螺旋断层放疗系统自适应软件在评价腮腺剂量变化中的初步应用

介绍了研究螺旋断层放疗（Helical tomotherapy,HT）系统自适应软件系统在评价头颈部癌腮腺剂量学变化中的应用价值。该自适应软件以HT系统为平台,通过MVCT扫描得到的影像,计算感兴趣区域实际体积及照射剂量,并以此为基础决定是否进行重新改野以及改野的时机,为实现自适应放疗提供帮助。本研究以一例鼻咽癌为样本,评价双侧腮腺在整个放疗过程中的体积及剂量学变化。在每周及最后一次行MVCT扫描,共8次图像系列。随着治疗疗程的进行,腮腺体积逐渐缩小,接受剂量逐渐增加,腮腺体积变化和V1与D50呈负性相关（p均〈0.05）。

Assessment of Parotid Gland Dose Variations by Helical Tomotherapy Adaptive System in Head and Neck Cancer

The paper introduces a helical tomotherapy （HT） adaptive system in assessment of parotid gland dose variation in head and neck cancer. The system,which helical therapy unit is equipped with,is based on megavoltage computed tomography （MVCT） images to calculate the actual volume and dose of region of interest （ROI）. Whether to change plan is judged on the fact for the realization of adaptive radiotherapy. One case of nasopharyngeal carcinoma was as a sample to evaluate parotid gland dose variation during the treatment. On every week and last time,patient was scanned by MVCT before treatment,a total of eight MVCT images. As the treatment progressed,the parotid gland volume was shrinking and the dose was increasing. The parotids volume variation was negatively related with D50 and V1 （both P 0.05）.