[Prediction of round window visibility in cochlear implantation with temporal bone high resolution computed tomography].

Objective: To discuss the prediction of round window(RW) visibility in cochlear implantation(CI) with temporal bone high resolution computed tomography(HRCT). Methods: From January 2013 to January 2017, 130 cases underwent both HRCT and CI in our hospital were analyzed. The distance from facial nerve to posterior canal wall(FWD), the angle between facial nerve and inner margin of round window(FRA), and the angle between facial nerve and tympanic anulus to inner margin of round window(FRAA) were detected at the level of round window on axial temporal bone HRCT. A line parallel to the posterior wall of ear canal was drawn from the anterior wall of facial nerve at the level of round window on axial temporal bone HRCT and its relationship with round window was detected (facial-round window line, FRL): type0-posterior to the round window, type1-between the round window, type2-anterior to the round window. Their(FWD, FRA, FRAA, FRL) relationships with intra-operative round window visibility were analyzed by SPSS 17.0 software. Results: FWD(F=18.76, P=0.00), FRA(F=34.57, P=0.00), FRAA (F=14.24, P=0.00) could affect the intra-operative RW visibility significantly. RW could be exposed completely during CI when preoperative HRCT showing type0 FRL. RW might be partly exposed and not exposed when preoperative HRCT showing type1 and type2 FRL respectively. Conclusion: FWD, FRA, FRAA and FRL of temporal bone HRCT can predict intra-operative round window visibility effectively in CI surgery.目的： 探讨颞骨高分辨率CT(high resolution computed tomography, HRCT)对人工耳蜗植入(cochlear implantation，CI)术中圆窗暴露难易程度的预判方法。 方法： 分析2013年1月至2017年1月在郑州大学第一附属医院行颞骨HRCT检查并行CI手术的130例患者的临床资料，统计其轴位HRCT圆窗层面上：①面神经垂直段外缘至外耳道后壁内缘的垂直距离(面－壁距)；②面神经与圆窗内后缘在耳蜗底壁的夹角(面－窗角)；③面神经与鼓环在圆窗内后缘的夹角(面－窗－环角)的数值。经面神经外缘做一与外耳道后壁平行的直线(面－窗线)，按其是否穿过圆窗进行分类：0型，面－窗线位于圆窗后方；1型，面－窗线与圆窗相交；2型，面－窗线位于圆窗前方。分别将上述参数与CI术中圆窗暴露难易程度进行比较分析，统计学处理采用SPSS17.0软件。 结果： 面－壁距、面－窗角、面－窗－环角对术中圆窗暴露难易程度的影响均有统计学意义(F值分别为18.76、34.57和14.24，P值均<0.05)。0型面－窗线，圆窗易暴露；1型面－窗线，圆窗部分暴露的可能性大；2型面－窗线，圆窗无法暴露的可能性大。 结论： 术前颞骨HRCT能够很好地预判CI术中圆窗暴露的难易程度，面－壁距、面－窗角、面－窗－环角都可作为判断指标，而面－窗线相对简便有效。.