Guan Ruirui, Wang Yanqi, Wu Sasa, Zhang Bo, Sun Jingwu, Guo Xiaotao, Sun Jiaqiang
Department of Otolaryngology Head and Neck Surgery, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, China.
Front Neurol. 2021 Apr 29;12:675502. doi: 10.3389/fneur.2021.675502. eCollection 2021.
Cochlear implantation (CI) helps patients with severe or profound sensorineural hearing loss (SNHL) restore hearing and speech abilities. However, some patients exhibit abnormal vestibular functions with symptoms such as dizziness or balance disorders, after CI. Whether age at CI and CI approach (unilateral or sequential bilateral) affect vestibular functions in users with cochlear implants remains unclear. To investigate the vestibular functions in children and adults before and after unilateral or sequential bilateral CI. Thirty-seven patients with severe or profound SNHL who were candidates for a first- or second-side CI were divided into three groups: first-side CI-implanted adults (≥18 years), first-side CI-implanted children (6-17 years), and second-side CI-implanted children (6-17 years). All cases were implanted with the round window approach to minimize damage to the intra-cochlear structures. The caloric test, vestibular evoked myogenic potential (VEMP) test, video head impulse test (vHIT), Dizziness Handicap Inventory (DHI), Pediatric Vestibular Symptom Questionnaire (PVSQ), and audiometric tests were performed before and 1 month after CI. The abnormal rates of caloric test and VEMP test after CI in the first-side CI-implanted adults and children significantly increased compared with those before CI. The pre-implantation VEMP test showed significantly higher abnormal rates between first- and second-side CI-implanted children. No other significant differences of abnormal rates between first- and second-side CI-implanted children or between first-side CI-implanted adults and children were found. In second-side CI-implanted children, PVSQ scores significantly increased at day 3 post-implantation but decreased at day 30. CI has a negative effect on the results of caloric and VEMP tests, but not on vHIT, indicating that the otolith and low-frequency semicircular canal (SCC) are more vulnerable to damage from CI. The alterations of vestibular functions resulting from CI surgery may be independent of age at CI and CI approach (unilateral or sequential bilateral). Long-term impacts on the vestibular function from CI surgery, as well as the chronic electrical stimulation to the cochlea, are still to be investigated.
人工耳蜗植入（CI）可帮助重度或极重度感音神经性听力损失（SNHL）患者恢复听力和言语能力。然而，一些患者在人工耳蜗植入后会出现异常的前庭功能，伴有头晕或平衡障碍等症状。人工耳蜗植入时的年龄以及植入方式（单侧或序贯双侧）是否会影响人工耳蜗使用者的前庭功能仍不清楚。为了研究单侧或序贯双侧人工耳蜗植入前后儿童和成人的前庭功能。37例重度或极重度SNHL且适合首次或第二次植入人工耳蜗的患者被分为三组：首次植入人工耳蜗的成人（≥18岁）、首次植入人工耳蜗的儿童（6 - 17岁）和第二次植入人工耳蜗的儿童（6 - 17岁）。所有病例均采用圆窗入路进行植入，以尽量减少对内耳结构造成的损伤。在人工耳蜗植入前及植入后1个月进行冷热试验、前庭诱发肌源性电位（VEMP）测试、视频头脉冲试验（vHIT）、头晕残障量表（DHI）、儿童前庭症状问卷（PVSQ）以及听力测试。首次植入人工耳蜗的成人和儿童在人工耳蜗植入后冷热试验和VEMP测试的异常率较植入前显著增加。植入前VEMP测试显示，首次和第二次植入人工耳蜗的儿童之间异常率显著更高。在首次和第二次植入人工耳蜗的儿童之间或首次植入人工耳蜗的成人与儿童之间，未发现其他异常率的显著差异。在第二次植入人工耳蜗的儿童中，PVSQ评分在植入后第3天显著升高，但在第30天下降。人工耳蜗植入对冷热试验和VEMP测试结果有负面影响，但对vHIT测试结果无影响，这表明耳石和低频半规管（SCC）更容易受到人工耳蜗植入的损伤。人工耳蜗植入手术引起的前庭功能改变可能与人工耳蜗植入时的年龄以及植入方式（单侧或序贯双侧）无关。人工耳蜗植入手术对前庭功能的长期影响以及对耳蜗的慢性电刺激仍有待研究。
