CAJ | 학술논문

目的：分析千伏级锥体束CT （ KV-CBCT ）肝癌图像引导放疗摆位误差，为肝癌放疗计划靶区（PTV）的外放边界提供参考。方法应用医科达Synergy直线加速器治疗31例肝癌患者，KV-CBCT扫描采集的X线容积图像（ XVI）与计划CT图像的靶中心匹配，获得腹背（ X）、头脚（ Y）、左右（ Z）三个方向的线性误差x、y、z和绕X、Y、Z轴旋转形成的旋转误差u、v、w。由公式计算出肝癌临床靶区（ CTV）到计划靶区（ PTV）的外放边界值（ MPTV ）。结果共进行275次 CBCT 扫描，其在 X、Y、Z 方向上摆位误差 x、y、z 中位数分别为1．70 mm、1．30 mm、0．80 mm，旋转误差u、v、w分别为0．65°、0．38°、0．31°。 MPTV在X、Y、Z方向上分别为4．11 mm、8．49 mm、4．94 mm。结论采用KV-CBCT技术测量肝癌图像引导放疗的摆位误差，为肝癌放疗MPTV提供参考，提高了肝癌放疗的精准性。
목적：분석천복급추체속CT （ KV-CBCT ）간암도상인도방료파위오차，위간암방료계화파구（PTV）적외방변계제공삼고。방법응용의과체Synergy직선가속기치료31례간암환자，KV-CBCT소묘채집적X선용적도상（ XVI）여계화CT도상적파중심필배，획득복배（ X）、두각（ Y）、좌우（ Z）삼개방향적선성오차x、y、z화요X、Y、Z축선전형성적선전오차u、v、w。유공식계산출간암림상파구（ CTV）도계화파구（ PTV）적외방변계치（ MPTV ）。결과공진행275차 CBCT 소묘，기재 X、Y、Z 방향상파위오차 x、y、z 중위수분별위1．70 mm、1．30 mm、0．80 mm，선전오차u、v、w분별위0．65°、0．38°、0．31°。 MPTV재X、Y、Z방향상분별위4．11 mm、8．49 mm、4．94 mm。결론채용KV-CBCT기술측량간암도상인도방료적파위오차，위간암방료MPTV제공삼고，제고료간암방료적정준성。
Objective To analyze the set-up errors in image-guided radiation therapy for liver cancer guided with kilo-voitage cone beam computed tomography ( CBCT ) to calculate the referential safety margin of plan target volume ( PTV) .Methods Thirty-one patients with liver cancer were involved in the treatment with Elekta Synergy linear accelerator , the kilo-voltage CBCT-collected volume of X-ray images(XVI) was matched with the center of target of planning CT images to obtain the linearity errors(x,y,z) and the rotational errors(u,v,w) in three directions:back-belly(X),head-feet(Y),left-right (Z).The margin(MPTV) between clinical target volume(CTV) and PTV was calculated based on the formula .Results A total of 275 CBCT scans showed that in the X ,Y,Z directions,the mean linear errors ( x,y,z) were 1.70 mm, 1.30 mm,0.80 mm,respectively,and the rotational errors(u,v,w) were 0.65°,0.38°,0.31°,respectively.MPTV in three-dimensional directions(X,Y,Z) were 4.11 mm,8.49 mm,4.94 mm,respectively.Conclusion Kilo-voltage CBCT applied to evaluating the set-up errors of image-guided radiation therapy can provide the references for determining MPTV of radiotherapy for liver cancer ,which improves the accuracy of radiotherapy for liver cancer .