[目的]探讨腮腺分区勾画对伴有双颈部Ⅱ区淋巴结转移鼻咽癌调强放射治疗计划优化的影响。[方法]选择接受调强放疗的双颈部Ⅱ区淋巴结转移的鼻咽癌患者20例,利用Corvus 6.3调强治疗计划系统设计3种治疗计划:既未进行腮腺分区勾画的常规计划(Plan0);将腮腺沿下颌后静脉前外缘作与腮腺后界的平行线,将腮腺分成前外与后内两部分,分别予剂量限制,重新计划优化,得到将腮腺分区勾画的计划(Plan1);将腮腺分区勾画的CT序列定义为模体,由常规计划(Plan0)进行正向运算得到计划2(Plan2)。比较Plan1与Plan2在靶区和正常组织的剂量分布。[结果]两套计划均符合RTOG0615靶区及正常组织剂量限制要求。采用该腮腺分区勾画方法能够降低整个腺体的平均辐射剂量、V15以及<20Gy体积,这主要归功于降低了腮腺前外侧区约20%的平均辐射剂量、30%~40%的V15。[结论]在伴有双颈部Ⅱ区淋巴结转移鼻咽癌IMRT中,腮腺分区勾画在理论上和剂量学上具有可行性,尤其降低了干细胞集中部位(腮腺前外侧区)的辐射剂量,具有一定推广应用价值,对腮腺分泌功能的影响有待前瞻性随机试验证实。 [Objective] To explore the effect of parotid gland mapping on the optimization of intensity-modulated radiation therapy planning for patients with lymph node metastasis in two-neck region Ⅱ. [Methods] Twenty patients with nasopharyngeal carcinoma who underwent double-neck radiotherapy for metastatic cervical lymph node metastasis undergoing intensity modulated radiotherapy were enrolled in this study. Three kinds of treatment plans were designed using Corvus 6.3 intensity-modulated treatment planning system: Plan 0, ; The parotid gland along the anterior margin of the posterior mandibular vein with the parotid gland posterior parallel line, the parotid gland divided into anteroposterior and posterior two fractions, respectively, to dose limits, re-planning and optimization, parotid glancing plan (Plan1); The CT sequence delineated by the parotid gland division is defined as the motif, and the plan 2 (Plan2) is obtained through the forward operation from the normal plan (Plan0). The dose distribution of Plan1 and Plan2 in the target area and normal tissue was compared. [Results] Both plans met the RTOG0615 target area and normal tissue dose limits. This parotid subdivision outlined reduces average radiation doses throughout the gland, V15 and <20 Gy, largely due to a reduction of approximately 20% of the mean radiation dose in the parotid anterolateral region and 30% -40% of V15. [Conclusion] The parotid gland division mapping is feasible theoretically and dose-wise in IMRT associated with lymph node metastasis of two-neck region II, especially reducing the dose of stem cell concentration (parotid anterolateral region) with the dose of A certain value of promoting the application of parotid secretory function to be prospective randomized trials confirmed.