摘要
目的探讨CTVision系统在分析鼻咽癌放疗过程靶区体积及其剂量学变化规律中的应用价值。方法采用CTVision系统对10例鼻咽癌患者进行图像引导调强放疗,分析鼻咽癌靶区及腮腺体积在放疗过程中的变化规律。并将采集到的CT图像传回计划系统,重新计算并分析危险器官的剂量。结果靶区及双侧腮腺体积随放疗过程的进展呈现逐渐递减的规律,其中靶区体积和右侧腮腺体积在放疗第4周时与放疗前有明显差异,左侧腮腺体积在放疗第5周时与放疗前有明显差异;且左右侧腮腺所受到的照射剂量随体积缩小而逐渐增加,并与体积缩小程度呈正相关（右侧腮腺r=0.471,P=0.036;左侧腮腺r=0.578,P=0.008）。结论鼻咽癌患者在调强放疗过程中,靶区及腮腺体积会随着放疗进程而逐渐缩小,并导致腮腺受照射剂量增加,故建议在调强放疗的第4~5周重新勾画靶区及危险器官并重新制定放疗计划,以提高鼻咽癌局控率并减少放疗副反应。
Objective To study the effectiveness of application of CTVision system in analysis of the change law of the target volume and dose for nasopharyngeal carcinoma in the course of radiotherapy.Methods Image-guided IMRT（Intensity-Modulated Radiation Therapy） was performed in 10 patients with nasopharyngeal carcinoma by using CTVision system to analyze the change law of the volume of target area and parotids.Then,the CT images were transmitted back to the TPS（Treatment Planning System） for recalculation and analysis of the dose for organs at risk.Results The volume of target area as well as the volume of bilateral parotids was diminishing with the progress of radiotherapy.And the volume of target area as well as the volume of right-sided parotids revealed obvious differences in the 4th week of radiotherapy from the pre-treatment volume.The volume of left-sided parotids revealed obvious differences in the 5th week of radiotherapy from the pre-treatment volume.Meanwhile,the radiation dose received by bilateral parotids increased gradually with the shrinkage of the volume,and was positively associated with the shrinkage degree（Right-sided parotids：r=0.471,P=0.036; Left-sided parotids：r=0.578,P=0.008）.Conclusion For nasopharyngeal carcinoma patients who were experiencing IMRT,the volume of target area and parotids was shrinking with the progress of radiotherapy,leading to the increasing of the dose for organs.In view of this,it was suggested to redraw the outline of the target area and redesign the radiotherapy plan in the 4th to 5th week in of IMRT,which would improve the local control rate of nasopharyngeal carcinoma and reduce the side effects of radiation.
出处
《中国医疗设备》
2015年第11期35-38,46,共5页
China Medical Devices
基金
广西自然科学基金(2012GXNSFAA053166)
关键词
CTVision系统
图像引导
鼻咽癌
调强放疗
CTVision system
image-guided
nasopharyngeal carcinoma
intensity-modulated radiation therapy
