Translabyrinthine vestibular schwannoma resection with simultaneous cochlear implantation

Objectives: (1) Report a rare case of translabyrinthine resection of a sporadic vestibular schwannoma (VS) and concurrent cochlear implantation (CI). (2) Discuss pre-, intra-, and post-operative considerations in this unique patient population. (3) Describe surgical and audiologic outcomes reported in this population.

Methods: Case report and review of the literature. PubMed search ‘Cochlear Implantation’[Mesh] AND (‘Neuroma, Acoustic’[Mesh] OR ‘VESTIBULAR SCHWANNOMA’[All Fields] OR ‘SCHWANNOMA’[All Fields]) limited to humans and English language. Returned 64 search results, abstracts and references of relevant papers reviewed.

Results: A 75-year-old male with longstanding history of slowly progressive severe hearing loss and tinnitus presented for evaluation of worsening imbalance, vertigo, and nausea. Workup revealed a 7?mm right intracanalicular mass on MRI concerning for vestibular schwannoma. Audiogram showed bilateral, symmetric, severe-to-profound sensorineural hearing loss, with poor open-set speech comprehension while bilaterally aided. He underwent successful concurrent right translabyrinthine resection of his VS with complete preservation of the cochlear nerve and uncomplicated cochlear implantation.

Discussion: Literature review revealed few previous reports of simultaneous VS and CI. The vast majority of these were in patients with neurofibromatosis Type 2 in whom auditory outcomes were poor. This patient represents one of the few cases of concurrent translabyrinthine tumor removal and CI for a spontaneous VS.

Conclusion: Single-stage cochlear implantation and translabyrinthine tumor resection is a feasible and safe option to consider for auditory rehabilitation in rare situations.     

Vestibular evoked myogenic potentials in children after cochlear implantation

Objective

The aim of this study was to report the effect of unilateral cochlear implantation to vestibular system using vestibular evoked myogenic potentials (VEMPs) by air-conduction in a sample of children aged less than 5 years.

Materials

This study consisted of 10 children (6 boys and 4 girls), who underwent cochlear implantation surgery at our clinic, and 8 normal hearing children (5 boys and 3 girls) matched for age. The VEMPs were performed before, 10 days, and 6 months after surgery. Both the implanted and unimplanted ears of each child were evaluated, with the cochlear implant both off and on.

Results

Preoperatively, six (60%) children had abnormal VEMPs responses on both ears. In the postoperative sessions, no child showed any VEMPs response on the implanted side. The VEMPs were not recorded on the unimplanted side either, except for one case. At 6 months, the VEMPs response on the unimplanted side of three children became normal when the cochlear implant was on, and in two children with the device off.

Conclusion

In the postoperative 6-month-period, the disappearance of VEMPs suggests that the saccule of children can be extensively damaged following cochlear implantation. A recovery of VEMPs can take place on the unimplanted side, with the cochlear implant both on and off. Despite this saccular injury, the absence of clinical signs in children could be explained by their ability to effectively compensate for such vestibular deficits.     

Impact of cochlear implantation on peripheral vestibular function in adults

ObjectiveCochlear implantation may have a detrimental effect on vestibular function and residual hearing. Our goal was to investigate the impact of cochlear implantation on peripheral vestibular function and the symptomatology that ensues.Material and methodsA prospective observational study included all adults undergoing cochlear implantation by the same operator between July 2014 and December 2015, with pre- and postoperative (4 months) neurovestibular balance examination comprising a questionnaire and clinical tests [head impulse test (HIT), head-shaking test (HST), skull vibration test (SVT)] and instrumental tests [caloric test of the lateral semicircular canal and cervical vestibular-evoked myogenic potentials (cVEMP)].ResultsTwenty-two patients were included, with a mean age of 62 years and sex-ratio of 1.2. Before implantation, 50% of subjects (n = 11) reported at least one episode of vertigo associated with balance disorder during their life. After implantation, there were 11 cases of vertigo but only one patient described persistent discomfort related to vertigo 4 months after surgery. Patients with impaired vestibular function after 4 months, taking all symptoms together, were all aged more than 75 years. HIT was abnormal in 18% of cases before implantation and in 59% after (P = NS). HST showed nystagmus in one patient both before and after surgery. Only 18% of patients showed nystagmus induced by SVT before surgery, increasing to one-third after surgery (P = NS). Caloric test of the lateral canal showed hypofunction in 50% of cases before surgery, including 10% of cases with areflexia. This rate increased after surgery to 58%, with 18% areflexia (P = NS). cVEMPs were not detected in 68% of cases before implantation and this rate increased to 86% after surgery (P = NS). There were no significant associations (P > 0.05) between test results and symptoms.ConclusionsIn the medium term, although older subjects more frequently presented vestibular disorder, cochlear implantation induced little vertigo or balance disorder, sometimes even improving vestibular function. However, vestibular disorders were frequent preoperatively and increased postoperatively. We tested vestibular function on different stimulation frequencies and yet found no correlation between postoperative test results and postoperative vertigo.     

