Department of Speech and Hearing Sciences, University of Washington, Seattle, WA, USA
Department of Speech and Hearing Sciences, University of Washington, Seattle, WA, USA.
Trends Hear. 2015 Feb 4;19:2331216515569792. doi: 10.1177/2331216515569792.
A rapid threshold measurement procedure, based on Bekesy tracking, is proposed and evaluated for use with cochlear implants (CIs). Fifteen postlingually deafened adult CI users participated. Absolute thresholds for 200-ms trains of biphasic pulses were measured using the new tracking procedure and were compared with thresholds obtained with a traditional forced-choice adaptive procedure under both monopolar and quadrupolar stimulation. Virtual spectral sweeps across the electrode array were implemented in the tracking procedure via current steering, which divides the current between two adjacent electrodes and varies the proportion of current directed to each electrode. Overall, no systematic differences were found between threshold estimates with the new channel sweep procedure and estimates using the adaptive forced-choice procedure. Test-retest reliability for the thresholds from the sweep procedure was somewhat poorer than for thresholds from the forced-choice procedure. However, the new method was about 4 times faster for the same number of repetitions. Overall the reliability and speed of the new tracking procedure provides it with the potential to estimate thresholds in a clinical setting. Rapid methods for estimating thresholds could be of particular clinical importance in combination with focused stimulation techniques that result in larger threshold variations between electrodes.
提出并评估了一种基于 Bekesy 追踪的快速阈值测量程序，用于耳蜗植入物 (CI)。15 名后天失聪的成年 CI 用户参与了研究。使用新的跟踪程序测量了 200 毫秒双相脉冲序列的绝对阈值，并与在单极和四极刺激下使用传统的强制选择自适应程序获得的阈值进行了比较。在跟踪程序中，通过电流转向实现了跨越电极阵列的虚拟频谱扫描，该方法将电流分配到两个相邻电极之间，并改变每个电极的电流比例。总体而言，新的通道扫描程序和自适应强制选择程序的阈值估计之间没有发现系统差异。来自扫描程序的阈值的测试-重测可靠性比来自强制选择程序的阈值的可靠性稍差。然而，对于相同数量的重复，新方法的速度要快约 4 倍。总的来说，新的跟踪程序的可靠性和速度使其有可能在临床环境中估计阈值。在与导致电极之间阈值变化较大的聚焦刺激技术相结合的情况下，快速估计阈值的方法可能具有特别的临床重要性。
