语前聋儿童人工耳蜗植入后的调机与声场评估

目的 调查语前聋儿童人工耳蜗植入术后声场主观测听阈值和对应T值的变化趋势。方法 28例人工耳蜗植入儿童。年龄3—6岁。无耳蜗畸形，植入后电极阻抗测试完全正常。对开机后3月、6月和1年时间的声场主观测听阈值与T值的变化进行了统计分析。结果 声场测听阈值在开机1年中呈逐渐降低趋势，开机1年时声场测听的听力水平较3个月和6个月有明显提高（P〈0．05）。植入者术后一年声场主观测听（啭音）听阈为15—35dB HL，听力水平较术前有明显提高。28例植入者T值在开机一年后明显低于六个月和三个月的水平（P〈0．05）。结论 开机后一年内T值和声场测听阈值都呈逐渐下降趋势．并且与3个月和6个月的水平差异具有统计学意义。植入者在熟悉适应了电声信号后，可以在刺激电流强度下降的同时获得更好的听力。

Evaluation of subjective auditory threshold in sound field after cochlear implantation

Objective To investigate the changes of subjective auditory threshold and T-level after cochlear implantation in prelingual deafness children. Methods Twenty-eight children(between 3-6 years) received a cochlear implant. Electrode impedance test after implantation were all normal. Subjective auditory threshold and T-level mapping were tested at 3 months,6 months and 1 year after implantation. Results Subjective auditory thresholds decreased gradually in the first year after cochlear implantation. It was between 15-35 dB HL at 1 year,significantly better than at 3 months and 6 months (P < 0.05). T-level at 1 year was much lower than that at 3 months and 6 months(P < 0.05). Conclusion T-level and subjective auditory threshold tapered significantly at 1 year after cochlear implantation compared with that at 3 months and 6 months. It suggested that patients could get better hearing performance when familiar with electric sound signal,meanwhile electric stimulation diminished.