目的　探讨不同度数鼻内镜(包括0°、30°、70°镜)在观察鼻咽癌放疗后鼻咽结构镜像的差异性，并分析各种镜头应用的优缺点。  方法　对我们2012年6月至2013年8月诊治的70例鼻咽癌患者放疗后进行定期随访，对应用不同度数鼻内镜观察查鼻咽结构的镜像临床资料进行研究、分析。  结果　鼻咽结构在不同度数鼻内镜下镜像存在差异，不同度数鼻内镜所观察的视野范围不同，鼻咽癌放疗后鼻咽结构观察效果存在差异，有统计学意义（P<0.05）。  结论    不同度数鼻内镜在观察鼻咽癌放疗后鼻咽结构存在差异性，各有优缺点，结果可供镜头选择的参考。

Objective　To explore the difference in the mirror image of nasopharyngeal structures observed using nasal endoscopy in various angles (0 °、30 °、 70 ° mirror) and to analyze  the advantages and disadvantages of the various lens application.　Methods　70 patients with nasopharyngeal carcinoma treated by radiotherapy and with regular follow-up from June, 2012 to August, 2013  in our department were involved. Clinical data about the mirror image of the nasopharyngeal structures observed using nasal endoscopy in various degrees were retrospectively analyzed.　Results　the mirror image of the nasopharyngeal structures observed using nasal endoscopy in various degrees were statistically different, and the visual fields of nasal endoscopy under various angles were statistically different (P<0.05) , with statistical significance (P<0.05).　Conclusions　Endoscopic imaging using nasal endoscopy with different angles in patients with nasopharyngeal carcinoma after radiotherapy can result in different mirror image,  which has its respective advantages and disadvantages. The outcomes of this study  can be used for reference for the selection of lens.