听神经瘤手术听力保留的进展

随着影像学技术的发展，尤其是磁共振成像（magnetic resonance imaging，MRI）的临床应用，越来越多没有听力损失的听神经瘤患者被发现，促进了保留听力的听神经瘤手术的发展。听力保留成为继肿瘤全切除和保存面神经功能之后的第三大手术重点。     

加强前庭神经鞘瘤手术听力保留研究

随着显微外科技术、神经电生理监测及神经影像相关技术的发展,前庭神经鞘瘤的治疗目标已经从挽救患者生命转变为神经功能的保留。近年来,前庭神经鞘瘤全切除和保留面神经功能已达到相对稳定水平,听力保留成为继二者后研究热点。本文就手术治疗前庭神经鞘瘤听力保留的现状及相关进展作简要介绍,以期鼓励更多相关研究,促进听力保留工作的进展。     

听神经瘤分期及治疗效果分析

目的探讨听神经瘤分期方法及其与手术效果的关系。方法回顾分析1999～2003年收治的109例听神经瘤病例,按肿瘤大小分为1～5期,3例采用观察方法,106例分别采用扩大迷路进路、乙状窦后进路及颅中窝进路等手术治疗,根据肿瘤切除程度、面神经功能保留程度、听力保留程度等评估手术结果。结果肿瘤全切率为95％(101／106);面神经保留率96％（102／106),迷路进路或扩大迷路进路患者面神经功能优良率(1～2级)为56％,可接受率(1～4级)为86％：听力保存率为42％。结论听神经瘤的统一分期可以帮助选择治疗方案、评估手术效果,对临床治疗工作有重要指导意义。     

听神经瘤治疗策略和手术效果的研究——附594例报告

目的探讨听神经瘤手术效果及治疗策略选择。方法回顾性分析2001年1月至2010年12月共594例听神经瘤患者所采用治疗策略及其中461例手术效果。结果 594例患者中,管内/小型、中/中大型、大/巨型听神经瘤分别占25.6%、55.1%和19.3%,随访观察、立体定向放疗和手术率分别为25.3%、6.9%、77.6%。461例手术患者中,肿瘤全切、近全切、次全切率分别为95.9%、3.0%、1.1%,面神经解剖保留94.4%,术后短期和长期面神经功能良好率为69.8%和79.0%,术后听力保留率41.4%,听力良好率23.4%,手术死亡率0.2%,后组颅神经麻痹和脑脊液漏率分别为3.9%和3.3%,复发率为2.2%。结论手术仍为听神经瘤主要治疗策略,其效果令人满意,而听神经瘤早期诊断将促进治疗策略的改变。     

听神经瘤手术的听力保存

目的探讨听神经瘤手术的听力保留。方法回顾分析2000年至2012年在解放军总医院耳鼻喉头颈外科经听力保留手术切除听神经瘤的病例。结果 32例患者中,术后成功保留听力者为43.8%(14/32)。其中,听功能A级者5例,B级者5例,C级者3例,D级者1例。结论保留听力的听神经瘤切除术可取得相当的听力保存率,是可选择的听神经瘤治疗方法。     

经迷路进路与经耳囊进路在听神经瘤手术中的应用比较

听神经瘤的发病率居颅内肿瘤第三位,是桥小脑角最常见的肿瘤[1].有关听神经瘤的治疗方式包括密切随访、放射治疗、手术治疗等.多数耳外科、脑外科专家认为手术切除肿瘤为首选治疗方式.具体手术方式分为牺牲听力(经迷路进路和经耳囊进路等)和保留听力(颅中窝进路和乙状窦后进路)两大类,而肿瘤的大小、位置及残余听力是选择手术进路的主要参考因素[2].评估手术效果包括降低死亡率、提高全切率、提高面神经功能保留率和听神经功能保留率.     

伴有突发性聋的听神经瘤术后听力改善

听神经肿瘤切除术应注意保存听力及面神经功能，随MRI强化扫描技术的发展，小听神经瘤的诊断率及术后保留听力的可能性都在增加，但罕见术后患者能获听力改进的报道，该作者认为即使是很小的听神经瘤也有引起突发性耳聋的可能，因此，将突发性聋做为听神经瘤的初始症状对于小听神经瘤的诊断很有意义，小听神经痛，尤其伴有突发性聋者，如能早期手术则听力保留的可能性更大。甚至有些患者在术后2～3月时听力还可提高。因此在应用MRI的时代，其手术不应仅限于保存听力，而应着眼于提高听力。总结3例听神经瘤病例，术前均有突发性耳聋，伴不…     

