Department Otorhinolaryngology, Utrecht Department of Otorhinolaryngology, Head and Neck Surgery, University Medical Center Utrecht, Utrecht, the Netherlands.
Department of Otorhinolaryngology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Centre Nijmegen, Nijmegen, the Netherlands.
Trends Hear. 2024 Jan-Dec;28:23312165241264466. doi: 10.1177/23312165241264466.
This study investigated sound localization abilities in patients with bilateral conductive and/or mixed hearing loss (BCHL) when listening with either one or two middle ear implants (MEIs). Sound localization was measured by asking patients to point as quickly and accurately as possible with a head-mounted LED in the perceived sound direction. Loudspeakers, positioned around the listener within a range of +73°/-73° in the horizontal plane, were not visible to the patients. Broadband (500 Hz-20 kHz) noise bursts (150 ms), roved over a 20-dB range in 10 dB steps was presented. MEIs stimulate the ipsilateral cochlea only and therefore the localization response was not affected by crosstalk. Sound localization was better with bilateral MEIs compared with the unilateral left and unilateral right conditions. Good sound localization performance was found in the bilaterally aided hearing condition in four patients. In two patients, localization abilities equaled normal hearing performance. Interestingly, in the unaided condition, when both devices were turned off, subjects could still localize the stimuli presented at the highest sound level. Comparison with data of patients implanted bilaterally with bone-conduction devices, demonstrated that localization abilities with MEIs were superior. The measurements demonstrate that patients with BCHL, using remnant binaural cues in the unaided condition, are able to process binaural cues when listening with bilateral MEIs. We conclude that implantation with two MEIs, each stimulating only the ipsilateral cochlea, without crosstalk to the contralateral cochlea, can result in good sound localization abilities, and that this topic needs further investigation.
本研究调查了双侧传导性和/或混合性听力损失（BCHL）患者在使用一个或两个中耳植入物（MEI）时的声音定位能力。通过要求患者用头戴式 LED 尽可能快速和准确地指向感知声音的方向，来测量声音定位。扬声器位于听众周围，在水平平面内的+73°/-73°范围内，患者无法看到扬声器。宽带（500 Hz-20 kHz）噪声突发（150 ms），以 10 dB 为步长在 20 dB 范围内波动。MEI 仅刺激同侧耳蜗，因此定位响应不受串扰影响。与单侧左和单侧右条件相比，双侧 MEI 可实现更好的声音定位。在双侧辅助听力条件下，四名患者的声音定位性能良好。在两名患者中，定位能力等同于正常听力表现。有趣的是，在未辅助条件下，当两个设备都关闭时，受试者仍然可以定位在最高声音水平呈现的刺激。与双侧骨导设备植入患者的数据进行比较表明，MEI 的定位能力更优。这些测量结果表明，使用未辅助条件下残余的双耳线索的双侧传导性和/或混合性听力损失患者，在使用双侧 MEI 聆听时能够处理双耳线索。我们得出结论，植入两个 MEI，每个 MEI 仅刺激同侧耳蜗，而不会对侧耳蜗产生串扰，可以实现良好的声音定位能力，并且这个问题需要进一步研究。
