3D打印个性化乳腺托架在乳腺癌调强放疗中应用初探

Application of 3D printed personalized breast bracket in IMRT for breast cancer

目的比较3D打印个性化乳腺托架和普通头枕在乳腺癌调强放疗中引起的摆位误差,分析3D打印个性化乳腺托架在乳腺癌调强放疗中的固定效果。方法选取2021年1月至7月32例乳腺癌患者,随机分为3D打印乳腺托架组和普通头枕组。两组均采用仰卧位、头偏向健侧,患侧手握抓杆同侧横杆、健侧手握对侧竖杆,均用热塑膜固定胸部及下颌。每周行锥形束CT扫描并按照配准感兴趣区域分别用乳腺/胸壁野、锁骨上下野、腋窝野三种靶区配准方式进行配准。分析两组左右、头脚、腹背3个方向的摆位误差。结果3D乳腺托架组在乳腺/胸壁野、锁骨上下野、腋窝野的左右、头脚、腹背3个方向摆位误差分别是(1.75±1.26)、(1.77±1.11)、(1.70±1.08)mm,(1.75±1.25)、(1.72±1.09)、(1.70±1.05)mm,(1.86±1.34)、(2.14±2.13)、(1.66±1.19)mm。普通头枕组在乳腺/胸壁野、锁骨上下野、腋窝野的左右、头脚、腹背3个方向摆位误差分别是(2.54±1.84)、(2.73±3.62)、(2.18±2.45)mm,(3.25±2.02)、(3.52±2.26)、(2.62±2.83)mm,(3.25±2.05)、(4.44±2.90)、(3.10±3.18)mm。两组摆位误差比较P均<0.05。结论使用3D打印个性化乳腺托架固定摆位误差小于普通头枕固定;在乳腺/胸壁野、锁骨上下野、腋窝野3个靶区摆位一致性方面,3D打印个性化乳腺托架优于普通头枕。

Objective By comparing the positioning errors caused by 3D printed personalized breast bracket and common headrest in intensity-modulated radiation therapy(IMRT),the fixation effect of 3D printed personalized breast bracket in IMRT was analyzed.Methods Thirty-two breast cancer patients from January to July 2021 were randomly divided into a the 3D printed breast bracket group and common headrest group.All patients in two groups were kept in supine position,head tilted to the healthy side,the affected hand held the grip bar on the same side of the horizontal bar,the healthy hand held the opposite side of the vertical bar,and the chest and mandible were fixed with thermoplastic film.CBCT scan was performed weekly,and gray level registration was carried out according to the three registration regions of interest:breast or chest wall field,supraclavicular and inferior field,and axillary field.The positioning errors in the left and right,head and foot,abdomen and back directions were analyzed between two groups.Results In the 3D printed breast bracket group,the positioning errors of breast or chest wall field,supraclavicular and inferior field and axillary field in the left and right,head and foot,abdomen and back directions were(1.75±1.26),(1.77±1.11)and(1.70±1.08)mm,(1.75±1.25),(1.72±1.09)and(1.70±1.05)mm,(1.86±1.34),(2.14±2.13)and(1.66±1.19)mm,respectively.In the common headrest group,the positioning errors of breast or chest wall field,supraclavicular and inferior field and axillary field in the left and right,the head and feet,the abdomen and back directions were(2.54±1.84),(2.73±3.62)and(2.18±2.45)mm,(3.25±2.02),(3.52±2.26)and(2.62±2.83)mm,(3.25±2.05),(4.44±2.90)and(3.10±3.18)mm,respectively.The positioning errors significantly differed between two groups(all P<0.05).Conclusions The positioning error of 3D printed personalized breast bracket fixation is less than that of common headrest fixation.The positioning consistency of 3D printed personalized breast bracket in the three target areas of breast or chest wall field,supraclavicular and inferior field and axillary field is better than that of common headrest.