听神经瘤手术的听力保护

探讨听神经瘤手术的听力保护.方法报告两例经乙状窦后进路、内镜辅助和术中用CAP和ABR连续适时监测下切除听神经瘤的结果.结果例1 MRI示内听道口外瘤体直径约1.5cm,术前语频纯音听阈平均在30dB,能引出ABR各波.术中以ABR适时监测,完全切除瘤体后仍可引出清楚的ABR Ⅰ、Ⅲ、Ⅴ波,术后无面瘫.术后7个月复诊,纯音听阚及ABR波间期恢复术前水平.例2为双侧听神经瘤.MRI示左右听神经瘤直径分别为4cm和5cm.一侧肿瘤切除后间隔4个月行另一侧听神经瘤切除术.为保留第二次手术耳听力,术中用CAP监测.术中虽未能保留蜗神经,但切除肿瘤后仍可记录到CAP.结论听神经瘤手术中的CAP监测结果无法评判术后能否保留听力,而ABR则能够及时反映听神经及其通路的功能状态,肿瘤切除后引出ABR Ⅰ、Ⅲ、Ⅴ波可有望保存术前听力.     

9例听神经瘤经立体定位放射外科治疗后的听力结果

由于解剖知识的积累和技术操作方面的改进,有些技术精湛的耳科及神经外科医生,不但能安全切除听神经瘤,而且对一些中小型肿瘤病人。还能保存面神经及听力功能,如House(1968)在24例中小型肿瘤患者中,14例保存了面神经功能,7例保存了听力。自显微外科开展以来,Yasargil等(1977)及DiTullio等(1978)分别报告了30和34例中、小型听神经瘤,80％保存了面神经功能;2例保存了听力。虽然如此,开颅     

听神经瘤手术的听力保存技术

目的 探索听神经瘤切除术中保留术前残余听力的可能性,以及评价术中动态听力监测和耳内镜技术对听力保护的效果.方法 2003年至2007年7月共收治听神经瘤手术患者138例,对术前有残余听力18例(18耳)施行术中连续听力监测.男6例,女12例;左12耳,右6耳;年龄14～64岁;15例为单发的听神经鞘瘤,3例为神经纤维瘤病Ⅱ型.MRI测得肿瘤最大直径在12～33 min,中位数19.5 min.均采用经乙状窦后入路,10耳辅以耳内镜下手术.18例均行听性脑干反应(ABR)及耳蜗电图术中连续听力监测;术中常规监测面神经功能.术后随访时间为6个月～2.5年,以最后一次听力结果为准.术前及术后听力评价标准采用1995年美国耳鼻咽喉头颈外科学会分级法.结果 手术全切16例,大部分切除2例(均为神经纤维瘤病Ⅱ型).无死亡病例,术后均恢复顺利,无脑脊液漏,无皮下血肿等术后并发症.18例术前均无面神经麻痹,术中面神经均得以保存,解剖结构连续完整.术后7 d面神经功能Ⅰ～Ⅱ级占50.0%(9/18);术后6个月面神经功能Ⅰ～Ⅱ级占88.9%(16/18).18耳中11耳术后听力得以保存(61.1%),术后听力A级4耳,B级4耳,C级2耳,D级1耳.术前肿瘤>20 min者共5耳仅2耳保存听力,<20 mm者共13耳术后听力保存9耳(69.2%).耳内镜辅助下手术10耳,听力保存8耳(80.0%).术中监测发现,手术过程中当磨钻内耳道后唇、内耳道口附近处牵拉或电凝止血,尤其是夹持内听动脉、处理内耳道处肿瘤及夹持或电凝肿瘤表面最内层蛛网膜血管时,对ABR和耳蜗电图波形影响很大.结论 对术前有良好听力的听神经瘤患者应在术中辅以实时动态听力监测,并结合术中耳内镜技术进行听力保护,术后能够获得较好的听力保存效果.听神经瘤表面蛛网膜的保留及其血供状况对保留听力起重要作用,而内听动脉的损伤是术后听觉丧失的最主要原因.     

