本文選題：CT + on　； 參考：《安徽醫(yī)科大學(xué)》2017年碩士論文

【摘要】：目的1.比較宮頸癌圖像引導(dǎo)放射治療(IGRT)中滑軌CT(CT on rail)與電子射野影像系統(tǒng)(EPID)測量的擺位誤差,評價(jià)CT on rail在宮頸癌IGRT中的應(yīng)用價(jià)值;2.比較CT on rail引導(dǎo)宮頸癌IGRT時(shí),膀胱不同的充盈狀態(tài)對靶區(qū)與危及器官(OAR)的劑量分布的影響。方法隨機(jī)選取在我院進(jìn)行宮頸癌調(diào)強(qiáng)放療(IMRT)的患者15例,每周先在膀胱充盈狀態(tài)下(定位前2小時(shí)排空膀胱并一次性飲水500ml)掃描一次EPID正側(cè)位片和CT on rail圖像,將EPID拍攝的正側(cè)位片與數(shù)字重建影像系統(tǒng)(DRR)進(jìn)行配準(zhǔn),CT on rail圖像與計(jì)劃CT圖像分別進(jìn)行灰度配準(zhǔn)和骨性配準(zhǔn),得到三組X(左右)、Y(頭腳)、Z(腹背)方向的線性擺位誤差,并計(jì)算各個(gè)方向的CTV-PTV外放間距(MPTV),然后排空膀胱,再進(jìn)行一次CT on rail圖像掃描,并將兩次所得CT圖像均傳送至三維治療計(jì)劃系統(tǒng)(TPS),進(jìn)行靶區(qū)勾畫及設(shè)計(jì)治療計(jì)劃,得到在膀胱充盈與空虛狀態(tài)下,兩組臨床靶區(qū)(CTV)與直腸、膀胱等危及器官(OAR)的劑量學(xué)參數(shù),最終所得數(shù)據(jù)進(jìn)行統(tǒng)計(jì)學(xué)分析。結(jié)果1.EPID,CT on rail骨性及灰度配準(zhǔn)三種方式測量的X軸擺位誤差分別為0.251±0.065,0.209±0.536,0.184±0.046cm,Y軸擺位誤差分別為0.379±0.044,0.256±0.060,0.204±0.051cm,Z軸擺位誤差分別為0.185±0.051,0.112±0.057,0.126±0.058cm,CT on rail灰度配準(zhǔn)組與骨性配準(zhǔn)所測擺位誤差均明顯小于EPID組(P0.05),灰度配準(zhǔn)組在X,Y軸的擺位誤差較骨性配準(zhǔn)組縮小,尤其在Y軸上(P0.05),兩者在Z軸的擺位誤差無明顯差別;三組在X軸的MPTV為0.67、0.56、0.49cm,Y軸的MPTV為0.98、0.68、0.54cm,Z軸的MPTV為0.50、0.32、0.35cm;2.CT on rail引導(dǎo)宮頸癌IGRT時(shí),膀胱充盈與空虛狀態(tài)相比,兩組的CTV平均劑量(CTV Dmean)分別為5057.50±91.09,5039.08±88.31c Gy,CTV最大劑量(CTV D2)分別為5353.50±64.20,5341.05±70.37 c Gy,兩組數(shù)據(jù)間無明顯差異(P0.05);兩組的膀胱平均劑量(膀胱Dmean)分別為3606.00±146.36,4093.00±151.81c Gy,V40%分別為36.50±5.16,49.70±8.51,V45%分別為24.75±6.42,27.28±6.63,V50%分別為12.42±2.23,12.90±2.42,其中膀胱Dmean、V40、V45有顯著差異(P0.05),膀胱V50無明顯差異(P0.05);兩組的直腸平均劑量(直腸Dmean)分別為3738.50±257.45,3804.00±309.18c Gy,直腸V40%分別為44.78±6.73,55.23±5.67,V45%分別為30.15±4.74,31.90±5.04,V50%分別為5.52±0.27,5.64±0.45,其中直腸Dmean,V40,V45的差異顯著(P0.05),直腸V50無明顯差異(P0.05)。結(jié)論1.在宮頸癌IGRT中,CT on rail較EPID能更好地測量擺位誤差,使放療靶區(qū)更為精準(zhǔn);在CT on rail引導(dǎo)宮頸癌IGRT時(shí),采用灰度配準(zhǔn)優(yōu)于骨性配準(zhǔn),根據(jù)CT on rail灰度配準(zhǔn)測量的擺位誤差計(jì)算的X,Y,Z方向的MPTV可作為本中心宮頸癌放射治療的參考;2.CT on rail引導(dǎo)宮頸癌IGRT時(shí),膀胱充盈狀態(tài)有利于對直腸、膀胱等OAR的保護(hù),在分次治療間應(yīng)盡量保持膀胱充盈狀態(tài)。
[Abstract]:Objective 1. To evaluate the application value of CT on rail in cervical cancer by comparing the error between CT on rail) and electron field imaging system (EPID) in cervical cancer guided radiation therapy (IGRT). To compare the effects of different filling states of bladder on the dose distribution of target area and endangered organ (OAR) in cervical carcinoma guided by CT on rail. Methods Fifteen patients with cervical cancer undergoing intensity modulated radiotherapy (IMRT) were randomly selected and scanned with positive and lateral CT scan and CT on rail images in the condition of bladder filling (emptying bladder 2 hours before positioning and one-time drinking 500ml) every week. Three groups of linear pendulum errors in the direction of X (left and right) Y (head and foot) and Z (ventral dorsal) are obtained by registration of CT on rail images and planned CT images with digital reconstruction image system (DRR) taken by EPID, respectively. The CTV-PTV outer space was calculated, then the bladder was emptied, the CT on rail images were scanned again, and the two CT images were transmitted to the three dimensional treatment Planning system (TPS) to draw the target area and design the treatment plan. The dosimetric parameters of clinical target area (CTV), rectum and bladder (OAR) were obtained under the condition of bladder filling and emptiness. The final data were analyzed statistically. Results 1. The axial pendulum errors measured by EPID-CT on rail bone quality and gray level registration were 0.251 鹵0.065 鹵0.209 鹵0.536U 0.184 鹵0.046 cm ~ (-1) Y and 0.379 鹵0.044 鹵0.060 ~ 0.256 鹵0.060 ~ 0.204 鹵0.051 cm Z axis pendulum errors of 0.185 鹵0.051 鹵0.112 鹵0.057 ~ 0.126 鹵0.058 cm CT on rail gray level registration group respectively. In the EPID group (P0.05), the error of the shafts of the gray level registration group was smaller than that of the bone registration group. Especially on the Y axis (P0.05), there was no significant difference between the two groups in the Z axis, and in the three groups, the MPTV of the X-axis was 0.670.56 ~ 0.49 cm ~ (-1) Y axis was 0.98 ~ 0.68 ~ 0.54 cm ~ (-1) Z axis was 0.50 ~ 0.32 ~ 0.35 cm ~ (35) cm ~ (2) CT on rail guiding cervical carcinoma, the bladder filling was compared with the emptiness state. 涓ょ粍鐨凜TV騫沖潎鍓傞噺(CTV Dmean)鍒嗗埆涓，

本文編號：2100292