Clinical experience with gamma knife stereotactic radiosurgery in the management of vestibular schwannomas secondary to type 2 neurofibromatosis

OBJECTIVE: To evaluate the results of stereotactic radiosurgery treating vestibular schwannomas secondary to type 2 neurofibromatosis. METHODS: A retrospective review of 122 type 2 neurofibromatosis vestibular schwannomas consecutively treated in 96 patients. Tumour control was assessed by recourse to surgical intervention, by serial radiological imaging, and by the calculation of relative growth ratios in patients (n=29) habouring untreated contralateral tumours to act as internal controls. Hearing function was assessed with Gardner-Robertson grades and with averaged pure tone audiogram thresholds. Other complications are detailed. RESULTS: Applying current techniques, eight years after radiosurgery it was estimated that 20% of patients will have undergone surgery for their tumour, 50% will have radiologically controlled tumours, and in 30% there will be some variable concern about tumour control, but up to that time they will have been managed conservatively. Relative growth ratios one and two years after treatment indicate that radiosurgery confers a significant (p=0.01) advantage over the natural history of the disease. Analysis of these ratios beyond two years was precluded by the need to intervene and radiosurgically treat the contralateral control tumours in more than 50% of the cases. This growth control was achieved with 40% of patients retaining their Gardner-Robertson hearing grades three years after treatment, (40% having some deterioration in grade, 20% becoming deaf). Pure tone audiogram results suggest some progressive long term hearing loss, although interpretation of this is difficult. Facial and trigeminal neuropathy occurred in 5% and 2%. CONCLUSIONS: Radiosurgery is a valuable minimally invasive alternative treatment for these tumours. For most patients, it controls growth or defers the need for surgery, or both. There is a price in terms of hearing function, although this may compare favourably with the deafness associated with the natural history of the disease, and with surgery. In deciding on therapy, patients should be aware of this treatment option.     

Gamma knife radiosurgery for intracanalicular acoustic neuromas

In the present study we reviewed our long-term experience with radiosurgery for intracanalicular acoustic neuromas. The study involved 25 patients with unilateral intracanalicular acoustic neuromas. The treatment volume was 0.07 to 0.8 cm(3) (median: 0.27 cm(3)). The marginal radiation dose used for treatment was 12 Gy for all patients. The follow-up period ranged from 36 to 132 months (mean: 89 months). The actuarial rate of tumour growth control at 5 and 10 years after radiosurgery was 96%. Hearing preservation was achieved in 16 patients (64%) and improvement (>20 dB relative to presurgical values) was noted in one patient (4%). No patients experienced post-radiosurgery facial palsy or other cranial nerve deficits. Based on our study and long-term follow-up, radiosurgery can produce high rates of tumour growth control and hearing preservation for intracanalicular acoustic neuromas, and is an alternative to surgical resection given its low level of invasiveness. When determining treatment for intracanalicular acoustic neuromas, the condition's benign natural course and the likelihood of hearing preservation must be taken into account.     

伽玛刀治疗听神经瘤229例疗效分析

[目的]评价伽玛刀治疗听神经瘤的疗效.[方法]采用OUR旋转式伽玛刀治疗229例听神经瘤患者,观察术后病情变化.[结果]本组伽玛刀治疗病例随访6～60个月,其中肿瘤缩小98例,肿瘤体积不变115例,肿瘤增大16例,治疗前存在有用听力病例中38例听力下降;130例患者有用听力得到保留;54例出现患侧面瘫;11例出现三叉神经功能部分受损.[结论]伽玛刀对听神经瘤有较高的肿瘤控制率,并能保留有用听力,对面神经、三又神经损伤小,是小至中等大小听神经瘤可供选择的治疗[方法],及术后残余和复发肿瘤的重要辅助治疗手段.     