Outcome on hearing and facial nerve function in microsurgical treatment of small vestibular schwannoma via the middle cranial fossa approach

Encouraging results regarding hearing preservation and facial nerve function as well as increasing understanding of the natural behaviour of vestibular schwannomas have led to the recommendation of an early treatment in small VS. The aim of the present study was to evaluate current data on functional outcome of patients with small VS treated by middle cranial fossa (MCF) approach. A retrospective chart study of all cases treated by MCF approach between October 2007 and September 2011 was performed. Records were analyzed regarding demographical data, tumor size, hearing status, vestibular function and facial nerve function. Facial nerve function was classified according to the House–Brackmann scale (HB). Hearing status was classified according to the American Association of Otolaryngology-Head and Neck Surgery (AAO-HNS) and a modified classification of Gardner and Robertson (GR). Eighty-nine patients were included in the study; 41 % of VS was classified as intracanalicular (stage 1) and 59 % as stage 2. From 65 patients with a preoperative hearing status according to AAO-HNS A or B, 74 % still presented with A or B after surgery. Using a modified GR classification, from 70 patients categorized as class I or II prior to surgery, 70 % were still class I or II. Looking to the facial nerve function 1 week after surgery, 82 % of patients presented with HB 1 or 2. Three to twelve months later, 96 % demonstrated HB 1 or 2. A persisting facial palsy was recorded in four patients. Preoperative hearing status was evaluated as a prognostic factor for postoperative hearing, whereas no influence was detected in ABR, vestibular function and tumor length. Early diagnosis of small VS due to high-sensitive MRI requires the management of this tumor entity. Natural behaviour of VS in many cases demonstrates an increase of tumor size over time with deterioration of hearing status. The presented data underline the recommendation of an early surgical treatment in small VS as a valuable option for hearing preservation in the therapy of VS.     

ADVANCES IN SURGICAL TREATMENT OF ACOUSTIC NEUROMA

Acoustic Neuroma (AN) arises from the eighth cranial nerve. It primarily involves the vestibular branch of the nerve and is therefore also called vestibular schwannoma(VS). To the date, diagnosis and surgical treatment of AN have advanced significantly. Along with advances in audiology and imaging technologies, cases of diagnosed AN have been increasing, making it a common     

Management strategies in neurofibromatosis type 2

The objective of this study was to review the experience of the Neurotology and Skull Base Surgery Unit of Addenbrooke's Hospital in Cambridge, England, in the management of patients with neurofibromatosis type 2 (NF2). This was a retrospective review of the institution's series conducted at a neurotological tertiary referral centre. Over a 17-year period (1984-2001), 35 patients with NF2 were managed. These patients presented with multiple cranio-spinal neoplasms, including 62 cerebellopontine angle tumours of which 59 were vestibular schwannomas (nine patients with unilateral tumours and 25 patients with bilateral tumours). Clinical presentation, diagnosis and patient management were reviewed. The outcome parameters measured were tumour progression, the incidence of complications (hearing deterioration and facial nerve palsy) and the need for secondary intervention. Five vestibular schwannomas were treated with stereotactic radiosurgery (gamma-knife), all of which showed evidence of progression in size and/or deterioration in hearing. Thirty-one VS were conservatively treated with annual surveillance. In nine cases, the tumours had a follow-up shorter than 6 months and were therefore excluded from the results. In 13 cases the VS did not progress in size, and the hearing remained stable, while in the remaining nine cases, tumour progression was evident. In fifteen cases, surgery was performed at the authors' institution. In 11 cases a translabyrinthine approach was adopted, and in the remaining four cases a retrosigmoid approach was preferred. In all these cases, tumour removal was total and facial nerve function was House-Brackmann grade I-III in 55%. Successful hearing preservation was elusive in those patients in whom a hearing preservation approach was attempted. NF2 remains an extremely challenging disorder for the neurotologist and the patient alike. Early diagnosis offers distinct advantages to the patients, their families and the community at large. Of the treatment modalities, surgery unequivocally offers the most superior tumour control. Hearing preservation remains a challenge in these patients, but is optimised by the early detection of tumours in the NF2 patient.     

