床面高度作为摆位参数对放射治疗精确度的影响

Impact of Bed Height as Setup Parameter on Accuracy of Radiation Therapy

目的:探究在放射治疗患者中通过床面高度行垂直摆位参数的实际临床意义。方法:截取某院2010年3月至2012年1月共68例通过予真空袋固定的体部肿瘤患者,利用EPID拍摄系统以首次摆位侧位片为标准,在放疗末段以床高、源皮距为参数行摆位及拍摄侧位片,测量图像中心点垂直位移情况。结果:源皮距组:>3 mm的中心点偏差共26例,精确度为62.61%;床高组:>3 mm中心点偏差共12例,精确度为82.35%,床高组精确度比源皮距组高出19.74个百分点,进行统计分析,P<0.05,差异具有统计学意义。结论:在胸腹部放疗患者中如将床面高度定位垂直方向摆位参数,可以减少治疗中心移位误差性,提高精准摆位,提升精确治疗质量,保证患者生命安全。

Objootive To explore the actual clinical significance of bed height as setup parameter on the radiation therapy patients. Mothods Sixty-eight cases of patients with body tumors fixed to the vacuum bag in the Affiliated Cancer Hospital of Tianjin Medical University from March 2010 to January 2012 were selected, and EPID shooting system was used with the first position of lateral radiographs as the standard. Bed height and source-skin distance were adopted as the parameters to perform setup and lateral radiography and measurement of the vertical displacement of the image center. Results In the group of source-skin distance, there were 26 ones whose centers had a displacement more than 3 mm, with an accuracy of 62.61%, and in the group of bed height, there were 12 ones whose centers had a displacement more than 3 mm, with an accuracy of 82.35%. Irs significantly different between the two groups with P less than 0.05. Conclusion To set the bed height as the posture parameter in the vertical direction can decrease the error of center displacement and increase the precision of setup, and then the therapy quality can be enhanced and the patient safety be ensured.