中国癌症杂志
中國癌癥雜誌
중국암증잡지
CHINA ONCOLOGY
2014年
7期
535-539
,共5页
陆维%许婷婷%许青%应红梅%胡超苏
陸維%許婷婷%許青%應紅梅%鬍超囌
륙유%허정정%허청%응홍매%호초소
千伏级锥形束CT%兆伏级电子射野影像系统%头颈部肿瘤%摆位误差
韆伏級錐形束CT%兆伏級電子射野影像繫統%頭頸部腫瘤%襬位誤差
천복급추형속CT%조복급전자사야영상계통%두경부종류%파위오차
Kilovoltage cone beam CT%Megavoltage electronic portal imaging device%Head and neck neoplasms%Setup error
背景与目的：随着放疗技术和设备的不断发展，鼻咽癌放射治疗已经进入了精确放疗时代，摆位误差成为影响放疗效果的非常重要的因素。本研究在千伏级锥形束CT(cone beam computed tomography， CBCT)与兆伏级电子射野影像系统(electronic portal imaging device，EPID)2种影像模式引导下治疗鼻咽癌，在头枕+头颈肩面膜、真空气垫+头颈肩面膜固定2种方式下的摆位误差分析比较。方法：随机选取40例鼻咽癌患者分成2组(头枕+头颈肩面膜组，真空气垫+头颈肩面膜固定组)，每组组内再分成CBCT扫描组和EPID验证组。将CBCT扫描图像与计划CT图像进行自动骨性配准、将EPID拍摄的正侧位片采用突出性骨性标志进行手动配准，分别得出x、y、z共3个线性方向上的摆位误差值，对获得的2组数据进行组内组间两两比较，采用t检验比较数据差异有无统计学意义。结果：头枕+头颈肩面膜组摆位后行CBCT扫描，在x、y、z方向上进行配准所得的平均误差分别为：x方向(0.67±2.01)mm、y方向(0.51±1.71)mm、z方向(0.57±2.04)mm；拍摄EPID验证片配准所得误差均值：x方向(0.69±2.19)mm、y方向(0.54±2.03)mm、z方向(0.61±2.11)mm。真空气垫+头颈肩面膜固定组摆位后行CBCT扫描，在x、y、z方向上进行配准所得的平均误差分别为：x方向(0.42±1.81)mm、y方向(0.33±1.55)mm、z方向(0.50±1.75)mm；拍摄EPID验证片配准误差均值：x方向(0.44±1.87)mm、y方向(0.43±1.70)mm、z方向(0.54±1.77)mm。采用头枕+头颈肩面膜组、真空气垫+头颈肩面膜固定组的误差数据差异均有统计学意义(P<0.05)。结论：2种不同的影像模式(CBCT与EPID)进行摆位误差的比对未见明显统计学差异，2种固定方式下头颈部真空气垫+头颈肩面膜固定的患者体位重复性更好。
揹景與目的：隨著放療技術和設備的不斷髮展，鼻嚥癌放射治療已經進入瞭精確放療時代，襬位誤差成為影響放療效果的非常重要的因素。本研究在韆伏級錐形束CT(cone beam computed tomography， CBCT)與兆伏級電子射野影像繫統(electronic portal imaging device，EPID)2種影像模式引導下治療鼻嚥癌，在頭枕+頭頸肩麵膜、真空氣墊+頭頸肩麵膜固定2種方式下的襬位誤差分析比較。方法：隨機選取40例鼻嚥癌患者分成2組(頭枕+頭頸肩麵膜組，真空氣墊+頭頸肩麵膜固定組)，每組組內再分成CBCT掃描組和EPID驗證組。將CBCT掃描圖像與計劃CT圖像進行自動骨性配準、將EPID拍攝的正側位片採用突齣性骨性標誌進行手動配準，分彆得齣x、y、z共3箇線性方嚮上的襬位誤差值，對穫得的2組數據進行組內組間兩兩比較，採用t檢驗比較數據差異有無統計學意義。結果：頭枕+頭頸肩麵膜組襬位後行CBCT掃描，在x、y、z方嚮上進行配準所得的平均誤差分彆為：x方嚮(0.67±2.01)mm、y方嚮(0.51±1.71)mm、z方嚮(0.57±2.04)mm；拍攝EPID驗證片配準所得誤差均值：x方嚮(0.69±2.19)mm、y方嚮(0.54±2.03)mm、z方嚮(0.61±2.11)mm。真空氣墊+頭頸肩麵膜固定組襬位後行CBCT掃描，在x、y、z方嚮上進行配準所得的平均誤差分彆為：x方嚮(0.42±1.81)mm、y方嚮(0.33±1.55)mm、z方嚮(0.50±1.75)mm；拍攝EPID驗證片配準誤差均值：x方嚮(0.44±1.87)mm、y方嚮(0.43±1.70)mm、z方嚮(0.54±1.77)mm。採用頭枕+頭頸肩麵膜組、真空氣墊+頭頸肩麵膜固定組的誤差數據差異均有統計學意義(P<0.05)。結論：2種不同的影像模式(CBCT與EPID)進行襬位誤差的比對未見明顯統計學差異，2種固定方式下頭頸部真空氣墊+頭頸肩麵膜固定的患者體位重複性更好。
배경여목적：수착방료기술화설비적불단발전，비인암방사치료이경진입료정학방료시대，파위오차성위영향방료효과적비상중요적인소。본연구재천복급추형속CT(cone beam computed tomography， CBCT)여조복급전자사야영상계통(electronic portal imaging device，EPID)2충영상모식인도하치료비인암，재두침+두경견면막、진공기점+두경견면막고정2충방식하적파위오차분석비교。방법：수궤선취40례비인암환자분성2조(두침+두경견면막조，진공기점+두경견면막고정조)，매조조내재분성CBCT소묘조화EPID험증조。장CBCT소묘도상여계화CT도상진행자동골성배준、장EPID박섭적정측위편채용돌출성골성표지진행수동배준，분별득출x、y、z공3개선성방향상적파위오차치，대획득적2조수거진행조내조간량량비교，채용t검험비교수거차이유무통계학의의。