Simultaneous translabyrinthine removal of acoustic neuroma and cochlear implantation

Objectives

To report of a 65-year-old woman with bilateral Meniere's disease was referred for cochlear implantation (CI) due to severe/profound sensorineural hearing loss.

Methods

During the assessment workup, a vestibular schwannoma in the right ear was found by MR imaging. She underwent a translabyrinthine removal of the acoustic neuroma (AN) with sparing of the cochlear nerve and concurrent ipsilateral CI with a Nucleus Freedom device (Cochlear Ltd., Lane Cove, New South Wales, Australia).

Results

Complete removal of the AN was achieved without complications. Neural Response Telemetry (NRT) measurements, which showed poor morphology at the intraoperative tests, rapidly improved after activation, similarly to electrically evoked auditory brainstem responses (E-ABR). The patient reached 100% speech perception performances within 2 months from implantation, in the monaural condition. She was relieved from vertigo spell up to 14 months after the operation.

Conclusion

Cochlear implantation at the time of acoustic neuroma removal with VIII nerve sparing can be a safe and effective hearing restoration procedure.     

扩大迷路径路切除经枕下径路手术后复发的听神经瘤

目的：探讨听神经瘤经枕下径路手术后复发、后经扩大迷路径路再次切除肿瘤的方法及效果。方法：对5例复发的听神经瘤患者，采用扩大迷路径路手术，在经典迷路径路的基础上，通过充分切除岩骨骨质扩大手术视野，将复发的肿瘤组织完全切除。结果：5例听神经瘤直径为2．5～4．0cm，均全部切除，无死亡病例，未发生颅内感染及脑脊液漏；面神经功能与术前一致；术后CT和MRI复查均显示无肿瘤残存，小脑、脑干位置恢复正常。经0．5～2年7个月的随访，至今未见复发，患者已恢复正常生活和工作。结论：枕下径路手术容易残留内听道内的肿瘤，再次手术采用扩大迷路径路可直接暴露肿瘤并到达脑干，既可避免瘢痕粘连区，方便定位面神经，又能全部切除复发的肿瘤，且具有创伤小、面神经功能保存完好等优点。     

Physiological identification of the auditory nerve during surgery for acoustic neuroma

We report the design and clinical use of an electrode which can locate the acoustic nerve fibres in the normal eighth nerve and also in eighth nerves deformed by acoustic neuromas. The improvement in facial nerve preservation during acoustic neuroma surgery is partly due to the use of a facial nerve stimulator to anatomically locate the fibres. Our new acoustic nerve detector has the capability of anatomical location of cochlear fibres which may help to improve hearing preservation in selected cases of acoustic neuroma. The device functions by detecting the compound action potential evoked by no frequency auditory simulation at 500 Hz. The 500 Hz compound action potential is detected with a bipolar probe and then amplified and filtered. This results in a 500 Hz tone when the probe contacts the auditory nerve. Detection is virtually instantaneous. The acoustic nerve detector (AND) is demonstrated in a normal eighth nerve complex and its use is then described in the total removal of an acoustic neuroma with a 1 cm extracanalicular extension in which useful hearing was saved post-operatively. The present prototype may not be sensitive enough to detect the very low signals that may result when cochlear fibres are widely distorted around a large tumour or in cases where slight contusion of the nerve occurs during dissection. In all other cases the real time anatomical information is extremely helpful in guiding acoustic nerve dissection and also in monitoring the effects of petrous bone drilling.     

Cochlear implantation in the neurofibromatosis type 2 patient: long-term follow-up

