Yorkshire Auditory Implant Service, Bradford Royal Infirmary, Bradford, United Kingdom.
School of Allied Health Professions and Sport, University of Bradford, Bradford, United Kingdom.
Ear Hear. 2019 Jul/Aug;40(4):870-877. doi: 10.1097/AUD.0000000000000666.
The study aimed to determine the effect of interimplant interval and onset of profound deafness on sound localization in children with bilateral cochlear implants, controlling for cochlear implant manufacturer, age, and time since second implant.
The authors conducted a retrospective, observational study using routinely collected clinical data. Participants were 127 bilaterally implanted children aged 4 years or older, tested at least 12 mo post- second implant. Children used implants made by one of three manufacturers. Sixty-five children were simultaneously implanted, of whom 43% were congenitally, bilaterally profoundly deaf at 2 and 4 kHz and 57% had acquired or progressive hearing loss. Sixty-two were implanted sequentially (median interimplant interval = 58 mo, range 3-143 mo) of whom 77% had congenital and 23% acquired or progressive bilateral profound deafness at 2 and 4 kHz. Children participated in a sound-source localization test with stimuli presented in a random order from five loudspeakers at -60, -30, 0, +30, and +60 degrees azimuth. Stimuli were prerecorded female voices at randomly roved levels from 65 to 75 dB(A). Root mean square (RMS) errors were calculated. Localization data were analyzed via multivariable linear regression models, one applied to the whole group and the other to just the simultaneously implanted children.
Mean RMS error was 25.4 degrees (SD = 12.5 degrees) with results ranging from perfect accuracy to chance level (0-62.7 degrees RMS error). Compared with simultaneous implantation, an interimplant interval was associated with worse localization by 1.7 degrees RMS error per year (p < 0.001). Compared with congenital deafness, each year with hearing thresholds better than 90 dB HL at 2 and 4 kHz bilaterally before implantation led to more accurate localization by 1.3 degrees RMS error (p < 0.005). Every year post-second implant led to better accuracy by 1.6 degrees RMS error (p < 0.05). Med-El was associated with more accurate localization than Cochlear by 5.8 degrees RMS error (p < 0.01) and with more accurate localization than Advanced Bionics by 9.2 degrees RMS error (p < 0.05).
Interimplant interval and congenital profound hearing loss both led to worse accuracy in sound-source localization for children using bilateral cochlear implants. Interimplant delay should therefore be minimized for children with bilateral profound hearing loss. Children presenting with acquired or progressive hearing loss can be expected to localize better via bilateral cochlear implants than their congenitally deaf peers.
本研究旨在探讨植入间隔时间和先天性重度耳聋对双侧人工耳蜗植入儿童声音定位的影响，同时控制耳蜗植入物制造商、年龄和第二次植入后时间的影响。
作者进行了一项回顾性、观察性研究，使用常规收集的临床数据。参与者为 127 名 4 岁及以上双侧植入人工耳蜗的儿童，至少在第二次植入后 12 个月接受测试。儿童使用三家制造商之一生产的植入物。65 名儿童同时植入，其中 43%在 2 和 4 kHz 处双侧先天性、重度耳聋，57%有获得性或进行性听力损失。62 名儿童依次植入（中位植入间隔=58 个月，范围 3-143 个月），其中 77%在 2 和 4 kHz 处双侧先天性、重度耳聋，23%有获得性或进行性双侧重度耳聋。儿童在 5 个扬声器处从 -60、-30、0、+30 和+60 度方位以随机顺序接受声源定位测试。刺激物是从 65 到 75 dB(A)的随机漫游水平的女性预先录制的声音。计算均方根（RMS）误差。通过多变量线性回归模型分析定位数据，一个模型应用于整个组，另一个模型仅应用于同时植入的儿童。
平均 RMS 误差为 25.4 度（标准差=12.5 度），结果从完全准确到机会水平（0-62.7 度 RMS 误差）不等。与同时植入相比，植入间隔每年增加 1.7 度 RMS 误差（p<0.001）。与先天性耳聋相比，在植入前双侧 2 和 4 kHz 的听力阈值每改善 10 分贝（HL），定位精度就会提高 1.3 度 RMS 误差（p<0.005）。第二次植入后每年都会提高 1.6 度 RMS 误差（p<0.05）。与 Cochlear 相比，Med-El 更准确，平均 RMS 误差为 5.8 度（p<0.01），与 Advanced Bionics 相比，平均 RMS 误差为 9.2 度（p<0.05）。
植入间隔时间和先天性重度听力损失都会导致双侧人工耳蜗植入儿童声源定位的准确性下降。因此，对于双侧重度听力损失的儿童，应尽量减少植入间隔时间。与先天性耳聋的同龄人相比，患有获得性或进行性听力损失的儿童可以通过双侧人工耳蜗植入获得更好的定位效果。