伽玛刀治疗听神经瘤疗效分析

目的探讨伽玛刀治疗听神经瘤的疗效。方法连续应用Leksell伽玛刀治疗92例听神经瘤。结果随访12-36个月。肿瘤生长控制率为93.5％（86／92），无死亡及严重并发症发生。在65例可评价病例中，听力保留38例，保留率58.5％。治疗后4～8周8例（8.7％，8.92）出现轻度周围性面瘫，半年后逐渐恢复；6例（6.5％，6.92）出现三叉神经受损症状，表现为面部麻木。6～12个月后恢复。结论伽玛刀治疗听神经瘤安全、有效，患者生存质量高。     

大型听神经瘤的显微手术治疗

目的 探讨显微手术切除大型听神经瘤的入路和方法。方法 经枕下入路显微手术切除大型听神经瘤226例,其中锁孔手术93例。结果 肿瘤全切除193例,次全切除33例。术后死亡1例。术后出现肿瘤部位血肿4例。术中面神经解剖保留205例。177例出院后随访2月~13年,面神经House-Brachmann分级Ⅰ~Ⅲ级143例,Ⅲ级以上34例。结论 枕下入路是显微手术切除大型听神经瘤的有效入路,并能较好地保留面神经功能;强调术中监测,仔细、耐心操作以便保留面神经的功能;当肿瘤与面神经或脑干粘连紧时勿强求肿瘤全切;锁孔手术完全可以达到切除大型听神经瘤要求,损伤小。     

Outcomes of 75 patients over 12 years treated for acoustic neuromas with linear accelerator-based radiosurgery

The aim of this study was to investigate the efficacy of linear accelerator (LINAC)-based radiosurgery in the treatment of acoustic neuromas. In this retrospective study, we enrolled 75 patients with non-neurofibromatosis type 2 acoustic neuromas who were followed-up for more than 5 years. The 75 patients were divided into 3 groups: patients with a newly diagnosed tumor; those with a residual tumor; and those with a recurrent tumor. The average follow-up period was 97.8 months. The overall tumor progression-free rate was 92%, and corresponding rates among those with newly diagnosed tumors was 100%, residual tumors was 84.4%, and recurrent tumors was 92.8% (p = 0.028). Lesion localization using CT scans correlated with a higher tendency for tumor progression than lesion localization using CT–MRI fusion images (15.6% versus 2.4%, respectively). Residual tumors treated with radiosurgery have a higher progression rate, and careful lesion localization using CT–MRI image fusion is required.     

听神经瘤的γ—刀治疗（附119例随访报告）

目的 评价伽玛刀（γ－刀）治疗听神经瘤的疗效。方法 用Leksell B型γ-刀治疗听神经瘤119例,并随访1－5年。扫描定位用1．5Tesla磁共振仪,剂量规划系统为γ-plan4.0版。肿瘤体积0．02－20．8cm^3;周边剂量9－17Gy,平均13Gy;中心剂量18－45Gy,平均32Gy;靶点数2－10个,平均4个。结果 肿瘤体积缩小95例（80％）,其中显效16例（13％,指体积缩小超过75％）,无变化14例（12％）,增大10例（8％）。61例（51％）听力有保存,11例（9％）听力有改善;5例半年后出现面瘫,1列持续5周后消失,2例经再次手术后好转,另有2例有永久面瘫;3例病人出现三叉神经痛,2例为一过性,1例服药好转。结论 γ-刀治疗对听神经瘤具有良好的控制生长作用,尤其适合体积＜6．5cm^3及不宜开颅手术的病人,对颅神经的损伤风险低,是一种安全有效的治疗方法。     

枕下乙状窦后入路锁孔手术切除听神经瘤

目的 探讨枕下乙状窦后入路锁孔手术切除听神经瘤的方法及效果。方法 回顾性分析2016年1月至2018年6月经枕下乙状窦后入路锁孔手术治疗的116例听神经瘤的临床资料,根据术前增强MRI分为中小型听神经瘤组（最大径≤3 cm;83例）和大型听神经瘤组（最大径>3 cm;33例）。结果 中小型听神经瘤组肿瘤全切除率为97.6%（81/83）,面神经解剖保留80例（96.4%）。术后1周面神经功能良好（H-B分级Ⅰ~Ⅱ级）59例（71.1%）。大型听神经瘤组肿瘤全切除率87.9%（29/33）,面神经解剖保留28例（84.8%）,术后1周面神经功能良好18例（54.5%）。结论 对于中小型听神经瘤,采用枕下乙状窦后入路锁孔手术可实现肿瘤完全切除和良好的面神经功能保护。对于大型听神经瘤,在良好体位、充分释放脑脊液、电生理监测等辅助下,采用乙状窦后入路锁孔手术也可实现肿瘤安全满意切除和面神经功能保护。     