OBJECTIVE: To evaluate the long-term hearing outcomes of neurofibromatosis type 2 (NF2) patients with cochlear implants. METHODS: Retrospective analysis of cochlear implant performance in NF2 patients using open- and closed-set speech perception testing. RESULTS: Patients with NF2-associated bilateral vestibular schwannomas frequently become profoundly deaf. The aim of surgical resection should be to preserve serviceable hearing in at least one ear; however, this goal can be difficult to achieve. Frequently, tumor size or poor preoperative hearing status can require a surgical approach that leaves the patient with a profound, bilateral sensorineural hearing loss. If the cochlear nerve is preserved anatomically after vestibular schwannoma surgery, and if promontory stimulation confirms the functionality of the cochlear nerve, then cochlear implantation is an excellent option to restore hearing. We present six cochlear implant patients with NF2 who attained a significant improvement in open- and closed-set speech understanding with a mean follow-up of 7.9 (range: 5-13) years after surgery. In all but one case, the hearing results did not deteriorate over the follow-up period. CONCLUSION: Early surgical intervention for vestibular schwannomas in NF2 patients when the cochlear nerve can be spared is an important consideration to allow for possible cochlear implantation. A 6- to 8-week recovery period for the anatomically intact cochlear nerve may be necessary to obtain a positive promontory stimulation response following tumor resection and should be performed prior to cochlear implantation.     

耳内镜辅助下听神经瘤切除术

目的:观察耳内镜辅助下听神经瘤切除术的疗效及并发症.方法:在硬管耳内镜辅助下采用迷路进路及乙状窦后进路行听神经瘤手术11例.结果:肿瘤全切除9例(81.8%),2例(18.2%)残留部分囊壁;术中内镜下探查面神经均完整.其中9例(81.8%)术后无面瘫表现,2例(18.2%)术后出现轻度周围性面瘫;术中内镜下探查蜗神经均完整,2例(18.2%)术后听力与术前比较保持不变,9例(81.8%)出现不同程度听力下降,其中,中度感音神经性聋1例,中重度2例,重度3例,极重度3例.结论:听神经瘤切除术中使用耳内镜可提高血管、神经保全率及肿瘤全切率,但也有其不足,仅能作为显微镜手术的辅助手段.     

经迷路进路听神经瘤术后脑脊液漏的预防及处理

目的　探讨经迷路进路听神经瘤切除术后脑脊液漏发生的影响因素及处理方法。方法1999年以来采用迷路进路或扩大迷路进路听神经瘤切除术 85例 ,前 4 1例采用传统关闭术腔技术 ,后4 4例对关闭技术进行改良 ,分析其脑脊液漏的发生率。发生脑脊液漏者行保守或手术治疗。结果传统关闭技术组中脑脊液漏的发生率为 19 5 % ( 8 4 1) ,改良关闭技术组中脑脊液漏的发生率为 2 3%( 1 4 4 ) ,两组差异有显著性意义 (P =0 0 13)。传统关闭技术组中脑脊液漏多数发生在大型听神经瘤中 ,其发生率随肿瘤增大有上升的趋势。 9例脑脊液漏的患者中 ,3例经保守治疗 ;6例经手术修补成功 ,其中 5例 1次修补成功。结论　改良关闭术腔技术可显著降低经迷路进路听神经瘤切除术后脑脊液漏的发生率 ,手术修补为终止脑脊液漏的有效措施     

经迷路径路听神经瘤手术中对颈静脉球的处理

目的探讨经迷路径路听神经瘤手术中处理颈静脉球的方法和临床疗效。方法回顾性分析上海交通大学医学院附属第九人民医院耳鼻咽喉科2016年1月~2017年6月由同一术者经迷路径路手术治疗的72例听神经瘤患者的临床资料,包括术中对颈静脉球的处理和效果。结果72例患者中颈静脉球高位的出现率为29.2%（21例）。术中所有颈静脉球均予清楚暴露。为充分显露桥小脑角,降低50例颈静脉球的高度,其中颈静脉球破裂4例,均为高位颈静脉球（3例使用双极电凝止血,1例通过止血纱布和骨蜡填塞止血）。肿瘤直径为（2.4±1.5）cm,手术全切70例,次全切除2例。术后面神经解剖及功能保留72例,均未出现后组脑神经功能异常。术后一年随访复查MRI未见肿瘤复发,面神经功能HB-I~II 66例（91.7%）,HB-III~IV 6例（8.3%）。结论经迷路径路手术中恰当处理颈静脉球,可充分显露桥小脑角,同时降低颈静脉球破裂和误伤后组脑神经的风险。     

Cochlear implantation in a patient with bilateral deep brain stimulators

OBJECTIVE: We report the case of a patient successfully implanted with a Nucleus Contour cochlear implant after placement of a deep brain stimulator for Parkinson disease. METHODS: The authors conducted a case report and literature review. RESULTS: Successful hookup and mapping of the device was performed 1 month after implantation without evidence of aberrant activity of the deep brain stimulators. CONCLUSIONS: To our knowledge, this is the first reported case of successful implantation of both a cochlear implant and a deep brain stimulator in the same patient. We have outlined one approach to avoiding detrimental interactions between cochlear implant and deep brain stimulator devices.     

