Department of Neurosurgery, Hospital 12 de Octubre, Madrid, Spain.
Neurosurgery. 2010 Apr;66(4):E841-2. doi: 10.1227/01.NEU.0000367550.30165.A7.
To describe the surgical and ultrastructural findings in the trigeminal root of a patient with trigeminal neuralgia (TN) associated with a cerebellopontine epidermoid tumor, and to relate these to literature reports of patients with vascular compression-related TN.
A 39-year-old woman presented with right TN. She had a 10-year history of lancinating pain paroxysms in the second and third trigeminal branches. Pain exhibited trigger areas and improved partially with carbamazepine. Cranial magnetic resonance imaging revealed an epidermoid tumor in the right cerebellopontine angle that distorted and compressed the right trigeminal root.
The tumor was resected. At operation, the trigeminal root appeared distorted and compressed by the tumor. A small partial rhizotomy was performed, and the biopsy was processed for ultrastructural study. Complete relief of the symptoms was achieved with no deficits after the procedure. Pathologic changes in the biopsy included axonal loss, demyelination, and the presence of abundant collagen infiltrates and myelin debris. No inflammatory cells were present. In some areas, myelin-denuded axons were in close apposition, allowing the presence of axon-to-axon interactions. These findings are similar to others described previously regarding patients with vascular compression-related TN.
Compression injury to the trigeminal root leading to demyelination is a major determinant in the pathogenesis of TN.
描述与桥小脑角表皮样瘤相关的三叉神经痛（TN）患者三叉神经根的手术和超微结构发现，并将这些发现与血管压迫相关 TN 患者的文献报告进行比较。
一位 39 岁女性出现右侧 TN。她有 10 年的右侧第二和第三三叉神经分支发作性刺痛疼痛史。疼痛有触发区，卡马西平部分缓解。颅磁共振成像显示右侧桥小脑角表皮样瘤，扭曲并压迫右侧三叉神经根。
切除肿瘤。术中发现三叉神经根被肿瘤扭曲和压迫。进行了小部分神经根切断术，并对活检进行了超微结构研究。手术后症状完全缓解，无任何缺陷。活检的病理改变包括轴索丢失、脱髓鞘以及大量胶原浸润和髓磷脂碎片。没有炎症细胞。在某些区域，髓磷脂脱失的轴索紧密相邻，允许轴突与轴突之间的相互作用。这些发现与以前关于血管压迫相关 TN 患者的描述相似。
导致脱髓鞘的三叉神经根受压是 TN 发病机制的主要决定因素。
