Santoreneos S, Hanieh A, Jorgensen R E
Department of Surgery, Queen Elizabeth Hospital, Adelaide, Australia.
Neurosurgery. 1997 Jul;41(1):282-7. doi: 10.1097/00006123-199707000-00050.
Despite their predilection for sensory nerves, intracranial schwannomas have been reported in a number of mixed and purely motor cranial nerves, especially in association with Type 2 neurofibromatosis. We report the rare occurrence of a trochlear nerve schwannoma in a patient without neurofibromatosis and review 17 other case reports from the literature.
A 35-year-old woman presented with an 8-week history of evolving left hemiparesis, bilateral bulbar paresis, and out-of-character emotional lability.
She underwent a left temporal craniotomy and a subtemporal, transtentorial approach to the tentorial hiatus, with complete excision of a cisternal trochlear nerve schwannoma.
Postoperative complications included temporary oculomotor and abducens nerve palsies and temporary right hemiparesis and mild expressive dysphasia, which were resolved at 23-month follow-up. Preoperative symptoms and signs completely resolved, but a postoperative complete trochlear nerve palsy required inferior oblique myectomy for correction of diplopia. A review of the literature showed no preoperative trochlear nerve involvement in at least 45% of cases. The tumor is isointense on T1- and T2-weighted magnetic resonance images and enhances brightly with gadolinium. The most frequently used approach for surgical excision is the subtemporal approach, and the tumor is almost always totally excised. Long-term follow-up suggests recovery of preoperative deficit, and persisting or new trochlear nerve palsy is the rule.
尽管颅内神经鞘瘤好发于感觉神经，但也有报道称其可发生于多条混合性及纯运动性颅神经，尤其是与2型神经纤维瘤病相关时。我们报告1例无神经纤维瘤病患者发生滑车神经鞘瘤的罕见病例，并复习文献中的其他17例病例报告。
一名35岁女性，有8周逐渐进展的左侧偏瘫、双侧延髓麻痹及性格改变后的情绪不稳定病史。
她接受了左侧颞部开颅手术，并采用颞下经小脑幕入路至小脑幕裂孔，完整切除了脑池内的滑车神经鞘瘤。
术后并发症包括暂时性动眼神经和外展神经麻痹、暂时性右侧偏瘫及轻度表达性失语，在23个月的随访中均已缓解。术前症状和体征完全消失，但术后出现完全性滑车神经麻痹，需要行下斜肌切除术以矫正复视。文献复习显示，至少45%的病例术前滑车神经未受累。该肿瘤在T1加权和T2加权磁共振图像上呈等信号，钆增强后明显强化。手术切除最常用的入路是颞下入路，肿瘤几乎总是能完全切除。长期随访提示术前功能缺损可恢复，持续性或新发滑车神经麻痹较为常见。
