Cochlear implants: indications in groups of patients with borderline indications. A review

Cochlear implants (CI) represent the current treatment for patients affected by profound sensorineural hearing loss (SNHL). Initially only deaf adult patients were considered to be candidates for a CI; however, the development of technology and matured experience have expanded the indications for cochlear implantation. Today, CIs are implanted in adults and children and broader indications are followed. There are, however, a number of patients who do not completely fulfill the current indications and who are potential candidates for CI. The duration of deafness and residual hearing represent prognostic indicators for CI performance; however, the candidacy of children with residual hearing and prelingually deafened adults are still under debate. Anatomical variants such as cochlear ossification, cochlear malformation and chronic otitis media represented and still represent for some surgeons a contraindication to CI. The otological experience of CI surgeons and the advent of auditory brainstem implants have changed the approach to these patients, who may still benefit from hearing rehabilitation. This paper briefly analyses and reviews the results obtained in these groups of patients, who were not, at least initially, considered to be candidates for cochlear implantation.     

Cochlear implantation in the chronically diseased ear

PURPOSE OF REVIEW: The presence of chronic ear disease in patients with profound SNHL presents a challenge to the otologic surgeon and was considered, in the past, a contraindication to cochlear implantation. This review discusses options for cochlear implantation in patients with chronically diseased ears. RECENT FINDINGS: Several management options are available for cochlear implantation in patients with chronic suppurative otitis media (CSOM) and severe to profound sensorineural hearing loss (SNHL). CONCLUSION: Cochlear implantation can be safely achieved in patients with CSOM. The approach chosen should be individualized based on clinical findings.     

Cellular Schwannoma in the Oral Mucosa

Conclusion. Preoperative CT and MRI assessment of children with severe or profound sensorineural hearing loss (SNHL) is critical for determining implant candidacy. Objectives. There are a significant number of children who do not show any auditory development with a cochlear implant (CI), possibly due to cochlear nerve (CN) aplasia/hypoplasia. Regardless of the suspected etiology, if a CI is not providing auditory development the clinician should carefully evaluate the possibility of a CN malformation and re-evaluate the child with detailed neuroimaging studies. If the imaging evaluation shows severe cochlear malformation or CN aplasia there is some developmental urgency to consider auditory brainstem implant (ABI) surgery. Subjects and methods. Twenty-eight children affected by congenital SNHL were examined by CT and MRI. Evaluation of the cerebellopontine angle (CPA), internal auditory canal (IAC), cranial nerves, and membranous labyrinth was performed. Six children had been previously fitted elsewhere with a CI with no sound detection. Results. Suspected congenital anomalies were confirmed by CT and MRI in all 28 children: 16 with associated labyrinthine malformations; 1 with outer, middle, and inner ear malformations; and 2 with associated monolateral facial nerve aplasia.     

Cochlear implantation in a human immunodeficiency virus-infected patient

OBJECTIVES/HYPOTHESIS: Patients infected with HIV have an increased risk of developing sensorineural hearing loss (SNHL), yet pathogenesis of SNHL in HIV infection is still poorly understood. In subjects affected by bilateral profound or total SNHL, cochlear implantation may be the only possibility to restore a hearing level that allows them to have an acceptable quality of life. STUDY DESIGN: Case report. METHODS: A retrospective chart review of a HIV type 1-seropositive profoundly deafened patient who underwent cochlear implantation. RESULTS: To date, with a follow-up of 4 years, the patient has not experienced any complication and has regained useful open-set speech perception. CONCLUSIONS: Cochlear impairment with preserved auditory pathways can be responsible for profound SNHL in HIV-infected patients. Cochlear implantation can restore a social hearing in these patients, dramatically improving their quality of life. The surgical procedure can be safely performed when keeping in mind that the general condition of the patient is the decisive factor for or against surgery.     

Cochlear implantation after traumatic brain injury without otic capsule fracture: A case report and literature review

ObjectiveThe aim of this study was to report a case of cochlear implantation (CI) for a patient with an otic capsule-sparing traumatic brain injury (TBI) and to review the relevant literature.MethodsA patient with history of TBI received a CI for bilateral profound hearing loss. A systematic review of the literature was performed to identify and compare similar cases.ResultsA 36-year-old male with a history of hearing loss from right acute labyrinthitis was referred for bilateral profound sensorineural hearing loss (SNHL) after a fall with associated injury to the central auditory nervous system (CANS) including the brainstem. On the right, behavioral acoustic threshold measurements were in the profound range with absent OAEs. On the left, testing revealed no measurable behavioral acoustic thresholds and variable physiologic measures. A right unilateral cochlear implant was performed with most recent follow-up demonstrating speech awareness thresholds of 25 dB HL with excellent detection of all 6 Ling sounds. However, the patient also continues to suffer from other neurologic sequelae related to his TBI, which challenge his ability to demonstrate objective and subjective benefit. A systematic review of the literature demonstrates variable outcomes for patients with TBI and SNHL.ConclusionsPatients with profound SNHL and TBI present a distinct rehabilitative challenge for clinicians. CI may provide meaningful benefit in this population, though care should be taken in patient selection and counseling.     

