Rajput Muhammad Shaheryar Ahmed, Ahmad Ahmad Nawaz, Arain Asif Ali, Adeel Mohammad, Akram Saeed, Awan Muhammad Sohail, Bari Muhammad Ehsan
Otolaryngology, Liaquat University of Medical and Health Sciences, Karachi, PAK.
Otolaryngology, Liaquat National Hospital and Medical College, Karachi, PAK.
Cureus. 2018 Dec 4;10(12):e3684. doi: 10.7759/cureus.3684.
Introduction Vestibular schwannomas (VS) are the most common benign neoplasms of a cerebellopontine angle (CPA), which arise from the Schwann cells of the vestibulocochlear nerve. Eighty percent of CPA tumors are VS followed by meningioma as the second common mass lesion in this critical potential space. Treatment options range from watchful waiting with serial imaging studies to radiosurgery or a microsurgical excision or a combination of surgery and radiation therapy. The primary objective of the study was to assess hearing and facial nerve status before and after the surgery via the retrosigmoid approach. Methods The database of Aga Khan University Hospital was searched for diagnoses of vestibular schwannomas between 2000 and 2007. A total of 35 patients were identified; among them, 27 were selected for the study who met the inclusion criteria. The variables of the study were age, gender, presenting symptoms, size of the tumor, surgical approach, hearing levels, and facial nerve function. Hearing loss was categorized according to the Gardener-Robertson hearing classification and the House-Brackmann Scale was used for facial nerve assessment. Results Out of the 27 patients, 18 were male and nine were female. The mean age was 43 years. The most common presenting complaint was hearing loss and tinnitus, seen in 21 patients. Headache was present in six patients, ataxia in five, and vertigo in three. Facial nerve weakness was noticed in six patients. Two patients had Grade-III paralysis, three had Grade-IV paralysis, and one had Grade-V paralysis. The audiogram confirmed the presence of sensorineural hearing loss (SNHL) in all patients. Twelve patients out of 27 had Class II hearing with the threshold between 31 and 50 decibels and a Speech Discrimination Score (SDS) of 50% to 69%. Ten patients had non-serviceable hearing and the remaining five had poor hearing. The audiogram was repeated after surgery for those 12 patients who had Class II hearing and showed that seven out of 12 patients maintained a hearing threshold within the range of Class II at the one-year follow-up (hearing preservation 58%). The facial nerve preservation rate was 56% considering House-Brackmann Grade III or less as acceptable facial nerve function. Conclusion The optimal treatment for small vestibular schwannomas is a matter of controversy; however, the choice of treatment for large vestibular schwannomas in patients without significant comorbidity is generally microsurgical excision. The surgical excision of a large VS with the retrosigmoid approach is found to be safe consistently. The hearing and facial nerve preservation in our study were found comparable with the literature.
引言
前庭神经鞘瘤（VS）是桥小脑角（CPA）最常见的良性肿瘤，起源于前庭蜗神经的施万细胞。CPA区80%的肿瘤是VS，其次是脑膜瘤，是这个关键潜在间隙中第二常见的占位性病变。治疗方案包括通过系列影像学检查进行观察等待、放射外科治疗、显微手术切除或手术与放射治疗相结合。本研究的主要目的是通过乙状窦后入路评估手术前后的听力和面神经状况。
方法
检索阿迦汗大学医院数据库中2000年至2007年间前庭神经鞘瘤的诊断记录。共识别出35例患者；其中，27例符合纳入标准的患者被选入研究。研究变量包括年龄、性别、临床表现、肿瘤大小、手术入路、听力水平和面神经功能。听力损失根据Gardener-Robertson听力分级进行分类，面神经评估采用House-Brackmann量表。
结果
27例患者中，18例为男性，9例为女性。平均年龄为43岁。最常见的临床表现是听力损失和耳鸣，21例患者出现此症状。6例患者有头痛，5例有共济失调，3例有眩晕。6例患者出现面神经麻痹。2例患者为III级麻痹，3例为IV级麻痹，1例为V级麻痹。听力图证实所有患者均存在感音神经性听力损失（SNHL）。27例患者中有12例听力为II级，阈值在31至50分贝之间，言语辨别得分（SDS）为50%至69%。10例患者听力无法使用，其余5例听力较差。对12例听力为II级的患者术后复查听力图，结果显示12例患者中有7例在一年随访时听力阈值维持在II级范围内（听力保留率为58%）。将House-Brackmann III级或更低级别视为可接受的面神经功能时，面神经保留率为56%。
结论
小型前庭神经鞘瘤的最佳治疗方法存在争议；然而，对于无明显合并症的大型前庭神经鞘瘤患者，治疗选择通常是显微手术切除。采用乙状窦后入路对大型VS进行手术切除一直被认为是安全的。我们研究中的听力和面神经保留情况与文献报道相当。