单纯前庭导水管扩大行人工耳蜗植入患儿临床特征回顾性研究

目的　回顾性研究已行人工耳蜗植入的单纯前庭导水管扩大患者临床资料,研究其发病与植入年龄分布情况、手术并发症、发病诱因,为临床前庭导水管扩大诊疗提供依据。方法　回顾性研究2000年1月～2015年4月345例经颞骨CT诊断为单纯前庭导水管扩大并于北京同仁医院行人工耳蜗植入患儿临床资料,包括发病诱因、发病年龄、语前/语后聋情况、植入前听力水平及助听器使用情况、手术并发症,分析不同年龄段的发病特点、人工耳蜗植入情况、病程与佩戴助听器的关系,并对不同发病诱因进行分类总结。结果　单纯前庭导水管扩大患者发病年龄的中位数为1（0,2）岁,植入年龄的中位数为3.75（2.17,12）岁。大部分病例（276/345例）无明显诱因,有明确家族史者27例 （7.9%）,外伤所致听力下降者14例（4.1%）,感冒后诱发者10例（2.9%）,使用耳毒性药物所致者13例（3.8%）,有麻疹病毒感染史2例（0.6%）,1例为早产儿胆红素脑病所致。术中“井喷”发生率21.16%,无其他并发症。随病程延长佩戴助听器者比例增加,且两者之间具有显著相关性。结论  单纯前庭导水管扩大患者的发病年龄1岁左右,植入年龄3～4岁,病程越长术前曾使用助听器比例越高。此类患者大部分为不明原因听力下降,此外尚有部分是外伤、感冒或使用耳毒性药物所致,所以诊断为前庭导水管扩大的患者要积极避免以上诱因。前庭导水管扩大发病后要及时诊治,听力下降即考虑佩戴助听器,助听器不能补偿时需积极行人工耳蜗植入。     

Evaluation of postural control in unilateral vestibular hypofunction

IntroductionPatients with vestibular hypofunction, a typical finding in peripheral vestibular disorders, show body balance alterations.ObjectiveTo evaluate the postural control of patients with vertigo and unilateral vestibular hypofunction.MethodThis is a clinical cross-sectional study. Twenty-five patients with vertigo and unilateral vestibular hypofunction and a homogeneous control group consisting of 32 healthy individuals were submitted to a neurotological evaluation including the Tetrax Interactive Balance System posturography in eight different sensory conditions.ResultsFor different positions, vertiginous patients with unilateral vestibular hypofunction showed significantly higher values of general stability index, weight distribution index, right/left and tool/heel synchronizations, Fourier transformation index and fall index than controls.ConclusionIncreased values in the indices of weight distribution, right/left and tool/heel synchronizations, Fourier transformation and fall risk characterize the impairment of postural control in patients with vertigo and unilateral vestibular hypofunction.     

Herpes simplex meningo-encephalitis following cochlear implantation: A case study

Abstract

Objective and importance

Herpes simplex virus (HSV) is reported to be the most common cause of viral encephalitis. Although extremely rare, reactivation of the virus has been reported following central nervous system surgery. To the best of our knowledge, there is no report in the literature that describes HSV encephalitis following cochlear implantation.