The case for earlier cochlear implantation in postlingually deaf adults

Abstract

Objective: This paper aimed to estimate the difference in speech perception outcomes that may occur due to timing of cochlear implantation in relation to the progression of hearing loss. Design: Data from a large population-based sample of adults with acquired hearing loss using cochlear implants (CIs) was used to estimate the effects of duration of hearing loss, age, and pre-implant auditory skills on outcomes for a hypothetical standard patient. Study sample: A total of 310 adults with acquired severe/profound bilateral hearing loss who received a CI in Melbourne, Australia between 1994 and 2006 provided the speech perception data and demographic information to derive regression equations for estimating CI outcomes. Results: For a hypothetical CI candidate with progressive sensorineural hearing loss, the estimates of speech perception scores following cochlear implantation are significantly better if implantation occurs relatively soon after onset of severe hearing loss and before the loss of all functional auditory skills. Conclusions: Improved CI outcomes and quality of life benefit may be achieved for adults with progressive severe hearing loss if they are implanted earlier in the progression of the pathology.     

1例耳蜗前庭神经畸形患者耳蜗植入术前的功能性磁共振评估并文献复习

目的:探讨功能性磁共振(fMRI)评价耳蜗前庭神经畸形患者是否有人工耳蜗植入指征的可能性。方法:对1例15岁双侧耳聋患者,在人工耳蜗植入前进行听力学、影像学检查及fMRI综合评估。结果:纯音测听和听觉脑干反应显示患者为双侧极重度感音神经性聋,瞬态诱发性耳声发射双侧均未引出。颞骨薄层CT显示内耳畸形(不全分隔Ⅰ型),MRI斜矢状位重建显示耳蜗前庭神经畸形。fMRI显示左耳给声,1000Hz100dBHL,右侧听皮层被激活;右耳给声,双侧听皮层均未见激活。左侧人工耳蜗植入术后1个月开机,患者对声音有反应。结论:结合听力学和影像学检查,fMRI可评估人工耳蜗植入候选者,尤其是在影像学检查显示患者耳蜗前庭神经发育畸形时,更是一种有效的评估方法。     

Cochlear implantation in patient with Charcot-Marie-Tooth disease

Two patients with auditory neuropathy spectrum disorder (ANSD) considered to be associated with Charcot-Marie-Tooth (CMT) are reported. In case 1, a 23-year-old man presented with progressive bilateral sensorineural hearing loss (SNHL) from 10 years of age and was diagnosed with ANSD. He was later diagnosed with CMT by neurological testing. In case 2, a 16-year-old girl, the younger sister of the patient in case 1, presented with progressive SNHL with similar auditory findings since 6 years of age as those of her brother. Both cases underwent bilateral cochlear implantation. In case 1, the maximum discrimination score improved to 45% 24 months after the first side of cochlear implantation from 5% before the surgery. In case 2, the score was 5% 10 months after cochlear implant (CI) surgery from 0% before the surgery. CI treatment for CMT patients has been considered difficult because of both failure in synchronization of nerve conduction due to demyelination and axonal failure of the auditory nerve. Though slower progress compared to the average subset of patients receiving CI was seen, significant improvement was gradually observed in the present patients after bilateral cochlear implantations. CI is thus a viable option for rehabilitation of SNHL in CMT patients.     

The correlation between ECochG parameters and early auditory behavior after cochlear implantation in children

Objective: The individual outcome after cochlear implantation in children with auditory synaptopathy/neuropathy (AS/AN) is difficult to predict. A tool for preoperative assessment would be helpful for counseling parents. This study evaluates the outcome after CI in children with AS/AN and with sensorineural hearing loss (SNHL), and correlates it with the preoperative ECochG results in order to find specific parameters of prognostic value. Design: The improvement of auditory behavior after CI was retrospectively assessed using the LittlEARS questionnaire and quantified in a score (LS). This score was correlated with the CAP/SP ratio in the preoperative ECochG. The score was further correlated with the patient’s age six months following CI. Study sample: Nine children with AS/AN were compared to nine children with SNHL. Results: Both groups showed a significant improvement in LS following CI. There was a significant positive correlation between the CAP/SP ratio and the improvement in LS in all children. The correlation between age and LS was significantly negative in the SNHL group and positive in the AS/AN group. Conclusion: All children with AS/AN and SNHL benefit to a similar extent from CI. The preoperatively assessed CAP/SP ratio has a prognostic value for the development of auditory behavior following CI.     