126例听神经瘤个体化治疗体会

目的总结连续治疗126例听神经瘤的体会,探讨选择性采用手术或γ-刀治疗听神经瘤的效果。方法对选择性采用手术或γ-刀治疗的126例听神经瘤病例（127个肿瘤,包括1例双侧听神经瘤）进行回顾性分析。结果枕下乙状窦后入路显微手术切除104例,行γ-刀治疗23例（1例双侧听神经瘤行以上两种治疗）。手术全切88例（84.6%）,大部切除14例（13.5%）,术后死亡2例（1.9%）。术后面神经功能保留64例（61.5%）,随访后面神经功能保留73例（70.2%）。γ-刀治疗面神经功能保留7例（30.4%）。结论听神经瘤的治疗应根据症状、体征、肿瘤大小、肿瘤生长情况及患者全身状况,个体化的选择治疗方式。选择性采用手术或γ-刀治疗听神经瘤是一种有效,可行的治疗模式。     

SURGERY OF ACOUSTIC NEUROMAS

Inspired by the works of William House, the authors formed an otoneurosurgical team in order to improve the results after surgery for acoustic neuromas. This paper deals with the preliminary results obtained with the translabyrinthine approach in 13 patients with acoustic neuromas. In 9 patients it was possible to remove the tumor totally with this approach, in 4 patients a second suboccipital operation was necessary to secure total removal. One small, 7 medium and 5 large tumors were encountered. The facial nerve was preserved in 83 per cent of the patients. One patient with a large tumor died after the second suboccipital operation. The relation between size of the tumor and the outcome of the operation is stressed, and in order to reduce the number of large tumors it is suggested that all patients with unilateral hearing loss should be suspected of having a neuroma, until the diagnosis has been disproved. It is concluded that the surgery for acoustic neuromas is otologic-neurosurgical teamwork, and that the treatment should be centralized.     

听神经瘤手术治疗的临床体会

目的 总结104例听神经瘤手术切除的体会，以提高此类手术的治疗效果。方法 经CT或MRI扫描检查确诊，应用显微外科技术，经枕下-乙状窦后入路行肿瘤切除术。结果 肿瘤全切89例（85．58％），次全切和大部切除15例（14．42％）；术后死亡2例（1．92％）。术中面神经解剖保留89例（85．58％），听神经解剖保留25例（24．04％），术后7例（6．73％）听力保存或有所改善。结论 肿瘤大小与肿瘤全切率及面、听神经保留率密切相关。合适的体位，正确的切除方法及较强的功能保护观念，是提高听神经瘤手术疗效的关键。     

伽玛刀治疗听神经瘤(附98例分析)

目的 评价伽玛刀治疗听神经的效果。方法 应用OUR旋转式伽玛刀治疗听神经98例。肿瘤直径512～29．7min．平均18.8mm。采用多个放射中心联合照射，周边等剂量曲线为45％-70％，边缘剂量10-13Gy。结果 81例获14。84个月随访，平均39个月。MRI示41例（50．6％）肿瘤缩小，38例（46.9％）无变化，2例（2．5％）增大；25例（30.9％）肿瘤中心失增强。无面瘫和面部麻木，听力保留率59.2％。结论 伽玛刀对听神经瘤有较高的肿瘤控制率，并能保留有用听力，对面神经、三又神经损伤小，是小至中等大小听神经瘤可供选择的治疗方法，及术后残余和复发肿瘤的重要辅助治疗手段。     

面神经电生理监测在大型听神经瘤术中的应用

目的 探讨大型听神经瘤术中面神经监测对面神经保护及评估术后面神经功能的临床意义。方法回顾性分析我科2007年6月至2010年3月术中行面神经监测的42例大型听神经瘤的临床资料。结果 面神经解剖保留37例(88％),面神经功能保留30例(71％)。术末刺激强度1～3V即引起肌电反应者预后良好;而术末面神经近端与远端波幅之比＜0.3者预后差。结论 大型听神经瘤术中面神经监测可显著降低术后面神经瘫痪的发生率,术末面神经脑干端的刺激强度与面神经功能呈负相关,而面神经近端与远端波幅之比与面神经功能呈正相关。     

Facial nerve function after excision of large acoustic neuromas via the suboccipital retrosigmoid approach.

