鼻咽癌放疗后颈淋巴结复发的影像学特征及临床意义

目的]探讨鼻咽癌放疗后颈淋巴结复发的影像学特征及临床意义。方法]分析2002～2008年在本院确诊为鼻咽癌放疗后颈淋巴结复发38例的影像学表现。结果]颈淋巴结复发以Ⅱ区最常见，约74%（28/38），多区复发约63%（24/38）。86%（25/29）为原部位复发。复发淋巴结以形态不规则且边缘不清楚及包膜外侵犯多见，在MRI-STIR序列上病变以中等及低信号多见。DWI以高低不等的混杂信号多见，实性区的平均ADC值为0.79×10^-3mm^2/s，坏死区为2.08×10^-3mm^2/s。结论]鼻咽癌放疗后颈淋巴结复发MRI表现不典型。结合MRI弥散加权成像（DWI）、PET/CT等多种影像检查技术有助于早期诊断。

Imaging Features of Cervical Lymph Node Recurrence follow-ing Radiotherapy in Nasopharyngeal Carcinoma and Their Clinical Significance

Purpose] To investigate the imaging features of cervical lymph node recurrence（CLNr） following radiotherapy for nasopharyngeal carcinoma（NPC）. Methods] The imaging features of CLNr in 38 cases with NPC following radiotherapy from 2002 to 2008 were analyzed. Results] Level Ⅱ was the most common site of CLNr, 74%（28/38）; muhiple levels 63%（24/38） and primary location 86%（25/29）. CLNr presented commonly as irregular shape, indistinct edge and penetrated capsule. CLN show moderate and/or low signal in MRI-STIR series. Mixtured signal with various value were very common in DWI, with an average ADC value 0.79×10^-3 mm^2/s in parenchymal region and 2.08×10^-3 mm^2/s in necrotic region. Conclusion] The MRI features of the CLNr in nasopharyngeal carcinoma following radiation are not typical and easily cause mis-diagnos. Combined multiple imagings with DWI and PET/CT et al are helpful for early diagnosis.