Auditory and speech performance in cochlear implanted ANSD children

Background: Auditory neuropathy spectrum disorder (ANSD) is a distinct type of SNHL that is characterized by the presence of otoacoustic emissions and/or cochlear microphonics. Cochlear implantation was initially not recommended for ANSD children, later studies showed variable outcomes among those subjects.

Objective: To assess the auditory and speech performance of cochlear implanted children with auditory neuropathy spectrum disorder (ANSD) and to compare these results to those obtained from cochlear implanted children with sensorineural hearing loss (SNHL)

Material and methods: 18 cochlear implanted children with ANSD and 40 cochlear implanted children with SNHL were included in this study. Auditory and speech performance results were compared across both subject groups using the Category of Auditory Performance (CAP) and Speech Intelligibility Rate (SIR) tests, with measurements recorded one year post implantation.

Results: Cochlear implanted children with ANSD showed clinically significant improvements that were comparable to those observed from cochlear implanted subjects without ANSD.

Conclusions: Children with ANSD benefit from early cochlear implantation and can reach similar auditory and speech performance results as that achieved by children without ANSD.     

Cochlear implantation following treatment for medulloblastoma

Objectives/Hypothesis:

Medulloblastoma is the most common pediatric malignant tumor of the central nervous system in children. Treatment includes surgical excision, external beam radiation, and multiagent chemotherapy. Otologic sequelae are common and may result from radiation and/or chemotherapy. Profound sensorineural hearing loss (SNHL) is a known complication of neuro‐oncologic treatment and may render these patients eligible for cochlear implantation (CI). Issues of CI in this population, including diagnosis, treatment of preoperative middle ear disease, operative and postoperative course, performance data, and long‐term tumor surveillance are highlighted and reviewed.

Study Design:

Retrospective chart review.

Methods:

Three patients treated for pediatric medulloblastoma with surgical resection, postoperative hyperfractioned craniospinal radiotherapy, and multiagent adjuvant chemotherapy who underwent cochlear implantation were identified. Details of neuro‐oncologic treatment and associated otologic complications are presented and analyzed. Primary outcome assessment includes treatment of middle ear pathology, perioperative cochlear implant course, and postimplantation performance data.

Results:

Each patient required surgical treatment of chronic ear disease 4 to 16 years after chemoradiation. All progressed to profound SNHL and were implanted 8 to 17 years post–neuro‐oncologic treatment. There were no intraoperative complications, and full insertion of the cochlear implant electrode array was achieved in each patient. One patient developed postoperative wound dehiscence requiring operative closure. Postimplantation performance data support significant benefit in all patients.

Conclusions:

Patients treated for pediatric medulloblastoma develop otologic sequelae, including profound SNHL, and may require cochlear implantation. Successful management of middle ear and mastoid pathology involves consideration of potential future cochlear implantation. Postoperative performance data supports cochlear implantation in this population. Laryngoscope, 2010     

Cochlear implantation in chronic demyelinating inflammatory polyneuropathy†

Objective: To describe a case of chronic inflammatory demyelinating polyneuropathy (CDIP) with bilateral sudden sensorineural hearing loss who subsequently benefited from unilateral cochlear implantation.

Methods: case history review and review of the literature for the terms CDIP, hearing loss, cochleovestibular dysfunction, and cochlear implantation.

Results: A 49-year-old woman presented with bilateral rapidly progressive sensorineural hearing loss (SNHL) 1 month after an upper respiratory tract infection. Hearing loss was not responsive to high-dose steroids and there were no other laboratory abnormalities or physical findings. Within 1 month, she developed ascending motor palsy, requiring long-term ventilator support. This neurologic condition was diagnosed as CDIP and she was successfully treated with plasmapheresis and intravenous immunoglobulin. Her hearing never recovered. At the time of cochlear implant, she had no response at the limits of the audiometer and obtained 0% on AzBio testing. No ABR could be recorded preoperatively. She underwent uneventful cochlear implantation with a perimodilar electrode. One year after activation, she had a PTA of 20?dB and 40% on AzBio sentence testing. Her eABR demonstrated a neuropathy pattern. Only two other cases of CDIP associated with dysfunction of the eighth nerve have been described, and neither had documented profound hearing loss.

