不同区域影像配准对鼻咽癌计划靶区外扩的影响  

Multiple Regions of Interests Analysis in Nasopharyngeal Carcinoma: Effect on Margins of Planning Target Volume (PTV)

作　　者：马广栋[1] 洪莉[2] 王陆洲[1] 王亮和[1] 吴冰[1] 付敬国[1] 

机构地区：[1]武汉大学人民医院放疗科,武汉430060 [2]武汉大学人民医院妇2科,武汉430060

出　　处：《医疗卫生装备》2013年第5期66-68,共3页Chinese Medical Equipment Journal

摘　　要：目的：研究4种不同区域影像配准方法对鼻咽癌放疗计划设计时PTV的外放距离的影响,确定本中心鼻咽癌患者计划靶区各解剖外扩范围参考值。方法：选择颅底（A方法）、颈椎1~3（B方法）、下颌骨（C方法）和整体配准（D方法）4种影像配准方法进行CT和锥形束CT（cone beam CT,CBCT）配准,确定三维方向上的摆位误差,再由靶区外扩公式计算前后、头脚、左右3个方向上的计划靶区外扩值。结果：不同解剖区域影响配准方法产生的PTV外扩值有所不同,A方法配准所得外扩距离最小,D方法次之,C方法较大。4种配准方法的前后、头脚、左右3个方向的外扩距离分别为1.7、4.5、1.8 mm,3.1、5.3、1.4 mm,1.8、5.5、1.1 mm,2.3、4.1、1.1 mm。A、B、C、D 4种不同区域影像配准方法的头脚方向外扩距离都较其他方向大,4种方法外扩值均超过4 mm。将A、B、C 3种方法的摆位误差分别与D方法比较发现,A、C方法前后方向和C方法头脚方向有统计学意义（P〈0.05）。结论：患者头脚方向活动度大导致其外扩距离增大。在鼻咽癌靶区外扩时可以考虑不同解剖区域采用不同的外扩距离。Objective To study the effect on the margins of planning target volume（PTV） in the nasopharyngeal carcinoma （NPC） with four different image matching methods, and to make sure the four margins of PTV in NPC in Department of Radiation Oncology in People＇s Hospital of Wuhan University.Methods The skull（A）, cervicall-3（B）, mandible（C） and the whole image（D） methods were chosen to do the image matching on CT images and cone beam CT images, and the setup errors were analyzed, then the formula was used to calculate the margins on directions of front-rear, head-foot, and right-left,Results Different image matching methods brought different outer values on the planning target volume. The outer value of A method was low, the value of D method was lower than A＇s, and the value of C method was the highest. The outer values of the four methods in three directions were 1.7 mm and 4.5 mm and 1.8 mm, 3.1 mm and 5.3 mm and 1.4 ram, 1.8 mm and 5.5 mm and 1.1 ram, 2.3 mm and 4.1 mm and 1.1 mm, respectively. The expansion value of head-foot direction was higher than the other directions of A, B, C and D image matching methods. When the positioning errors by A, B and C methods compared with that by D method respectively, the front-rear ones by A and C, and right-left one by C were statistically significant（P〈O.05）.Conclusion High activity of the patients at head-foot direction leads to its external expansion distance increased. Different external expansion distances can be determined according to the anatomical regions when nasopharyngeal target expansion performed.

关 键 词：影像配准方法 鼻咽癌 外扩距离 

分 类 号：R739.63[医药卫生—肿瘤]