We review our results for facial nerve preservation in 105 patients with large acoustic neuromas (diameter 4.0 cm or larger) undergoing excision via the suboccipital retrosigmoid approach. Microneurosurgical techniques and facial nerve monitoring were used. Complete tumor removal was achieved in 91 cases (86.7%) and subtotal removal in 14 (13.3%). There were two postoperative deaths (1.9%). The facial nerve was preserved anatomically in 83 (79.1%) patients. Using the House-Brackmann grading system, facial nerve function was assessed immediately after surgery, at the time of discharge and 1 year after surgery. Excellent function (Grades I and II) was present in 41.0%, 41.8%, and 56.7% of patients at each time interval, respectively, with acceptable function (Grade I-IV) in 78.5% (68/87 cases) at follow-up assessment at one year. The suboccipital retrosigmoid approach resulted in good anatomical and functional preservation of the facial nerve during excision of large acoustic neuromas, with minimal other morbidity and low mortality. We recommend this approach for excision of large acoustic neuromas.     

大型听神经瘤常见手术并发症及其相关因素分析

目的探讨枕下乙状窦后入路切除大型听神经瘤术后常见的手术并发症及其相关因素。方法对96例大型听神经瘤患者的临床资料及术后随访结果进行回顾性研究。结果96例大型听神经瘤全切88例,次全切除5例,大部分切除3例。面神经解剖保留率92．7％（89／96）,死亡4例。术后并发症：患侧听力丧失88例,面神经麻痹47例,脑脊液漏8例,颅内积气14例,颅内血肿6例。结论大型听神经瘤术后并发症的发生率与肿瘤的大小及囊性变、手术体位等有关;术者显微技术熟练程度是影响术后并发症的主要因素。     

听神经瘤术中面部肌肉肌电图及BAEP的监测与面听神经功能保留：400例临床研究

目的总结听神经瘤术中监测面部肌肉自发与诱发肌电图和脑干听觉诱发电位（BAEP）的经验,分析术中面、听神经解剖功能保留的方法及影响因素。方法使用美国Nicolet公司生产的Viking—Ⅳ型和Axon公司的Epoch XP型多导术中监测仪,对收治的400例听神经瘤患者进行了术中监测面部肌肉自发与诱发肌电图和BAEP。手术切除肿瘤,术后对患者进行面、听神经功能评估。结果肿瘤全切388例（97．70％）,次全切9例,死亡3例。本组病人面神经解剖保留率为95．97％,功能保留率为91．94％。术后主要并发症包括完全性永久性面瘫11例,面部麻木23例,角膜溃疡18例,耳呜29例,后经颅神经瘫痪28例,轻偏瘫3例,听力完全丧失139例。结论通过面部肌肉肌电图及BAEP的监测,可以准确判断颅神经的位置,最大程度避免颅神经的损伤。术中面部肌肉自发与诱发肌电图和BAEP监测,对听神经瘤外科手术的安全性提供了一定的保障,减少了手术的风险,使用得当可降低手术的致残率,应该成为听神经瘤手术的常规工作。     

手术治疗复发听神经瘤的临床分析

目的 研究复发听神经瘤的手术方法和疗效。方法 回顾性分析27例复发听神经瘤病人的临床诊治资料。手术方法采用原手术切口枕下乙状窦后入路25例，颞下入路2例；术中使用内窥镜辅助切除肿瘤10例。结果 27例再手术病人中肿瘤全切除21例，次全切除4例，大部分切除2例。无死亡病例。12例在手术后面神经得到解剖保留。有2例手术后出现伤口脑脊液漏，1例出现脑脊液耳漏，经腰穿置管引流等保守治疗后好转。2例于半年内复诊时仍伴有明显脑积水，行分流手术后症状改善。术后按GOS评估，15例患者正常生活和工作，8例可做轻量工作或生活能自理，4例需要他人照顾。结论 虽然复发听神经瘤与面听神经、脑干等结构有不同程度的粘连。但大多数患者经显微手术治疗可取得良好的效果。     