Conclusions: Severe SNHL associated with CDIP is rare. Although this patient has good access to sound, speech discrimination is poor at 1-year post implantation. This outcome may be due to incomplete recovery of myelination of the eighth nerve. Other possibilities include loss of peripheral nerve fibers due to the initial viral upper respiratory infection, which may lead to less neural substrate to stimulate.     

Surgical outcomes of simultaneous cochlear implantation with subtotal petrosectomy

ObjectiveTo evaluate the surgical outcomes of simultaneous cochlear implantation (CI) with subtotal petrosectomy (SP).MethodsMedical records of thirty-one patients (31 ears) who underwent simultaneous CI with SP in two tertiary referral centers for management of profound hearing loss secondary to chronic suppurative otitis media, cholesteatoma, previous open cavity, temporal bone fracture, and temporal bone irradiation were retrospectively analyzed. Pre and postoperative speech performances and related complications requiring surgical correction were evaluated.ResultsSignificant improvement in postoperative speech performance was observed in all 31 patients compared to preoperative result. Of the 31 patients, complications occurred in three patients (9.6%). One patient exhibited the breakdown of blind sac closure of the external auditory canal and two others exhibited the migration of the receiver-stimulator cochlear implant. The migrations occurred despite tie-down fixation of the device to the skull. The migrated devices were repositioned using revision surgery.ConclusionsSimultaneous CI with SP is an effective and safe surgical method with relatively low complication incidence. However, particular attention should be paid to prevent certain complications. The receiver-stimulator may be predisposed to migrate to abnormal position because it can be placed with lack of tight subperiosteal support at a more superior or posterior location of the skull where the skull curvature changes abruptly than can conventional CI using limited mastoidectomy and posterior tympanotomy approach.     

Cochlear implantation in a patient with sensori-neural deafness secondary to Charcot−Marie−Tooth disease

Abstract

Objective and importance

Charcot?Marie?Tooth (CMT) disease is the most common hereditary motor and sensory neuropathy and can result in profound sensori-neural hearing loss with deficiency in speech perception out of proportion to that which would be expected if the loss was cochlear in origin. This study investigates whether the reintroduction of auditory synchrony by means of cochlear implantation will improve speech perception in those with dys-synchrony related to impairment of temporal processing abilities secondary to CMT.

Clinical presentation

A 67-year-old male presented with a gradual but significant decrease in his hearing as part of a slowly progressing demyelinating peripheral neuropathy. On open-set speech discrimination he scored 0%.

Intervention

A Med-el Flex^SOFT cochlear implant (CI) was fully inserted into the left ear with no surgical complications. The CI speech processor was fitted 1 month post-implantation and standardized speech assessments conducted at 1 week, 3 months, 9 months, and 21 months following initial fitting, gave open-set speech discrimination scores of 0, 0, 53, and 54%, respectively.

Conclusion

This report demonstrates that cochlear implantation is an option to rehabilitate severe-to-profound hearing loss in adults with auditory dys-synchrony secondary to CMT disease. Progress post-implantation is likely to be slower than for the average CI user.     

Cochlear implantation via middle fossa approach – a case report

Objective: Cochlear implantation is routinely performed all over the world via the post-auricular, facial recess approach. Our case study describes the middle fossa approach for the management of bilateral profound sensorineural hearing loss in a female child with multiple external, middle and inner ear malformations. The middle fossa approach has been reported sporadically and has been used inconsistently in patients with chronic otitis media and inner ear malformations.

Case study: A 3-year-old female child presented with bilateral profound sensorineural hearing loss, bilateral anotia, right cochlear nerve agenesis, right facial paralysis, bilateral mild inner ear dysplasia and an aberrant left facial nerve covering the left round window. Further tests indicated that she was a suitable candidate for cochlear implantation and was medically cleared for surgery. In view of the multiple malformations and high risk of injury to her only functioning left facial nerve on the side with a cochlear nerve, cochlear implantation via a middle fossa approach was performed.

Conclusion: Middle fossa approach to cochlear implantation is challenging but can be safely performed even in children and offers an option in patients when a routine mastoidectomy, facial recess and round window approach cannot be undertaken.     