Clinical presentation

We report a case of meningo-encephalitis occurring 17 days after cochlear implantation using an electro-acoustic stimulation device, with oerioperative steroid medication. Intensive anti-viral therapy was given and the patient recovered from the acute illness over 2 weeks. Agitation and anxiety followed the encephalitis and subsequent progress with the cochlear implant was slow. Twelve months after cochlear implantation this patient shows a gradual and steady progress with her hearing rehabilitation.

Conclusion

Cochlear implantation surgery was either coincidental or was the trigger factor for reactivation of the HSV. Surgeons must be vigilant to post-surgical meningism symptoms particularly if patients have a history of herpes infections.     

Double challenge: cochlear implantation in the only hearing ear with progressive hearing loss following meningitis and vestibular dysfunction after implantation

ObjectiveVestibular dysfunction associated with cochlear implantation is rare. It is usually seen in patients with otosclerosis due to spread of electrical activity throughout the demineralized bone. A 17-year old female with progressive hearing loss 2 years after meningitis and vestibular dysfunction in the implanted ear is presented in this study.FindingsThe patient had mild hearing loss in the right ear and total hearing loss on the left side because of complete ossification of the cochlea following meningitis. She had to have cochlear implantation in the right ear because of progression of hearing loss. She had successful implantation but she experienced vestibular dysfunction following activation of cochlear electrodes. Closure of two electrodes caused disruption of auditory programming. Then the patient was subjected to long term vestibular rehabilitation program.ConclusionTiming for implantation before the completion of cochlear ossification is crucial not to miss the chance for hearing restoration. However, difficulties in hearing rehabilitation due to extensive ossification can be doubled by vestibular problems triggered by stimulation of the vestibular nerve by cochlear electrodes. Attempts to reduce the balance problem will complicate auditory programming. Vestibular rehabilitation for long term helps to carry on hearing progress.     

A case of improved hearing with cochlear implantation in Gaucher disease type 1

Gaucher disease is a lysosomal storage disorder that is caused by congenital defective function of the enzyme glucocerebrosidase. Glucocerebroside that is not hydrolyzed by glucocerebrosidase mainly accumulates in the reticular tissue. We describe a Japanese boy with Gaucher disease type 1 who developed bilateral profound sensorineural hearing loss within approximately 4 years. We performed cochlear implantation initially on his right ear and again on his left ear 5 months later. The cochlear implants were successfully utilized with a speech discrimination score of 95% on a Japanese sentence recognition test. There are many reports of central hearing loss in Gaucher disease type 2 or 3. However, to the best of our knowledge, this is the first report of profound inner ear hearing loss with Gaucher disease. It also appears to be the first record of cochlear implantation for Gaucher disease. Cochlear implants may be useful for sensorineural hearing loss in patients with Gaucher disease without neurological symptoms other than hearing loss.     

Outcomes of cochlear implantation in patients with neurofibromatosis type 2

In neurofibromatosis type 2 (NF2) bilateral vestibular schwannomas (VS) or their treatment usually results in bilateral hearing loss. Cochlear implantation (CI) was traditionally not used in these patients due to concern that retrocochlear disease would render the implant ineffective. This paper describes the auditory outcomes of CI in 13 patients with NF2 and includes patients with untreated VS and patients undergoing VS removal with cochlear nerve preservation. The non-user rate was 7.7%. Of the active users, median CUNY score was 98%, median BKB score in quiet was 90% and median BKB score in noise was 68%. CI is a viable option in selected patients with NF2.     

