Blasco Michael A, Redleaf Miriam I
*College of Medicine, University of Illinois at Chicago, Chicago, Illinois, and †Director of Otology/Neurotology, Department of Otolaryngology-Head and Neck Surgery, University of Illinois Hospitals and Health Sciences System-Chicago, Chicago, Illinois, U.S.A.
Otol Neurotol. 2014 Sep;35(8):1426-32. doi: 10.1097/MAO.0000000000000431.
In recent years, otologists have begun to place cochlear implants into nonfunctioning ears after sudden unilateral hearing loss. Patients in these trials demonstrate differing degrees of hearing loss in the unimplanted ear. Few studies have examined the role of implantation in patients with normal hearing in the unimplanted ear. To understand if this practice benefits these patients in terms of tinnitus, sound localization, and speech understanding, the available world literature is reviewed.
MEDLINE, Embase, and Cochrane databases were searched for publications from database inception to June 1, 2013, without restriction of language.
A search of multiple medical databases was performed to identify articles reporting cases series of cochlear implantation for unilateral hearing loss. Subjects were included for analysis only if the course of hearing loss was acute and rapidly progressive, if the loss was severe to profound, and if the contralateral ear had normal hearing.
Nine appropriate articles were identified, in which 36 patients met our inclusion criteria. Three meta-analyses were performed: of tinnitus (22 patients); of the lowest signal-to-noise ratio, which still allowed 50% sentence understanding (16 patients); and of sentence understanding at a fixed signal-to-noise ratio (12 patients). These found that measures of tinnitus reduction and decreased signal-to-noise ratios to still allow 50% speech discrimination were statistically significantly reduced. Systematic review of subjective changes of tinnitus in 27 patients, speech understanding in 16 patients, and sound localization in 16 patients found 96%, 100%, and 87% were improved, respectively.
Cochlear implantation in unilateral sudden hearing loss with a normal functioning contralateral ear might prove to be an effective therapy. Tinnitus is reduced as is the signal-to-noise ratio, which still allows 50% speech discrimination. All patients felt that they localized sound better, and most felt that they understood speech better. Further studies should be conducted to compare the success of hearing rehabilitation of cochlear rehabilitation and traditional modalities such as contralateral routing of signal and bone-anchored hearing aids.
近年来，耳科医生已开始在单侧突发听力损失后将人工耳蜗植入无功能的耳朵。这些试验中的患者在未植入人工耳蜗的耳朵中表现出不同程度的听力损失。很少有研究探讨在未植入人工耳蜗的耳朵听力正常的患者中进行植入的作用。为了解这种做法在耳鸣、声音定位和言语理解方面是否对这些患者有益，我们对现有的世界文献进行了综述。
检索MEDLINE、Embase和Cochrane数据库，查找从数据库建立至2013年6月1日的出版物，不限语言。
检索多个医学数据库，以识别报道单侧听力损失人工耳蜗植入病例系列的文章。仅当听力损失病程为急性且快速进展、损失为重度至极重度，且对侧耳朵听力正常时，才纳入受试者进行分析。
识别出9篇合适的文章，其中36例患者符合我们的纳入标准。进行了三项荟萃分析：耳鸣（22例患者）；仍能实现50%句子理解的最低信噪比（16例患者）；以及固定信噪比下的句子理解（12例患者）。这些分析发现，耳鸣减轻以及使信噪比降低到仍能实现50%言语辨别力的程度在统计学上有显著降低。对27例患者耳鸣主观变化、16例患者言语理解和16例患者声音定位的系统评价发现，改善率分别为96%、100%和87%。
对侧耳朵功能正常的单侧突发听力损失患者进行人工耳蜗植入可能是一种有效的治疗方法。耳鸣减轻，使信噪比降低到仍能实现50%言语辨别力的程度。所有患者都感觉声音定位更好，大多数患者感觉言语理解更好。应进行进一步研究，以比较人工耳蜗康复与传统模式（如对侧信号路由和骨锚式助听器）听力康复的成功率。