10年单中心听神经瘤患者手术治疗回顾性研究

目的回顾性分析本中心手术治疗的听神经瘤患者,对临床特点、术前影像学、手术切除率、术后神经功能状态及术后并发症进行统计分析,并借此探讨听神经瘤患者的规范外科治疗策略。方法:回顾性分析自2007年6月至2017年6月于本中心接受外科治疗的单侧听神经瘤患者,统计分析患者一般资料,肿瘤大小、手术时间,术中出血量、肿瘤切除率、神经功能评估、术前(后)听力学检查及术后并发症等数据,并对上述各项数据进行多元逻辑回归分析。探讨肿瘤大小与手术时间、术中出血量及术后并发症之间的关系。结果:根据纳入排除标准,共有557名患者进入本研究,手术均采用枕下乙状窦后入路,患者平均年龄45.8±10.8岁;其中男性230例(37.7%);肿瘤直径≥3cm者468例(84.0%);平均手术时间5.2±1.8小时;术中出血量337±145ml;肿瘤达全切者513例(92.1%),次全切者44例(7.9%);518例患者达到术中面神经解剖保留(93.0%);术后House-Brackmann分级评估面神经功能Ⅰ-Ⅲ级者471例(84.6%);术前听力可用者41例,术后听力可用者12例(29.3%)。术后发生脑脊液漏者16例(2.9%),发生术侧面部麻木者12例(2.2%),出现复视者18例(3.2%),出现后组颅神经麻痹症状者15例(2.7%),术后颅内出血者5例(0.9%)。校正多元逻辑回归分析结果显示,肿瘤大小与手术时间、术中出血量、术后面瘫及复视发生率之间呈正相关关系(P<0.05),当肿瘤最大直径>5cm时,术中出血量显著增加(P<0.05)。结论:单侧听神经瘤患者手术治疗的难点是术中神经功能的保护。减少手术操作的机械损伤、运用术中神经电生理监测技术对提高治疗效果十分关键。肿瘤大小与手术时间、术中出血量及术后神经功能障碍发生率呈正相关关系。     

What Really Decides the Facial Function of Vestibular Schwannoma Surgery?

Objectives

To find the main cause of facial nerve dysfunction in vestibular schwannoma (VS) surgery and review the prognosis of facial function in relation to tumor size, preoperative facial function and surgical approach.

Methods

We reviewed the surgical outcome of 134 patients with VS treated in our department between 1994 and 2008. All patients included in the study had postoperative facial paralysis after surgical management of their VS. There were 14 women and 7 men. The mean age was 48.5 years, with a mean follow-up period of 57 months.

Results

Twenty-one patients (sustained facial palsy, 4; newly developed facial palsy, 17) had facial nerve paralysis after surgery: ten patients in large VS and eleven patients in small VS. In large VS group, 4 patients had facial nerve function of HB grade II, 3 patients had HB grade III, and 3 patients had HB grade IV. In small VS group, 9 patients had HB grade II and 2 patients had HB grade IV. Middle cranial fossa approach rather than translabyrinthine approach for the preservation of hearing, led to facial nerve deterioration and the patients who had facial nerve paralysis perioperatively, had resulted in permanent facial paralysis.

Conclusion

The tumor size in VS is certainly one of the most important prognostic factors. However, VS tumor size alone should not be considered a unique prognostic indicator. The surgical approach used, which may be related to tumor size, based on the surgeon''s experience, can be a deciding factor, and the status of the facial nerve injured by the tumor can influence postoperative facial nerve function.     

Impact of Tumor Size on Hearing Outcome and Facial Function with the Middle Fossa Approach for Acoustic Neuroma: a Meta-analytic Study

Objective--The purpose of this study was to review the English language literature concerning the effect of tumor size on hearing outcome and facial function after the middle fossa approach for acoustic neuroma in a large patient population. Material and Methods--The literature search identified a total of 11 studies reporting hearing outcome and facial function for a given tumor size. There were 1073 and 797 cases available for the analysis of hearing outcome and facial function, respectively. These cases were subdivided based on the way in which tumor size was measured: category 1 considered only the extracanalicular portion of the tumor; and category 2 considered the largest diameter of the tumor. In category 1, hearing and facial results were regrouped based on tumor size as follows: intracanalicular (IC) tumors; 1-9 mm tumors; 10-20 mm tumors; and a combined group of < 0.5 mm tumors, including IC tumors. In category 2, tumors were subdivided into 2 groups: those < 10 mm in diameter; and those 10-20 mm in diameter. In each category, tumor size groups were compared using the χ² test in terms of the rate of functional hearing preservation and good facial function. Results--In category 1, analysis of the rate of functional hearing preservation showed that IC tumors compared favorably with the 1-9 mm and 10-19 mm tumors (56.9% vs 45.6%, p = 0.016; and 56.9% vs 32.3%, p < 0.001, respectively). The IC tumor group had the best rate of good facial function, followed by the 1-9 mm and 10-19 mm tumors (98.9% vs 93.9%, p = 0.007: and 98.9% vs 85.6%, p < 0.001, respectively). In category 2, rates of functional hearing preservation and good facial function were almost the same for tumors < 10 mm in diameter and those 10-20 mm in diameter (p > 0.05). Conclusion--The meta-analysis revealed that tumor size is an important variable determining hearing outcome and facial function. Inclusion of the IC portion of a tumor in the tumor size measurement apparently hampered the statistical power of the study, leading to an overestimation of the size of IC tumors.     

