Tinnitus modifications after cochlear implantation

Tinnitus can be defined as a phantom sensation in the absence of an external sound. In our study, we evaluated the effect of cochlear implant on tinnitus evolution. Among adult, postlingually deaf patients who underwent cochlear implantation at our clinic, we selected 20 subjects with pre-implantation tinnitus (group A) and 10 subjects without pre-implantation tinnitus (group B). Pre- and post-surgery tinnitus was assessed through two questionnaires: the first one dealing with tinnitus characteristics and psychosocial impact, and the second one represented by THI, an internationally validated score of evaluation of the effects of tinnitus on patient’s emotions and activities of daily living. None of the patients belonging to group B developed tinnitus after surgery. As for group A, 40% of patients declared suppression of tinnitus, 30% attenuation of tinnitus after surgery, 25% reported tinnitus was unchanged and 5% reported worsening of tinnitus. In the nine patients with bilateral tinnitus (45%), after implantation tinnitus disappeared from both sides in four patients and attenuated bilaterally in four patients. A comparison between pre- and post-implantation THI scores showed decreased score in 65% of cases, unchanged score in 30% and increased score in 5%. The beneficial effect of cochlear implant on tinnitus, reported by a majority of patients, could be due to acoustic masking, to direct electrical stimulation of the acoustic nerve, and above all to a possible cochlear implantation dependent reorganization of the central auditory pathways and associative cerebral areas. In the light of these results, the authors propose (1) to include tinnitus in the selection criteria of which ear to implant; (2) to consider implantation eligibility for patients with bilateral severe hearing loss associated with severe tinnitus; and (3) to inform patients about the small risk of post-operative tinnitus worsening.     

Bilateral cochlear implantation in bilateral Langerhans cell histiocytosis

Abstract

Background

Langerhans’ cell histiocytosis (LCH) is a rare proliferative disorder that can have otologic manifestations in up to 30% of patients. Treatment of local and systemic disease may include medical, surgical, and radiation therapies. Involvement of the temporal bone can lead to conductive and, rarely, sensorineural hearing loss. Post-labyrinthectomy cochlear implantation can be an effective treatment option for sensorineural hearing loss in the setting of persistent LCH.

Methods

A retrospective case review at a tertiary academic medical center. Hearing in Noise Test (HINT) performed before and after bilateral cochlear implantation was examined.

Results

Following bilateral partial labyrinthectomy, post-operative testing showed a HINT in quiet of 17%. Left-sided cochlear implant followed by immunosuppressive therapy for persistent disease showed marked improvement with post-operative HINT in a quiet room of 80% and 63% at 1 and 2 years. Fifty-five months after left implantation, and 10 months after right cochlear implantation, binaural post-operative HINT in quiet was 81%.

Conclusion

Surgical excision of LCH lesion remains a mainstay of treatment for temporal bone involvement. Bilateral cochlear implant with adjuvant immunosuppression in our patient demonstrated both immediate and delayed improvement in auditory function after staged cochlear implantation in the setting of persistent disease.     

Pneumocephalus – an unreported risk of Valsalva's manoeuvre following cochlear implantation

Abstract

We describe a case of pneumocephalus as an unusual early postoperative complication following cochlear implantation. The aetiology of this condition we attribute to the patient's habit of ‘ear popping’ using Valsalva's manoeuvre     

Foreign body reaction after cochlear implantation

Cochlear implantation is a widely accepted, safe procedure for patients with severe to profound sensorineuronal hearing loss. While complications are rare, revision surgeries are required for complications like device failure, misplaced electrode, flap necrosis, and wound infection. Foreign body reaction is a rare complication following cochlear implantation. We experienced a case of foreign body reaction after cochlear implantation treated by device removal. Foreign body reaction has to be considered as one of several causes in cochlear implantation cases that show symptoms mimicking recurrent wound infection or delayed extrusion. We report a case of foreign body reaction with a literature review.     

