Radiotherapy Center, Guangxi Medical University Cancer Hospital, Nanning, Guangxi 530021, China.
Pediatric Department, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, China.
J Healthc Eng. 2021 Nov 11;2021:1463299. doi: 10.1155/2021/1463299. eCollection 2021.
To investigate the influence of cold weather on setup errors of patients with chest and pelvic disease in radiotherapy.
The image-guided data of the patients were collected from the Radiotherapy Center of Cancer Hospital Affiliated to Guangxi Medical University from October 2020 to February 2021. During this period, the cold weather days were December 15, 16, and 17, 2020, and January 7 and 8, 2021. For body fixation in radiotherapy, an integrated plate and a thermoplastic mold were employed in 18 patients with chest disease, while an integrated plate and a vacuum pad were applied in 19 patients with pelvic disease. All patients underwent cone beam computed tomography (CBCT) scans in the first five treatments and once a week thereafter. The obtained data were registered to the planning CT image to get the setup errors of the patient in the translational direction including , , and axes and rotational direction including , , and . Then, the Mann-Whitney test was performed. The expansion boundary values of the chest and pelvis were calculated according to the formula =2.5∑+0.7.
A total of 286 eligible results of CBCT scans were collected. There were 138 chest CBCT scans, including 26 taken in cold weather and 112 in usual weather, and 148 pelvic CBCT scans, including 33 taken in cold weather and 115 in usual weather. The -, -, and -axis translational setup errors of patients with chest disease in the cold weather group were 0.16 (0.06, 0.32) cm, 0.25 (0.17, 0.52) cm, and 0.35 (0.21, 0.47) cm, respectively, and those in the usual weather group were 0.14 (0.08, 0.29) cm, 0.23 (0.13, 0.37) cm, and 0.18 (0.1, 0.35) cm, respectively. The results indicated that there was a statistical difference in the -axis translational error between the cold weather group and the usual weather group ( = 935.5; =0.005 < 0.05), while there was no statistical difference in the rotational error between the two groups. The external boundary values of , , and axes in the cold weather group were 0.57 cm, 0.92 cm, and 0.99 cm, respectively, and those in the usual weather group were 0.57 cm, 0.78 cm, and 0.68 cm, respectively. There was no significant difference in the translational and rotational errors of patients with pelvic disease between the cold weather group and the usual weather group ( < 0.05). The external boundary values of , , and axes were 0.63 cm, 0.79 cm, and 0.68 cm in the cold weather group and 0.61 cm, 0.79 cm, and 0.61 cm in the usual weather group, respectively.
The setup error of patients undergoing radiotherapy with their bodies fixed by an integrated plate and a thermoplastic mold was greater in cold weather than in usual weather, especially in the ventrodorsal direction.
探讨天气寒冷对胸部和盆腔疾病放疗患者摆位误差的影响。
收集广西医科大学附属肿瘤医院放疗中心 2020 年 10 月至 2021 年 2 月间的患者图像引导数据。在此期间，2020 年 12 月 15、16、17 日和 2021 年 1 月 7、8 日为寒冷天气日。18 例胸部疾病患者采用一体化板和热塑模具进行体部固定，19 例盆腔疾病患者采用一体化板和真空垫。所有患者在最初五次治疗时均行锥形束 CT（CBCT）扫描，此后每周扫描一次。将获得的数据与计划 CT 图像进行配准，以获取患者在平移方向（包括 、 、 轴）和旋转方向（包括 、 、 轴）的摆位误差。然后，进行 Mann-Whitney U 检验。根据公式 =2.5∑+0.7，计算胸部和盆腔的扩展边界值。
共收集 286 例 CBCT 扫描结果。其中胸部 CBCT 扫描 138 例，寒冷天气组 26 例，常规天气组 112 例；盆腔 CBCT 扫描 148 例，寒冷天气组 33 例，常规天气组 115 例。寒冷天气组患者胸部疾病在 -、-、-轴方向的平移摆位误差分别为 0.16（0.06，0.32）cm、0.25（0.17，0.52）cm 和 0.35（0.21，0.47）cm，常规天气组分别为 0.14（0.08，0.29）cm、0.23（0.13，0.37）cm 和 0.18（0.1，0.35）cm，寒冷天气组在 -轴方向的平移误差与常规天气组比较，差异有统计学意义（ =935.5； =0.005<0.05），而两组间旋转误差比较，差异无统计学意义。寒冷天气组患者 、 、 轴的外扩边界值分别为 0.57cm、0.92cm 和 0.99cm，常规天气组分别为 0.57cm、0.78cm 和 0.68cm，两组患者在平移和旋转误差方面比较，差异无统计学意义（ <0.05）。寒冷天气组患者盆腔疾病在 、 、 轴方向的外扩边界值分别为 0.63cm、0.79cm 和 0.68cm，常规天气组分别为 0.61cm、0.79cm 和 0.61cm，两组间差异无统计学意义。
采用一体化板和热塑模具固定的胸部和盆腔疾病放疗患者在寒冷天气下的摆位误差大于常规天气，尤其是在腹背方向。