Nerve of origin, tumor size, hearing preservation, and facial nerve outcomes in 359 vestibular schwannoma resections at a tertiary care academic center

Objective: To determine nerve of origin, tumor size, hearing preservation rates, and facial nerve outcomes in a retrospective cohort study of patients undergoing translabyrinthine (TL), middle cranial fossa (MCF), and retrosigmoid/suboccipital (SO) approaches to vestibular schwannomas (VS). Study Design: Retrospective. Methods: Chart review. Results: Patient charts from 231 TL, 70 MCF, 53 SO, and 5 combined TL/SO procedures for VS were evaluated in 356 patients. The inferior vestibular nerve (IVN) was the nerve of origin in 84 of 359 cases (23.3%), while the superior vestibular nerve (SVN) was the nerve of origin in 36 patients (10%). In 239 of 359 cases (66.6%), the nerve of origin was not identified. Forty patients undergoing hearing preservation surgery had hearing results and nerve of origin data available for review. Functional hearing (<50dB PTA and >50% speech discrimination) was preserved in 10 of 15 patients (75%) with SVN tumors, while only 7 of 25 patients (28%) with IVN tumors retained functional hearing. Facial nerve outcomes and nerve of origin were recorded simultaneously in 109 patients. Seventy‐one of 74 patients (95%) patients with IVN tumors achieved a House‐Brackmann (HB) grade I–III, while 35 of 35 patients (100%) with SVN tumors retained HB I–III facial function. Looking at tumor size versus hearing preservation, functional hearing was preserved in 22 of 49 patients (45%) with <1‐cm tumors, and 4 of 20 patients (20%) with 1‐ to 1.5‐cm tumors. For all cases with documented facial nerve function, HB I–III were achieved in 96% of SO, 94% of MCF, and 88% of TL procedures. Conclusions: Our retrospective data indicated that IVN tumors were twice as common as SVN tumors. The nerve of origin did not affect facial nerve outcomes but did impact hearing preservation rates. Patients with tumors <1 cm in size had the best chance for hearing preservation. Overall facial nerve preservation was excellent with >90% achieving HB 1 to 3 function at final follow‐up.     

Hearing preservation using combined monitoring of extra-tympanic electrocochleography and auditory brainstem responses during acoustic neuroma surgery

The aim of this study was to evaluate the efficacy of an intraoperative monitoring hearing preservation strategy that includes simultaneous recordings of an auditory brainstem response (ABR) and non-invasive electrocochleography (ECochG). The combined ABR and tympanic membrane (TM) ECochG testing was performed in 74 patients undergoing acoustic neuroma (AN) surgery. In addition, EMG recordings were conducted to monitor the facial nerve function. Hearing was preserved in 19 of the 30 patients with residual hearing prior to surgery (63%), and facial nerve function was maintained in 89% of the patients. In most cases, the presence of both auditory brainstem and TM-ECochG responses at the end of surgery was associated with preservation of postoperative functional hearing; however, eight patients had a TM-ECochG response with a complete loss of the ABR, pointing to deafferentation of the auditory nerve. Tumour size and preoperative hearing thresholds significantly affected the postoperative hearing. The TM-ECochG response yielded large reproducible responses, which, in some patients, was the only way to monitor the auditory function. This auditory monitoring approach offers a valuable auditory tool that helps to improve the hearing preservation during AN surgery.     

The diagnostic significance of the 3D-reconstructed MRI in vestibular schwannoma surgery: prediction of tumor origin

In hearing preservation surgery for the treatment of vestibular schwannoma (VS), one of the important factors is the determination of the origin of VS. In this study, we investigated the diagnostic significance of using an MRI obtained by the three-dimensional Fourier transform fast spin-echo technique (3D-reconstructed MRI) in order to determine the origin of VS. The subjects consisted of 20 patients with mainly intra-canalicular sized VS who underwent tumor removal at our hospital. The origin of VS was determined from the 3D-reconstructed MRI findings and the results of the caloric test. These findings were then compared with the surgical findings. In 15 out of 20 patients, the MRI findings closely corresponded to the surgical ones, while the origin of VS hardly could be detected when a tumor filled up to the fundus acoustics on the MRI findings of the axial sections. On the other hand, 6 out of 15 patients (40%) whose tumor originated from the inferior vestibular nerve showed canal paresis. In conclusion, 3D-reconstructed MRI is considered to be helpful in obtaining more precise information regarding the origin of VS compared to the caloric test. Received: 18 May 2001 / Accepted: 5 October 2001