中耳乳突炎性病变的人工耳蜗植入术

目的探索双侧重度感音神经性聋合并中耳乳突炎性病变人工耳蜗植入手术方法.方法 29例不同类型中耳乳突炎患者行人工耳蜗植入手术,根据炎症病变程度采用Ⅰ期手术26例,分期手术3例.非化脓性及慢性中耳炎静止期者,行完壁式乳突根治术,清除病灶,保留骨性外耳道,同期行人工耳蜗植入;化脓性中耳炎者,行完壁式或开放式乳突根治术,清除病灶保留骨性外耳道或重建外耳道后上壁,获得干耳后,Ⅱ期行人工耳蜗植入.结果 29例中耳乳突不同炎症病变患者经Ⅰ期或分期手术,人工耳蜗电极均顺利植入.随访2～8年,无炎症病变复发,开机后人工耳蜗工作正常,无电极裸露、脱出.结论中耳乳突炎性病变经正确的手术措施干预后,可行人工耳蜗植入.强调依据病变程度和范围个性化处理.     

Cochlear implantation in children

Cochlear implantation has revolutionized the treatment and prognosis of children with severe to profound sensorineural hearing loss who receive limited benefits from hearing aids. Children who receive cochlear implantation at young age, in particular before 2 years of age, can be expected to reach their normal age-equivalent developmental milestones and have higher chance to integrate into the mainstream educational settings. With the positive outcomes after cochlear implantation and the improvements in technology and surgical techniques, candidacy for cochlear implantation in children has been expanding to include hearing-impaired children with significant residual hearing, severe inner ear malformations, multiple handicaps such as mental retardation or visual impairment, and auditory neuropathy. Furthermore, there is growing interest in offering bilateral cochlear implantation to give children the benefits of binaural hearing. As the candidacy criteria expand, cochlear implant programs including preoperative evaluation, surgery, and habilitation have become more complex. Therefore, candidates should be selected prudently by multidisciplinary approach and cochlear implantation in children is much better to be provided by experienced cochlear implant team consisting of experts in relevant fields for the best results.     

人工耳蜗植入术295例语言康复临床分析

目的 研究耳蜗植入术后听觉言语康复效果及其影响因素。 方法 采用听觉行为分级(CAP)、言语可懂度分级(SIR)及视频和录音言语清晰度分析法分别对295例人工耳蜗植入术后患者进行听觉言语康复效果评估。 结果 2例蜗神经细小合并内耳畸形患者开机听阈为45 dB,其余听阈为25~40 dB。单因素分析结果显示:术前助听器的佩戴、植入年龄、植入后时间、术前残余听力、内耳畸形程度、脑白质病变对CAP及SIR差异有统计学意义;手术方法、中耳炎、Waardenburg综合征对CAP、SIR差异无统计学意义。多因素Logistic回归分析结果显示:植入后时间、脑白质病变与CAP、SIR显著相关。 结论 大部分患者可从人工耳蜗植入术中获得满意效果,其听觉言语康复程度受多种因素的影响。     

1068例人工耳蜗植入临床经验的总结

目的通过对10年共1068例人工耳蜗植入手术的总结,为深入开展人工耳蜗植入的临床工作提供经验。方法截至2008年2月,对1068例重度以上耳聋患者植入了多导人工耳蜗,其中包括澳大利亚Nucleus678例、奥地利Medel309例、美国AB81例,其中双侧植入2例,Nucleus和Medel各1例。结果①手术成功率：1068例人工耳蜗植入手术均一次成功,手术成功率100％。②手术并发症：术中面神经电钻灼伤2例,术后1～3个月完全恢复;术后伤口水肿和血肿自行恢复15例。③术后问题：术后1个月出现分泌性中耳炎鼓膜穿孔治疗5个月痊愈1例,肥胖体形线圈固定困难3例,术后耳鸣加重5例,术后伤口感染植入体裸露进行转移肌瓣修复5例,术后外伤植入体损坏二次更换3例,原因不清植入体不工作二次更换2例,期望值达不到患者要求取出2例。④术后效果：声场测听〈45dB、汉语言语识别率〉70％共758例,占71％;声场测听〉45dB、汉语言语识别率〈70％共310例,占29％。结论①1068例人工耳蜗植入术后信息反馈显示：本组人工耳蜗植入手术的成功率达到100％,与国内外平均水平相比有显著的优势。②手术并发症较少而且未发生严重并发症,但是麻醉的风险仍不能忽视,尤其是气道痉挛问题。③术后听觉言语康复问题较多,主要是一些患者术后的听觉言语康复效果差而在术前无法进行准确评估。④目前一些特殊的人工耳蜗植入患者,如耳蜗内听道畸形、听神经病、脑瘫、自闭症、弱智、年龄较大术前昕觉言语基础较差者等,术后听觉言语康复效果不佳。