Almefty Kaith K, Mooney Michael A, Al-Mefty Ossama, Essayed Walid Ibn, Bi Wenya Linda, Cai Li, Kadri Paulo A S
Department of Neurosurgery, Barrow Neurological Institute, Phoenix, Arizona, USA.
Department of Neurosurgery, Brigham and Women`s Hospital, Harvard Medical School, Boston, Massachusetts, USA.
World Neurosurg. 2022 Dec;168:e187-e195. doi: 10.1016/j.wneu.2022.09.082. Epub 2022 Sep 20.
Facial nerve (FN) schwannomas are extremely rare. According to their origin and involved segment(s), they constitute distinct subtypes. Intact FN function presents a management challenge, particularly in the cerebellopontine angle cisternal subtype that masquerades as a vestibular schwannoma. Fascicular-sparing technique with subtotal resection can maintain a good FN function. This study focuses on management to maintain good FN function.
A retrospective analysis of a cohort of 13 patients harboring FN schwannoma. Patient demographics, clinical findings, imaging, surgical intervention, and outcomes were analyzed.
Five women and 8 men, with an average age of 55.3 years (39-75 years), harbored 6 cisternal, 2 ganglion, and 5 combined tumors. Average tumor size was 28.3 mm (16-50 mm). Eleven patients underwent surgery. Seven patients had fascicle-sparing technique, 5 of whom maintained their preoperative FN function, whereas 2 patients with near-total removal had a deterioration in FN function. Two patients with preoperative complete facial paralysis had gross total removal with interposition nerve graft.
FN schwannomas management is individualized according to the subtype and the FN function at presentation. When FN function is normal, observation can be applied for prolonged period of time. At the early sign of deterioration, sub- or near-total resection with fascicle sparing technique can be performed. The cisternal subtype masquerade as vestibular schwannoma and should be recognized at the initial exposure by the appearance of finely splayed nerve fascicles at the perimetry of the tumor which elicits a motor response at low threshold stimulation.
面神经（FN）神经鞘瘤极为罕见。根据其起源和累及节段，可分为不同亚型。保留完整的FN功能对治疗提出了挑战，尤其是在桥小脑角池亚型中，其表现类似前庭神经鞘瘤。采用保留束状结构的次全切除术可维持良好的FN功能。本研究聚焦于维持良好FN功能的治疗方法。
对13例FN神经鞘瘤患者进行回顾性分析。分析患者的人口统计学资料、临床表现、影像学检查、手术干预及治疗结果。
13例患者中，女性5例，男性8例，平均年龄55.3岁（39 - 75岁），其中6例为池段肿瘤，2例为神经节肿瘤，5例为混合型肿瘤。肿瘤平均大小为28.3 mm（16 - 50 mm）。11例患者接受了手术。7例患者采用了保留束状结构的手术方法，其中5例患者维持了术前的FN功能，而2例次全切除的患者FN功能恶化。2例术前完全性面瘫患者接受了肿瘤全切并进行了神经移植。
FN神经鞘瘤的治疗应根据亚型及就诊时的FN功能进行个体化处理。当FN功能正常时，可长时间观察。在功能出现早期恶化迹象时，可采用保留束状结构的次全或近全切除术。池段亚型表现类似前庭神经鞘瘤，在初次暴露时应通过肿瘤周边精细散开的神经束外观予以识别，这些神经束在低阈值刺激时会引发运动反应。
