鼻咽癌放射治疗对中耳功能影响的临床研究

A Clinical Study of the Effect of Radiotherapy for Nasopharyngeal Carcinoma on the Function of Middle Ear

目的:探讨鼻咽癌(NPC)放射治疗导致中耳功能影响的程度、类型,以及NPC放疗并发分泌性中耳炎(SOM)中耳功能变化特点。方法:选择全程放疗、有完整资料的NPC患者57例。分别采用先常规放疗+3DCRT加量和直接三维适形放疗(3DCRT)两种放疗方式,利用226Hz、1000Hz不同探测音鼓室图及多频鼓室图、纯音听阈检测、耳声发射对比研究NPC放疗前、后中耳功能情况。结果:57例患者中SOM发生率为19%(22耳/114耳),在放疗后期及放疗后半年内容易发生;在NPC放射治疗早期多频鼓室图中耳共振频率增加;Y226Hz"C"或"B"型鼓室图、共振频率低于500Hz,中耳积液可能性大。31例采用直线加速器先常规放疗+3DCRT方式放疗,并发SOM率为22.58%(14/62耳);采用3DCRT方式直接放射治疗26例,并发率为15.38%(8/52耳),二者差异具有统计学意义(P<0.05),但发生SOM的时间上无明显差异。结论:NPC放疗导致SOM等中耳功能障碍发生率较高,利用多频鼓室图在NPC放疗致中耳功能障碍的诊断中具有重要的意义。

Objective ： To investigate the effect of radiotherapy for nasopharyngeal carcinoma on the function of middle ear including the degree, type as well as the characteristics of secretory otitis media （SOM） occurred during the course of radiotherapy. Methods： 57 cases of patients with complete data and receiving the whole procedure of radiotherapy were enrolled in this study. The following two methods were applied to the radiation treatment of nasopharyngeal carcinoma, the general radiotherapy plus three-dimen- sional conformal radiation（3-DCRT） and direct 3-DCRT. We studied the middle ear function of the patients before and after radiotherapy by the measures of 226Hz, 1000Hz probe tone multi-frequency tympanometry, tympanometry , pure tone threshold testing and otoacoustic emission measures. Results： SOM inclined to occure during radiotherapy and six months after radiotherapy, and the rate was 19% （22 ears / 114 ears）. The middle ear resonance frequency increased in the early period of radiotherapy. When the Y-226Hz tympanogram was ＂ C＂ or ＂B＂ type , and the middle ear resonance frequency lower than 500Hz, the possibility of middle ear effusion increased. For the 31 patients who were treated by the conventional linear accelerator radiotherapy followed by 3DCRT ,the incidence of SOM was 22.58% （ 14/62 ears） while for the 26 patients who accepted the direct 3-DCRT radiotherapy, the incidence was 15.38% （ 8 / 52 ears）. The difference was significant （ P 〈 0.05）. However, there was no significant difference for the occuring time of SOM. Conclusion： The incidence of radiotherapy induced middle ear dysfunction including SOM for NPC patients is high. It is of great significance to diagnose middle ear dysfunction induced by radiotherapy of NPC by the multi-frequency tympanometry testing.