Filipo Roberto, Patrizi Mario, La Gamma Raffaella, D'Elia Chiara, La Rosa Giovanni, Barbara Maurizio
Department of Neurology and Otorhinolaryngology, I Medical School, University of Rome La Sapienza, via Grottarossa, Rome Italy.
Acta Otolaryngol. 2006 Dec;126(12):1266-74. doi: 10.1080/00016480600678789.
Cochlear implantation (CI) may induce vestibular impairment soon after surgery as well as after implant activation. This impairment seems to be independent from the cause of deafness and can be considered a possible complication from the intra-operative trauma and, to minor degree, from the ongoing electric stimulation. It would also seem that vestibular damage occurs independently from the likelihood of post-operative hearing deterioration. In unilateral selected CI cases, vestibular examination can be proposed as additional pre-operative exam for selection of the ear to be implanted.
This study has been planned in order to get evidence of eventual impairment of the vestibular apparatus after cochlear implantation as well as to verify whether the impairment could be related to different variables, such as cause of deafness, concomitant hearing deterioration, surgical trauma and duration of electrical stimulation.
Charts from two different populations of implantees have been reviewed, 21 from a prospective, 72 from a retrospective study, respectively. All the patients were implanted with Clarion(R) devices of different generation. Vestibular testing was based on rotatory, caloric (when possible) and stabilometric measurements, which were carried out pre-operatively and at the following different times: 5 weeks after CI surgery, and 30, 60 and 90 days after CI activation. Hearing thresholds were also assessed in those patients who showed signs of vestibular impairment as well as in a group of patients without vestibular disorders (control). Patients belonging to the retrospective group were all asked to fill a questionnaire regarding their balance condition. Results. In 14.3% of the prospective study group, a grade I and II spontaneous nystagmus was evidenced pre-operatively and remained unchanged during the whole assessment period. A grade II spontaneous nystagmus was present in 3 patients (21.4%) of the same group after surgery. In the immediate post-operative period, vestibular impairment was displayed as true rotational vertigo in 21.4% and unsteadiness in 42.8% of the study group. Severe unsteadiness was present during the first 2 days after activation in 14.3% of the subjects. In 21.4% of the patients a VPPB episode occured. In the retrospective study group, 26.4% of the subjects referred pre-operative dizziness and 25 patients (34.7%) referred immediate post-operative vertigo episodes, which remained in a milder form after CI activation in 12% of them. The hearing threshold showed to deteriorate in both vestibular-impaired and control CI population without significant difference.
人工耳蜗植入（CI）术后及开机后可能很快导致前庭功能损害。这种损害似乎与耳聋病因无关，可被视为术中创伤以及在较小程度上持续电刺激引起的一种可能并发症。前庭损害似乎也独立于术后听力下降的可能性发生。在单侧选择性CI病例中，可建议进行前庭检查作为植入耳选择的额外术前检查。
本研究旨在获取人工耳蜗植入后前庭器官最终是否受损的证据，并验证这种损害是否与不同变量相关，如耳聋病因、伴随的听力下降、手术创伤和电刺激持续时间。
回顾了来自两个不同植入者群体的病历，分别来自一项前瞻性研究的21例和一项回顾性研究的72例。所有患者均植入了不同代的Clarion®设备。前庭测试基于旋转、冷热试验（如有可能）和姿势稳定测量，在术前以及以下不同时间进行：CI手术后5周，CI开机后30、60和90天。还对那些有前庭功能损害迹象的患者以及一组无前庭疾病的患者（对照组）进行了听力阈值评估。回顾性研究组的所有患者都被要求填写一份关于其平衡状况的问卷。结果：在前瞻性研究组中，14.3%的患者术前有I级和II级自发性眼球震颤，在整个评估期间保持不变。同一组中有3名患者（21.4%）术后出现II级自发性眼球震颤。在术后即刻，研究组中21.4%的患者表现为真性旋转性眩晕，42.8%的患者表现为不稳。开机后头2天内，14.3%的受试者出现严重不稳。21.4%的患者发生了VPPB发作。在回顾性研究组中，26.4%的受试者术前有头晕症状，25名患者（34.7%）术后即刻有眩晕发作，其中12%的患者在CI开机后眩晕仍为较轻形式。在前庭功能受损组和对照CI组中，听力阈值均显示下降，无显著差异。
