Zarowski A, Molisz A, Cardinael E, Vermeiren A, Theunen T, De Coninck L, Theuwis L, Siebert J, Offeciers F E
European Institute for ORL-HNS, AZ Sint-Augustinus Hospital, Antwerp, Belgium.
Department of Family Medicine, Medical University of Gdansk, Gdansk, Poland.
J Am Acad Audiol. 2020 Oct;31(9):674-679. doi: 10.1055/s-0040-1718701. Epub 2021 Feb 8.
Fitting cochlear implants in babies and noncooperative patients is cumbersome and time consuming. Therefore, objective parameters have been sought in order to predict the subjective threshold (T) and maximum comfort (C) levels. Measurements of the electrically evoked compound action potentials (ECAPs) have been widely used for this purpose, yet the correlation between these objective measures and the subjective T/C levels is weak to moderate.
This article aims (1) to evaluate correlations between the subjective parameters of the fitting maps such as thresholds (T level) and maximum comfort levels (C level), the impedance of the electrode contacts, and the ECAP thresholds, and (2) to compare the value of the electrode impedances and the ECAP measures for prediction of the T/C levels.
Case review study in a quaternary otologic referral center.
Ninety-eight consecutive CI patients were enrolled. The average age of the patients was 49 years. All patients were users of the Nucleus 24RECA (Freedom, Contour Advance-of-Stylet electrode) cochlear implant.
Data on impedance of the electrode contacts and the behavioral T/C levels at the first fitting session (2-5 weeks after surgery) and at the 5th fitting session (4-6 months after surgery) have been retrospectively collected in 98 consecutive CI patients. Additionally, the intraoperative impedance values and the ECAP thresholds (tNRT) have been recorded.
Impedances of electrode contacts show significant strong negative correlations with the stabilized T/C levels at 4 to 6 months after implantation and are an important predictor for the behavioral T/C levels. They can explain = 28 to 41% of the variability of the behavioral T/C levels. In multiple regression analysis electrode contact impedances can explain twice as much of the variability of the stabilized T/C levels than the tNRT values. The electrode impedances together with the tNRT values are able to explain = 37 to 40% of the global variability of the T/C levels while the tNRT thresholds solely are able to explain only = 5 to 14% of the T/C levels variability.
Impedances of electrode contacts correlate strongly with the stabilized behavioral T/C levels and may be used as an objective measure for fitting of cochlear implants.
给婴儿和不配合的患者植入人工耳蜗既麻烦又耗时。因此，人们一直在寻找客观参数，以预测主观阈值（T）和最大舒适度（C）水平。为此，电诱发复合动作电位（ECAP）测量已被广泛应用，但这些客观测量与主观T/C水平之间的相关性较弱至中等。
本文旨在（1）评估配适图的主观参数（如阈值（T水平）和最大舒适度水平（C水平））、电极触点阻抗和ECAP阈值之间的相关性，以及（2）比较电极阻抗和ECAP测量值对T/C水平预测的价值。
在一家四级耳科转诊中心进行病例回顾研究。
连续纳入98例人工耳蜗植入患者。患者的平均年龄为49岁。所有患者均使用Nucleus 24RECA（自由型、轮廓推进式电极人工耳蜗）。
回顾性收集了98例连续人工耳蜗植入患者首次配适时（术后2 - 5周）和第5次配适时（术后4 - 6个月）电极触点阻抗和行为T/C水平的数据。此外，还记录了术中阻抗值和ECAP阈值（tNRT）。
电极触点阻抗与植入后4至6个月稳定的T/C水平呈显著强负相关，是行为T/C水平的重要预测指标。它们可以解释行为T/C水平变异性的28%至41%。在多元回归分析中，电极触点阻抗对稳定T/C水平变异性的解释能力是tNRT值的两倍。电极阻抗与tNRT值共同能够解释T/C水平总体变异性的37%至40%，而单独的tNRT阈值仅能解释T/C水平变异性的5%至14%。
电极触点阻抗与稳定的行为T/C水平密切相关，可作为人工耳蜗植入配适的客观指标。