Cochlear implantation in children with cochlear nerve deficiency

Objective

The aim of this study was to report on auditory performance after cochlear implantation in children with cochlear nerve deficiency.

Methods

A retrospective case review was performed. Five patients with pre-lingual profound sensorineural hearing loss implanted in an ear with cochlear nerve deficiency participated in the study. Postoperative auditory and speech performance was assessed using warble tone average threshold with cochlear implant, speech perception categories, and speech intelligibility ratings. All patients underwent high resolution computed tomography and magnetic resonance imaging.

Results

According to Govaerts classification, three children had a type IIb and two a type IIa cochlear nerve deficiency. Preoperatively, four patients were placed into speech perception category 1 and one into category 2. All patients had an improvement in hearing threshold with the cochlear implant. Despite this, at the last follow-up (range 18–81 months, average 45 months), only one girl benefited from cochlear implantation; she moved from speech perception category 2 to 6 and developed spoken language. Another child developed closed set speech perception and had connected speech that was unintelligible. The other 3 children showed little benefit from the cochlear implant and obtained only an improved access to environmental sounds and improved lipreading skills. None of these 4 children developed a spoken language, but they were all full-time users of their implants.

Conclusions

The outcomes of cochlear implantation in these five children with cochlear nerve deficiency are extremely variable, ranging from sporadic cases in which open set speech perception and acquisition of a spoken language are achieved, to most cases in which only an improved access to environmental sound develops. Regardless of these limited outcomes, all patients in our series use their device on a daily basis and derive benefits in everyday life. In our opinion, cochlear implantation can be a viable option in children with cochlear nerve deficiency, but careful counseling to the family on possible restricted benefit is needed.     

Bilateral acoustic neuromas

This article reviews 12 patients with bilateral acoustic neuromas. The sex incidence was equal and the mean age at diagnosis was 26.2 years. The family history was positive in nine of the patients. Five patients have had incomplete surgical removal of acoustic neuromas on both sides. Two of them are completely deaf and the other three have severe sensorineural hearing loss in one ear and no hearing in the other ear. In five patients the tumour on one side has been operated on and the other side is being observed with at least short-term preservation of good hearing. The remaining two patients died of intra-cranial complications, one of them post-operatively. Four patients developed facial palsy immediately following surgery and one developed facial weakness 6 months after surgery. Guidelines are discussed for the care of these patients including the timing of surgery and alternative treatment options (observation, radio-surgery adn chemotherapy). This is essentially a group of young individuals who have had multiple operations for bilateral acoustic tumours and associated manifestations and for whom the disease and the sequelae of treatment can be tragic.     

Cochlear implantation in deaf infants

OBJECTIVES: With the application of universal newborn hearing screening programs, a large pool of newly identified deaf infants has been identified. The benefits of early intervention with cochlear implants (CI) is being explored. Mounting evidence suggests that age at implantation is a strong predictor of language outcomes. However, new behavioral procedures are needed to measure speech and language skills during infancy. Also, procedures are needed to analyze the speech input to young CI recipients. STUDY DESIGN: Cohort-sequential. METHODS: Thirteen infants with profound hearing loss who were implanted between the ages of 6 to 12 months of age participated in this study. Eight participated in two new behavioral methodologies: 1) the visual habituation procedure to assess their discrimination of speech sounds; 2) the preferential looking paradigm to assess their ability to learn associations between speech sounds and objects. Older implanted infants and normal-hearing infants were also tested for comparison. The pitch of mothers' speech to infants was analyzed. RESULTS: Patterns of looking times for the very early implanted infants were similar to those of normal hearing infants. Mothers' speech to infants with CIs was similar in pitch to normal-hearing infants who had the same duration of experience with sounds. CONCLUSIONS: No surgical or anesthetic complications occurred in this group of infants, and the pattern of listening skill development mirrors that seen in normal-hearing infants. Mothers adjust their speech to suit the listening experience of their infants.     