결과：두침+두경견면막조파위후행CBCT소묘，재x、y、z방향상진행배준소득적평균오차분별위：x방향(0.67±2.01)mm、y방향(0.51±1.71)mm、z방향(0.57±2.04)mm；박섭EPID험증편배준소득오차균치：x방향(0.69±2.19)mm、y방향(0.54±2.03)mm、z방향(0.61±2.11)mm。진공기점+두경견면막고정조파위후행CBCT소묘，재x、y、z방향상진행배준소득적평균오차분별위：x방향(0.42±1.81)mm、y방향(0.33±1.55)mm、z방향(0.50±1.75)mm；박섭EPID험증편배준오차균치：x방향(0.44±1.87)mm、y방향(0.43±1.70)mm、z방향(0.54±1.77)mm。채용두침+두경견면막조、진공기점+두경견면막고정조적오차수거차이균유통계학의의(P<0.05)。결론：2충불동적영상모식(CBCT여EPID)진행파위오차적비대미견명현통계학차이，2충고정방식하두경부진공기점+두경견면막고정적환자체위중복성경호。
Background and purpose: With the development of therapy equipments and technology, the treatment for nasopharyngeal carcinoma(NPC) has entered into the era of precision radiotherapy, and setup errors have become a very important factor affecting treatment effects. The purpose of this study was to analyze the set-up errors detected by the kilovoltage cone beam CT(EPID) and the megavoltage electronic portal imaging device(CBCT) using 2 kinds of different immobilization techniques (pillow+head neck shoulder mask and vacuum bag+head neck shoulder mask) for NPC patients. Methods:A total number of 40 NPC patients were randomly assigned into 2 groups (pillow+head neck shoulder mask group and vacuum bag+neck shoulder mask group). Then each group was further divided into CBCT scan group and EPID group for veriifcation before treatment delivery. We matched the EPID images with the DRRs and acquired the set-up errors in x, y, z axis. Setup errors of CBCT were calculated according to its matched and planned CT images in left-right (x), superior-inferior (y) and anterior-posterior (z) directions. Paired t-test was used to evaluate the differences. Results:In the pillow+head neck shoulder mask group, the set-up errors of CBCT in the x, y, z axis were x (0.67±2.01)mm, y (0.51±1.71)mm and z (0.57±2.04)mm, respectively. The errors of EPID were x (0.69±2.19)mm, y (0.54±2.03)mm and z (0.61±2.11)mm. In the vacuum bag+head neck shoulder mask group, the set-up errors of CBCT in the x, y, z axis were x (0.42±1.81)mm, y (0.33±1.55)mm and z (0.50±1.75)mm, respectively. The errors of EPID were x (0.44±1.87)mm, y (0.43±1.70)mm and z (0.54±1.77)mm. The vacuum bag+head neck shoulder mask ifxed technique was more accurate when compared to the pillow + head neck shoulder mask ifxation method (P<0.05). Conclusion:CBCT and EPID were similar in detecting set-up errors for the NPC patients. However, the vacuum bag+neck shoulder mask ifxed technique was more accurate when compared to the pillow+head neck shoulder mask ifxation method.
