日報;2002年

相關博士學位論文 前5條

1 李軍;基于Varian clinac-IX直線加速器放療系統(tǒng)的技術分析和臨床劑量學研究[D];南京航空航天大學;2016年

2 江波;基于常規(guī)加速器的全身調(diào)強放療方法[D];北京協(xié)和醫(yī)學院;2010年

3 袁光文;圖像引導的調(diào)強放療在宮頸癌術后輔助放療中的應用[D];中國協(xié)和醫(yī)科大學;2009年

4 李永恒;早期乳腺癌保乳術后調(diào)強放療研究[D];北京大學;2008年

5 畢錫文;早期原發(fā)韋氏環(huán)NK/T細胞淋巴瘤調(diào)強放療的劑量學和臨床結果[D];北京協(xié)和醫(yī)學院;2013年

相關碩士學位論文 前10條

1 王偉平;調(diào)強放療在胰腺癌和宮頸癌治療中的應用研究[D];北京協(xié)和醫(yī)學院;2015年

2 霍雯;左乳癌保乳術后野中野調(diào)強和逆向調(diào)強放療的劑量學比較[D];石河子大學;2015年

3 杜霄勐;調(diào)強放療用于宮頸癌術后輔助治療的劑量學與回顧性臨床研究[D];北京協(xié)和醫(yī)學院;2015年

4 諶娜娜;宮頸癌限定盆骨骨髓調(diào)強放療的劑量學及臨床研究[D];河北醫(yī)科大學;2015年

5 楊威;不可手術切除胃癌調(diào)強放療同步XP方案療效對比分析[D];山西醫(yī)科大學;2015年

6 李U，

本文編號：1931928