Cranioplasty in acoustic neuroma surgery

OBJECTIVES: To measure the incidence of postoperative headaches after retrosigmoid resections of acoustic neuromas and to evaluate the impact of cranioplasty on the prevention and management of these headaches. STUDY DESIGN: A prospective evaluation was performed on 30 consecutive patients who underwent a cranioplasty after retrosigmoid excision of their acoustic neuroma. The results were compared with 30 historical control patients who underwent the same procedure but did not have reconstruction with a cranioplasty. The patients were evaluated by review of office records and via telephone questionnaire. METHODS: One group of patients (30 patients) had no cranioplasty, and the other group of 30 patients had primary reconstruction with a titanium mesh-acrylic cranioplasty. All 60 patients were asked to report on the duration and severity of their headaches by means of a standard questionnaire, grading their symptoms on a scale of 1 to 4. The data were subjected to chi2 and Student t test statistical analyses. RESULTS: New-onset, postoperative headaches occurred in 27% of patients, 23% in the cranioplasty group compared with 30% in the group without cranioplasty (a difference that was not statistically significant [P = .158]). However, there was a statistically significant difference in the severity of the headaches (P<.03). The headaches in the cranioplasty group were less severe and were not disabling. There were no complications, infections, or extrusions related to the cranioplasty. CONCLUSIONS: Cranioplasty has not been able to eliminate postoperative headaches. However, the use of cranioplasty has significantly decreased the severity of postoperative headaches after retrosigmoid excision of acoustic neuromas.     

大型听神经瘤的显微手术技巧及面神经保护

目的探讨大型听神经瘤的显微手术技巧、效果及术中面神经的保护。方法回顾性分析解放军总医院耳鼻咽喉头颈外科2010年1月~2010年12月收治的采用显微外科手术治疗30例大型听神经瘤患者的临床资料。其中男性18例,女性12例;年龄19～71岁,平均39.6±4.2岁;病程3个月～2年。主要临床表现为桥小脑角综合征和颅内压增高征,首发症状表现为耳鸣、听力下降12例,头痛、恶心、呕吐10例,行走不稳4例,面部麻木7例,三叉神经痛2例,面瘫6例。30例术中均行面神经监测,显微镜下切除肿瘤,术毕刺激面神经的脑干端对术后面神经功能进行预测。结果本组30例大型听神经瘤全切除28例,次全切除1例,部分切除1例。术中面神经完整保留29例(96.67%),无死亡病例。肿瘤切除后,面神经刺激阈值的大小与术后面神经功能存在明显的相关性。刺激阈值越小,术后面神经功能越好。结论熟练地采用显微外科技术选择合适的手术入路可明显提高肿瘤的全切除率和面神经的解剖及功能保留率。手术入路的正确选择,娴熟的显微外科操作技术,术中应用面神经监测技术,能有效地保护桥小脑角周围的重要结构及面神经功能,并可预测术后面神经功能。     

Suboccipital surgery for acoustic neuroma

A retrospective study was performed on 106 consecutive patients with an acoustic neuroma who underwent suboccipital surgery for the first time between 1980 and 1992. Complete follow-up data were available for all the patients, including regular imaging up to 1 January 1994. Incomplete removal of the tumours was chosen in preference to radical surgery in a large proportion of the patients, to avoid the risk of postoperative morbidity. The recurrence rate in this series was 20%. Comparison of the results of suboccipital surgery to those obtained using other surgical approaches, while taking the tumour size into consideration, showed that better results can be obtained after total removal of the tumour without any additional risk to post-operative facial nerve function. The long-term results of subtotal removal using the suboccipital approach were disappointing. It is therefore necessary to review the indications for non-radical surgery in patients with an acoustic neuroma.     