前庭水管扩大综合征患者的人工耳蜗植入术

目的　评价前庭水管扩大综合征患者人工耳蜗植入术的安全性和可行性。方法　 1995年 5月 1日～ 2 0 0 2年 6月 1日因双耳重 极重度感音神经性聋在北京协和医院接受人工耳蜗植入术的患者 312例中诊断为双耳前庭水管扩大者 10例 (3 2 % ) ,其中语前聋 7例 ,语后聋 3例。回顾性分析这 10例患者的临床资料。结果　 10例患者人工耳蜗电极植入顺利 ,8例耳蜗底回开窗时发生轻度井喷 ,迅速用颞肌筋膜牢固封闭圆窗制止井喷。全部患者术后未出现脑脊液漏、颅内感染、面瘫、中耳炎等并发症。开机 6个月时 8例患者具有开放性言语识别力 ,已进入普通学校 (幼儿园、小学、大学 )就读。另 2例语前聋的幼儿视觉强化测听听阈达 4 0dBHL ,与其他无内耳畸形的全聋儿童术后效果差异无显著性。全聋前语言能力较好的 5例患者术后语言能力明显好于语前聋的患者 ,语言交流基本听不出聋人特有的语音特征。另 5例患者语言均有不同程度的进步。结论　尽管前庭水管扩大患者在人工耳蜗植入术中可能出现井喷 ,但术后未出现并发症且听力 言语康复效果好 ,因此重 极重度聋的前庭水管扩大综合征患者行人工耳蜗植入术是安全可行的     

Use of MRI to determine cochlear duct length in patients undergoing cochlear implantation

Objectives: It is recognised that CT can be used to determine the cochlear duct length (CDL) when selecting an electrode for cochlear implantation. It is the practice of our institution to routinely use MRI as the sole modality of pre-operative imaging in the assessment of children referred for consideration of cochlear implantation. We therefore wanted to determine whether MRI could be reliably used to determine cochlear duct length.

Methods: An analysis of 40 ears that had undergone MRI and CT of the temporal bones was undertaken. The diameter of the basal turn was independently measured for each ear using the two modalities, and CDL was then calculated.

Results: The mean error of measurement was 0.26?mm (range 0–0.8?mm), leading to a difference in calculated CDL of 0.96?mm (range 0–2.92?mm). CDL did not predict full insertion of 28?mm cochlear implant electrodes in 30 ears.

Conclusions: MRI can be used to reliably determine cochlear duct length.     

Paediatric cochlear implantation: the views of parents

The purpose of this study was to understand the parental perspective on paediatric cochlear implantation over time. Face-to-face semi-structured interviews were conducted with 216 families of children who were implanted at the Nottingham Paediatric Cochlear Implant Programme between 1989 and 2002, and who were attending an appointment during the study period (July 2001–August 2002). The qualitative data revealed that time played an important role in family experiences of paediatric cochlear implantation. Expectations were continually revised throughout the process, as a result of new knowledge and new technological developments. The results show that outcomes are highly individualistic although parents had a shared hope of the implant enabling the child to function in a “hearing world”; that the biggest area of contention is in respect of their child's education; and that parents talked openly about constraints imposed on them by implantation. The vast majority of parents did not regret their decision to proceed with implantation.     

The experience of bilateral cochlear implantation in a child with LEOPARD syndrome

We present a 3-year old boy with Leopard syndrome. His clinical manifestations included a congenital bilateral sensorineural hearing loss. He underwent cochlear implantation on the right side at age 1 year and on the left side at age 1.5 years. The patient is doing very well and mainstreamed in a regular pre-school program with a teacher of the deaf and home based speech therapy. Bilateral cochlear implantation in the case of a child with Leopard syndrome can be successful.     

人工耳蜗植入后对侧耳是否联合使用助听器声调识别的对比研究

目的 探讨人工耳蜗植入后对侧耳联合使用助听器对声调识别的影响;同时探讨人工耳蜗开机时间、康复训练时间、听障儿童的学习能力等因素对声调识别的影响。 方法 选择3~7岁的人工耳蜗植入儿童27例,采用《言语听觉反应评估》(EARS)中的“封闭式声调测试”作为测试材料,分别单独使用人工耳蜗(CI)和在人工耳蜗对侧耳联合使用助听器(CIHA)在安静和噪声两种环境下进行声调识别的测试,使用SPSS 17.0对测试结果进行统计学分析。 结果 无论在安静环境还是噪声环境下,CIHA的声调测试成绩均优于CI,此优势在噪声环境下更明显;人工耳蜗开机时间、康复训练时间较长者声调测试成绩均优于较短者;听障儿童的希-内学习能力测试结果学习能力DIQ≥100与DIQ<100者声调测试成绩差异无统计学意义。 结论 建议听障儿童人工耳蜗植入后对侧耳联合使用助听器,但助听器需要优化和调整。     