大型囊性听神经瘤的临床特点及显微手术治疗

目的 探讨大型囊性听神经瘤的临床特征,总结显微手术治疗经验.方法 对经显微手术治疗的24例大型囊性及50例大型实性听神经瘤进行回顾性对比分析.结果 囊性肿瘤全切17例(71%),次全切6例(25%),大部切除1例(4%),面神经解剖保留20例(83%).实性肿瘤全切45例(90%),次全切5例(10%),面神经解剖保留45例(90%).囊性肿瘤首发症状多不典型,病程短,脑积水发生率高.结论 大型囊性听神经瘤发展迅速,应及时手术治疗.应用显微外科技术,对与神经组织紧密粘连的肿瘤,采取次全切除的策略,有助于面神经的保护,提高临床效果.     

Multidisciplinary treatment of cavernous sinus dural arteriovenous fistulae with radiosurgery and embolization.

OBJECTIVE: With the advent of interventional neuroradiology and stereotactic radiosurgery, dural arteriovenous fistulae are less often managed with open surgery. We evaluated the outcome of dural arteriovenous fistulae of the cavernous sinus treated with a combination of radiosurgery and embolization. MATERIAL AND METHODS: Twenty dural arteriovenous fistulae located in the cavernous sinus were enrolled in our study. Fifteen patients received X-knife radiosurgery alone and 5 also required embolization, one before radiosurgery and 4 after radiosurgery. The mean volume of the lesions was 2.8 ml (range 0.2-12.6), the corresponding radiation volume was 6.5 ml (range 0.6-24.6), and the conformity index was 2.9 (range 1.8-5.3). The mean peripheral and maximum radiation dose was 17.8 Gy (range 17-20) and 28.3 Gy (range 19-37) Gy, respectively. The clinical and imaging data were analyzed. RESULTS: The mean follow up period was 29 months (23-39). Seventy-five percent (15/20) of patients receiving radiosurgery alone achieved a symptomatic cure and with additional embolization 90% (18/20) were cured. All patients achieved cure on imaging after radiosurgery alone or in combination with embolization. Abnormal imaging findings were observed in two patients after treatment, one had an intracerebral hemorrhage and the other radiation edema, but both were asymptomatic. CONCLUSION: With multidisciplinary treatment with combined radiosurgery and embolization, satisfactory results can be achieved for dural arteriovenous fistulae with a low complication rate. In patients with mild symptoms, radiosurgery is the initial treatment option. Embolization should be performed in patients with severe symptoms or who have failed radiosurgery.     

The treatment of skull base meningiomas – combining surgery and radiosurgery

While the operative results for treating skull base meningiomas have improved due to modern microsurgical techniques, surgery is still accompanied by a high morbidity rate. Over the last 6 years, we operated on 50 patients with intracranial meningiomas, 23 of which were skull-based lesions. Among these patients with skull base meningiomas, seven (30%) were treated with both surgery and radiosurgery.All patients received standard operative procedures. Five patients received subtotal resections and two patients received partial resections. No mortalities occurred in our series. Following the operations, the clinical status improved in six patients, while only one patient (with a tuberculum sellae meningioma) experienced deterioration of a preexisting visual disturbance. Radiosurgery was performed at a mean of 4.3 months after the operations. One patient was treated by a two-staged radiosurgery regimen in light of the patient's large tumour volume (57.5 cm(3)). The treatment volume of the series ranged from 0.3 to 29.6 cm(3)(mean 11.6 cm(3)), and the minimum dose for the tumours was from 8 Gy to 12 Gy (mean, 11.6 Gy). Tumour regression was observed in three patients (43%) during the follow up period for radiosurgery (mean: 28 months). No patients revealed tumour growth in the follow up period or suffered symptomatic radiation injury. The clinical status remained unchanged in each of the seven patients after radiosurgery. Although we treated only seven patients with skull base meningiomas using surgery combined with radiosurgery, and the follow up period has been short, we believe that such combination treatment may be a very useful option in selected patients.