Cochlear implantation in cochlear otosclerosis

OBJECTIVES/HYPOTHESIS: The objective was to correlate implant performance in cochlear otosclerosis to 1) matched control samples, 2) severity of otic capsule involvement, 3) prior ipsilateral surgery, and 4) programming issues. STUDY DESIGN: Retrospective case controlled study. METHODS: Study cohort comprised 30 individuals. Diagnosis was based on prior ear surgery (stapedectomy [n = 18] or fenestration [n = 2]) and/or pathognomonic radiological findings. High-resolution computed tomography images of the temporal bones were assessed by two radiologists and graded (range, 0-3) for the extent of otosclerosis. Operative records were reviewed. Performance, programming visits, and the number of electrode deactivations at 6 months and at 1 year after implantation were determined for the individuals with otosclerosis and compared with a group of matched control subjects. A within-group comparison correlating severity of otosclerosis to the above was carried out. RESULTS: Implant performance in individuals with cochlear otosclerosis was not significantly different from those without. Previous surgery on the side of implantation did not alter performance. Programming difficulty as reflected in the number of visits and electrode deactivation for sound quality reasons were comparable. Deactivation for facial nerve stimulation occurred exclusively in otosclerotics with the most severe radiological disease (grade 3) and was only with non-modiolar hugging electrodes (n = 5). There was no observed difference between the radiological extent of otosclerosis and implant performance. CONCLUSION: Individuals with severe otosclerosis considering cochlear implantation can be counseled to expect similar benefit to those without, regardless of whether prior surgery occurred on the side of implantation or of severity of otic capsule involvement. There is a significant risk of facial nerve stimulation in otosclerotics with grade 3 disease.     

Cochlear function following implantation with a full electrode array

Abstract

Objectives: Clinicians traditionally advise patients that implantation with a conventional full cochlear implant array will lead to loss of any remaining hearing in the implanted ear. We sought to assess the extent to which ‘standard’ insertion of a full electrode array affects cochlear function.

Methods: Air conduction pure tone audiometry was performed as part of the routine 6-month postimplantation audiological assessment for 81 adult patients who preoperatively had identifiable pure tone thresholds. All patients were implanted with the nucleus CI24 device, with complete insertion of a straight array in 68 and a contour array in 13 patients. A separate cochleostomy was fashioned anterior to the round window using a 1 mm diamond burr, and the array inserted without lubrication. The operating surgeon was blinded to the inclusion of patients in this study at the time of surgery.

Results: Of 81 patients, 58 preserved some residual hearing at 6 months. The rate of preservation of hearing was higher in the low frequencies. At 500 Hz 77 patients had an identifiable preoperative pure tone threshold, still identifiable postoperatively in 48. At 4 kHz only 25 patients had an identifiable preoperative threshold, preserved in 9, and at 8 kHz 6 of 13 patients still had identifiable pure tone thresholds postoperatively.

There was no correlation between the depth of insertion and hearing preservation, both groups having a mean of 5 stiffening rings inserted in addition to the 22 active electrodes.

The mean deterioration in threshold in those who had residual hearing was 15 dB at 500 Hz, and in 29 patients the deterioration in the threshold was less than 15 dB.

Conclusion: Insertion of a full conventional electrode array is not as damaging to cochlear function as often assumed. Residual low-frequency hearing may be preserved in approximately two-thirds of patients 6 months postoperatively. This study supports our counselling patients that despite the delicate nature of the inner ear there is a significant chance that their air conduction hearing will not be lost.     

内听道狭窄的人工耳蜗植入术效果观察并文献复习

摘要：目的通过观察一例内听道狭窄患者人工耳蜗植入术后的远期康复效果,结合文献复习探讨该类畸形的手术选择指标。方法收集患儿术前听力学资料以及颞骨薄层CT资料,分别于术后半年、2年、4年时进行声场测试、MAIS量表评分、言语识别率测试分析患者康复疗效。并以内听道狭窄、蜗神经管狭窄、蜗神经孔狭窄以及蜗神经发育不良为关键词搜索与人工耳蜗康复的相关文献。结果半年时声场测试500、1 000、2 000、4 000 Hz分别为35、40、40、45 dBHL,2年时MAIS量表评分24分,4年时言语识别率80%,患儿于术后3年时言语理解能力进步明显,康复效果优于文献搜索结果。结论存在内听道狭窄的患者,人工耳蜗植入前对影像学及听力测试结果的综合分析非常重要,选择耳蜗神经发育相对较好侧以及助听效果较好侧手术,同时需坚持术后康复治疗。