人工耳蜗植入术残余听力保留现状和研究进展

随着手术方法和电极设计等技术的创新,人工耳蜗手术取得了一定的进步,使患者残余听力得到一定的保留。所有手术方法的共同目标即是：保护耳蜗内结构,保留残余听力,以提高听觉言语能力。人工耳蜗术后残余听力的丧失被认为是多种因素的结果,近年来,为获得更好的残余听力保留,人们在电极设计与选择、新型电极涂层、围手术期药物治疗、机器人辅助、图像和电生理引导等方面的研究有了新的突破,对于残余听力的保护有了很大程度的提高。本文将对人工耳蜗术后残余听力保护相关因素的进展作一综述。     

Bilateral cochlear implantation in Friedreich's ataxia: A case study

Abstract

With an incidence of 1:29 000 among Caucasians, Friedreich's ataxia (FRDA) is the most common inherited ataxia, leading to both sensory and motor degeneration. Despite many FRDA patients exhibiting normal or near normal sound detection thresholds, many individuals show abnormal neural conduction along their central auditory pathways. Electrophysiological testing can show abnormal or absent cochlear nerve and auditory brainstem recordings in the presence of normal pre-neural cochlear function (otoacoustic emissions or cochlear microphonics). This pattern of normal pre-neural cochlear function and disrupted neural conduction has been termed auditory neuropathy spectrum disorder (ANSD). Studies of FRDA patients with ANSD have shown that they exhibit severe deficits in temporal processing, impaired frequency discrimination, and deficits in speech perception. Rehabilitation of these auditory percept deficits remains difficult, as hearing aids may amplify sounds without adding clarity to the temporally disrupted or distorted signal that FRDA patients with ANSD may receive. There is limited data on the best intervention for patients with FRDA with ANSD, although personal radio aids (FM systems) have been shown to be beneficial. We report a case, where cochlear implantation has led to a dramatic improvement in speech perception in an individual with FRDA and ANSD. The majority of the literature on ANSD treatment has focused on paediatric patients with the ‘dyssynchrony’ type of ANSD, rather than the true neuropathy type underlying the hearing loss in FRDA patients.     

鼓岬区底转骨螺旋板的分段定位及其临床意义

目的:为耳蜗植入术提供耳蜗鼓岬区底转骨螺旋板的解剖资料,同时寻找从鼓岬表面定位骨螺旋板的方法.方法:取成人颞骨标本15例(30侧),经乳突后鼓室进路,进入鼓室;在手术放大镜下对鼓岬区骨螺旋板走行、分段及毗邻结构进行观测.结果:①耳蜗底转骨螺旋板在鼓岬区可通过位于蜗窗龛上缘及下部的转折点分成3段:钩段(1.52±0.16)mm,蜗窗前下段(3.83±0.37)mm和前行段(2.70±0.36)mm;②蜗窗前下段所在平面与面神经水平段成角为(51.00±5.97)°,且较恒定地与镫骨头后缘相交;以镫骨头后缘为一固定点,在鼓岬上画一经过此点与面神经水平段成51°的直线,可代表骨螺旋板蜗窗前下段在鼓岬上的投影,也即此段骨螺旋板在鼓岬上的投影线;③鼓岬区鼓阶宽度:蜗窗龛上缘中点处宽度为(0.36±0.06)mm;蜗窗龛前缘中点处宽度为(0.97±0.14)mm;蜗窗前下3 mm处宽度为(1.24±0.21)mm.结论:①鼓岬区骨螺旋板可通过2个转折点分成3段,即钩段、蜗窗前下段和前行段;②骨螺旋板在鼓岬上的投影线及与毗邻结构的距离可以为人工耳蜗植入术中准确定位鼓阶,避免损伤基底膜提供形态学依据.     

The effect of cochlear implants on vestibular-evoked myogenic potential responses and postural stability

Objective

Current spread by electrical stimulation via inserted cochlear implant (CI) electrodes and the consequential increase in sound input can affect the equilibrium of patients. The aim of the present study was to clarify the effect of CIs on the equilibrium of patients through cervical vestibular-evoked myogenic potential (cVEMP) testing and static stabilometry performed with the CIs turned on (CI-on) and off (CI-off).