Long-term complications after cochlear implantation

Objective

Cochlear implantation has become an effective treatment for many profoundly deaf patients. As with any surgical procedure, a proportion of patients suffer postoperative complications. The aim of this study was to analyze long-term postoperative complications in patients with cochlear implants with a view to improve clinical interventions and propose a consensus for reporting complications.

Methods

A total of 406 cases received cochlear implants between December 1985 and April 2007 at Tokyo Medical University (TMU) Hospital. We retrospectively reviewed case notes from 366 patients who had undergone cochlear implantation (215 adults and 151 children) after excluding 40 patients of re-implantation including 13 cases implanted initially at other hospitals. Life-threatening, major and minor complications were examined retrospectively.

Results

Major complications occurred following cochlear implantation in 32 patients (8.7%) who had received their initial implant at TMU Hospital. Revision surgery was required for 30 patients. The mean age at implantation was 33 years 6 months (range, 1 year 9 months to 83 years; median, 37 years). The main etiology of deafness was unknown or progressive (113, 52.6%) in adults and congenital (132, 87.4%) in children. The cause of deafness was meningitis in 41 cases (11.2%), and 26 cases (7.1%) were diagnosed with idiopathic sudden deafness.Flap-related problems (including middle ear infection and/or flap necrosis) developed in 13 cases (3.6%), with 12 cases (7 adults, 5 children) requiring re-implantation. Electrode slip-out occurred in 8 patients (7 adults, 1 child). All adult cases in whom electrodes slipped out underwent implantation before 1994, while the child (1 pediatric case) was operated in 2003. All cases required re-implantation and most cochlear implantations were performed using the modified split-bridge technique after 1997. Six patients (4 adults, 2 children) experienced device failure. Four patients experienced electrode problems. Non-surgical major complications included 1 patient with permanent facial nerve paralysis as a result of thermal injury in 1995.The total number of minor medical and surgical complications was 27, representing 7.4% of all operations.

Conclusion

Many cases of major complications, including electrode problems and facial paralysis, excluding traumatic device failure were considered avoidable by strict operative and postoperative procedures. Some cases of flap infection and traumatic device failure may not be able to be avoided completely, and every possible care should be taken by implant patients and others involved.     

多导人工耳蜗植入后电极阻抗的初步研究

目的研究多导人工耳蜗植入后电极阻抗变化的特点,对比直电极和弯电极的阻抗差异,为人工耳蜗植入术后的调试提供参考。方法在Nucleus多导人工耳蜗编程调试界面上,应用R126V1.3和NRTV3.0软件,测试11例语前聋儿童在不同时期的阻抗值,并进行分析比较。结果CI24M和CI24Rcontour两种植入体阻抗随时间变化的基本规律是:术中较低,开机时最高,以后随时间推移逐渐降低。CI24Rcontour阻抗高于CI24M。结论人工耳蜗植入体阻抗开机后随时间推移而逐渐降低,新型CI24Rcontour植入体与CI24M相比,其阻抗值在术中至开机后3周内明显要高。     

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.     

人工耳蜗植入术后X线投照位置的探讨

目的:确定耳蜗在颅骨的空间位置,设计最佳耳蜗X线摄片投照角度,用于评价电极位置。方法:测量26例耳蜗植入候选患儿术前CT和32例正常成人中内耳CT片上,耳蜗底周与正中矢状线的夹角;并根据测量的X线投射角度拍摄耳蜗位X线平片。结果:蜗轴中线与正中矢状线的角度为40°到68°,平均52.66°;其中儿童组的平均值为52.52°(s=7.07),成人组的平均值为52.80°(s=5.78),两者间差异无显著性意义(P>0.05)。结论:按所测的X线投射角度拍摄的耳蜗平片,能清晰完整显示电极系列的整体和所有的单个电极,确定电极的插入深度和准确的位置,为频率的匹配定位、语言处理方案的优化提供帮助。     

