REZ-1人工耳蜗电极植入方法的改进研究

A new method for REZ-1 cochlear implant electrode array insertion

目的探讨使REZ-1人工耳蜗电极靠近蜗轴的植入方法。方法22例尸头标本CT扫描测量耳蜗直径后，植入REZ-1人工耳蜗电极，完成植入后回撤1～2个电极环，耳蜗位摄片，测量蜗轴与电极环之间距离是否有所改变。测量60例CT扫描显示一侧中耳、内耳结构正常病例的耳蜗直径。结果22例标本中3例植入27个电极环，19例植入28个电极环。回撤电极后，与回撤前相比17例标本中第12至第19个电极环与蜗轴的距离减小（配对t检验，P〈0．01），该17例标本的耳蜗直径均小于9．50mm；而耳蜗直径大于9．60mm的5例标本均没有出现电极环靠近蜗轴的改变。17例电极回撤后靠近蜗轴的标本耳蜗直径为9．11（0．57）mm[中位数（四分位数间距），下同]，另外5例标本耳蜗直径为9．78（0．28）mm，二者差异具有统计学意义（Mann-Whitney秩和检验，P〈0．001）。60例正常耳蜗直径（x±s）为（9．04±0．45）mm，90％小于9．50mm。结论REZ-1人工耳蜗电极植入后回撤电极的植入方法可以使耳蜗直径小于9．50mm的患者底回内部分电极环靠近蜗轴。术前CT扫描测量耳蜗直径可以为REZ-1人工耳蜗电极选择植入方法提供帮助。

Objective To develop a new method for REZ-1 cochlear implant electrode array insertion. Methods REZ-1 cochlear implant electrode array was implanted in 22 human temporal bone specimens. Cochlear diameters were measured from spiral CT scan before implantation. Cochlear views were taken before and after pullback technique. Modiolus-electrode distances were measured and compared. The diameters of sixty normal cochleae were measured. Results In 3 cases, 27 electrode rings were inserted into the cochlea, while in others, all 28 electrode rings were inserted into the cochlea. After pullback of the electrode array, No. 12 to No. 19 electrode rings were closer to the modiolus in 17 cases （paired t test, P 〈 0. 01 ）. The cochlear diameters in the 17 cases were smaller than 9. 50 mm, while in the other 5 cases, the cochlear diameters were at least 9. 60 mm. The cochlear diameters in the 17 cases were 9.11 （0. 57 ） mm, while the cochlear diameters in the 5 cases were 9.78（0. 28） mm（ Mann-Whitney test, P 〈0. 001 ）. The diameters of normal cochleae were （9.04±0.45 ） ram, with 90% larger than 9.50 mm. Conclusions In cases whose cochlear diameter is smaller than 9. 50 mm, pullback technique can help some electrode rings be closer to the modiolus. Measurement of the cochlear diameter can help the surgeon to have a better choice in the selection of REZ-1 cochlear implantation methods.