Binaural cochlear implantation after bilateral temporal bone fractures

Abstract

In this clinical note we discuss the indications, feasibility, and outcomes of binaural simultaneous cochlear implantation (CI) following bilateral transverse temporal bone (TB) fractures. A 41-year-old male, totally deaf after a bilateral TB fracture, underwent an audiological, electrophysiological, and imaging investigation in order to assess the integrity of the VIIIth cranial nerves. Five months later he received a simultaneous bilateral CI. Speech perception tests were conducted at different time points. A significant advantage by dichotic listening was observed since the beginning of the habilitation program. The patient achieved a 100% word and sentences recognition in quiet at 12 months. His listening skills in noisy conditions were improved by the use of two implants. A CI in TB fractures is feasible if the VIII nerve is intact and the cochlea is spared by the fracture rim. The early timing of the procedure probably contributed to its success by preventing cochlear fibrosis and ossification.

Sumario

En esta nota clínica discutimos las indicaciones, la factibilidad, y los resultados de la implantación coclear (CI) bilateral simultánea posterior a fracturas transversas bilaterales del hueso temporal (TB). Un varón de 41 años de edad, totalmente sordo después de una fractura bilateral del TB, fue sometido a una investigación audiológica, electrofisiológica y por imágenes, para evaluar la integridad de ambos octavos nervios craneales. Cinco meses después, el sujeto recibido IC bilaterales simultáneos. Se realizaron pruebas de percepción de lenguaje en diferentes momentos. Se observó una ventaja significativa en la audición dicótica desde el inicio del programa de habilitación. El paciente logró un 100% de reconocimiento de palabras y frases en silencio a los 12 meses. Sus habilidades para escuchar mejoraron con el uso de dos implantes. Una IC en fracturas del TB es factible si el VIII par está intacto y la cóclea no está involucrada en el trazo de la fractura. La oportuna realización del procedimiento probablemente contribuyó al éxito al prevenir la fibrosis coclear y la osificación.     

A follow-up study of long-term results after cochlear implantation in children and adolescents

The time course of speech development in children after cochlear implantation may extend over many years, thus making long-term studies necessary to evaluate any outcome. We report our long-term results after cochlear implantation in children and adolescents. Mean follow-up was 28 months, ranging from 1 to 5 years. After at least 1 year of experience all children were found to benefit from their cochlear implants. The majority of children scored above chance in speech identifcation tasks requiring closed set word and sentence understanding). At the 4-year interval, all children tested including prelingually deaf children had developed open set sentence understanding. The most relevant factor accounting for differences in the results was the duration of implant use in all groups. Even beyond 3 years the results continued to improve. Peri- or postlinguallly deafened children tended to have favorable results. For prelingually deaf children, duration of deafness and age at implantation were correlated negatively with the results.     

Improved hearing with cochlear implantation in Fabry's disease

Abstract

Objective

To describe our center's experience with cochlear implantation in patients suffering from Fabry's disease, an inherited mutation resulting in an alpha-galactosidase A enzyme deficiency.

Clinical Presentation

Case report of two patients aged 49 and 59 at implant, with genetically confirmed Fabry's disease and progressive hearing loss.

Intervention

Surgical implantation of Clarion (Advanced Bionics) and Nucleus Freedom (Cochlear) cochlear implants.

Conclusion

Cochlear implantation improves hearing discrimination by 60 points on the HINT scale. This suggests that cochlear implantation is a safe and effective intervention that improves hearing discrimination in patients suffering from Fabry's disease.     

Tinnitus and cochlear implantation

Tinnitus is a common experience, but there is very marked heterogeneity of aetiology, perception and the extent of distress among individuals who experience tinnitus. In view of this, a modern approach to tinnitus should consider homogeneous groups of individuals. This review considers tinnitus experiences in patients undergoing cochlear implantation, this being of interest because the prevalence of tinnitus in this patient group prior to surgery may shed some light on the link between cochlear dysfunction and tinnitus. Second, any change in tinnitus experience as a result of electrode placement surgery or cochlear implant activation has relevance for patient counselling and informed consent. Finally, in recent tinnitus retraining therapy literature there has been the suggestion that unilateral sound therapy for tinnitus patients may set up an unhelpful asymmetry of input to the auditory system, with possible exacerbation of contralateral tinnitus. Unilateral cochlear implant use represents the most dramatic asymmetry possible and hence is a test of that hypothesis. Relevant papers (n = 32) were identified from literature databases. The standard of reporting tinnitus results was inconsistent. Tinnitus is experienced by up to 86% of adult cochlear implant candidates, but is not universal and is only troublesome in a small proportion (reported as 27% in one study). Electrode insertion may induce tinnitus in a small (up to 4%) number of patients, but this is rare. Cochlear implant device use is associated with reduction of tinnitus intensity and awareness in up to 86% of patients, and rarely with exacerbation (up to 9%). There are some indications in the literature that the more complex the simulation strategy, the larger that effect. Specifically, unilateral cochlear implant use was generally associated with reduction of contralateral tinnitus (in up to 67% of individuals) rather than exacerbation, and so the assertion that unilateral sound therapy for tinnitus is contraindicated is not proven.     

Atypical failure after cochlear implantation in children

We report a case of intermittent dysfunction in a 10-years-old boy, implanted with MedEL^® cochlear implant. Few weeks after the surgery the boy described short and intermittent episodes of implant dysfunction with rapid return to a normal function. No evidence for any electric or neural dysfunction was found. After few weeks, a clinical link was discovered to episodes of sneeze or nose blowing. Clinical and surgical implications are discussed.     

语前聋儿童人工耳蜗植入后的调机与声场评估

目的 调查语前聋儿童人工耳蜗植入术后声场主观测听阈值和对应T值的变化趋势。方法 28例人工耳蜗植入儿童。年龄3—6岁。无耳蜗畸形，植入后电极阻抗测试完全正常。对开机后3月、6月和1年时间的声场主观测听阈值与T值的变化进行了统计分析。结果 声场测听阈值在开机1年中呈逐渐降低趋势，开机1年时声场测听的听力水平较3个月和6个月有明显提高（P〈0．05）。植入者术后一年声场主观测听（啭音）听阈为15—35dB HL，听力水平较术前有明显提高。28例植入者T值在开机一年后明显低于六个月和三个月的水平（P〈0．05）。结论 开机后一年内T值和声场测听阈值都呈逐渐下降趋势．并且与3个月和6个月的水平差异具有统计学意义。植入者在熟悉适应了电声信号后，可以在刺激电流强度下降的同时获得更好的听力。     

Effect of preoperative residual hearing on speech perception after cochlear implantation

Objective: To assess the effect of substantial preoperative residual hearing on speech perception outcomes in adult cochlear implant recipients. Setting: Tertiary care academic referral center. Methods: Twenty‐nine patients with substantial preoperative residual hearing underwent cochlear implantation. Twenty‐one implant recipients matched for age and duration of hearing loss, but without preoperative residual hearing, served as controls. Postoperative speech perception was assessed using City University of New York sentence, consonant‐nucleus‐consonant, and hearing in noise test in quiet and in noise (+10 dB signal to noise ratio) tests at 1, 3, 6, and 12 months after fitting. Results: After implantation, there were no significant differences between groups for any of the tests administered. The mean change in speech perception abilities from baseline was significantly greater for the control patients than those with substantial preoperative residual hearing at a number of the test intervals across the various conditions. Moreover, at both 1 and 3 months, some patients in the residual hearing group had speech perception scores that were worse than their preoperative values. Ultimately, all of the patients with substantial residual hearing surpassed their preoperative performance. Discussion: Patients with substantial preoperative residual hearing can gain significant benefit from cochlear implantation. Although the degree of improvement in these individuals is somewhat more modest than for those patients without preoperative residual hearing, the outcomes are still excellent. That there were no significant differences between the patient groups suggests that having substantial residual hearing before implantation does not provide a measurable performance advantage for electrical stimulation. Patients with substantial residual hearing who are contemplating cochlear implantation should be counseled regarding a possible initial decline in speech perception performance.