Abstract：
BACKGROUND: To investigate the classification and microsurgical treatment of foramen magnum meningioma (FMM).
METHODS: We retrospectively analyzed 76 patients with FMM and classified them into two classifications, classification ABS according to the relationship between the FMM and the brainstem and classification SIM according to the relationship between the FMM and the vertebral artery (VA). All patients underwent either the far lateral approach (54 cases) or the suboccipital midline approach (22 cases).
RESULTS: Of the 76 cases, 47 cases were located ahead of the brainstem (A), 16 cases at the back of the brainstem (B), and 13 cases were located laterally to the brainstem (S). There were 15 cases located superior to the VA (S), 49 cases were inferior (I), and 12 cases were mixed type (M). Among 76 cases, 71 cases were resected with Simpson grade 2 (93.42%), 3 with Simpson grade 3 (3.95%), and 2 with Simpson grade 4 (2.63%). We summarized four anatomical triangles: triangles SOT, VOT, JVV, and TVV. The mean postoperative Karnofsky performance score was improved in all patients (p < 0.05). However, several complications occurred, including hoarseness and CSF leak.
CONCLUSIONS: ABS and SIM classifications are objective indices for choosing the surgical approach and predicting the difficulty of FMMs, and it is of great importance to master the content, position relationship with the tumor, and variable anatomical structures in the four \"triangles\" for the success of the operation.
METHODS: We retrospectively analyzed 76 patients with FMM and classified them into two classifications, classification ABS according to the relationship between the FMM and the brainstem and classification SIM according to the relationship between the FMM and the vertebral artery (VA). All patients underwent either the far lateral approach (54 cases) or the suboccipital midline approach (22 cases).
RESULTS: Of the 76 cases, 47 cases were located ahead of the brainstem (A), 16 cases at the back of the brainstem (B), and 13 cases were located laterally to the brainstem (S). There were 15 cases located superior to the VA (S), 49 cases were inferior (I), and 12 cases were mixed type (M). Among 76 cases, 71 cases were resected with Simpson grade 2 (93.42%), 3 with Simpson grade 3 (3.95%), and 2 with Simpson grade 4 (2.63%). We summarized four anatomical triangles: triangles SOT, VOT, JVV, and TVV. The mean postoperative Karnofsky performance score was improved in all patients (p < 0.05). However, several complications occurred, including hoarseness and CSF leak.
CONCLUSIONS: ABS and SIM classifications are objective indices for choosing the surgical approach and predicting the difficulty of FMMs, and it is of great importance to master the content, position relationship with the tumor, and variable anatomical structures in the four \"triangles\" for the success of the operation.
摘要：
背景：探讨大孔脑膜瘤（FMM）的分类和显微外科治疗。
方法：我们回顾性分析了76例FMM患者，并将其分为两个分类，根据FMM与脑干的关系对ABS进行分类,根据FMM与椎动脉(VA)的关系对SIM进行分类。所有患者均采用远外侧入路（54例）或枕下中线入路（22例）。
结果：76例中，47例位于脑干前方（A），16例脑干后部（B），13例位于脑干（S）的侧面。有15例位于VA（S）上方，49例次(I)，12例为混合型(M)。在76例病例中，手术切除71例，Simpson2级（93.42%），3，辛普森3级（3.95％），和2，辛普森四级（2.63%）。我们总结了四个解剖三角形：三角形SOT，VOT,JVV,和TVV。所有患者的平均术后Karnofsky表现评分均得到改善(p<0.05)。然而,发生了一些并发症，包括声音嘶哑和脑脊液漏.
结论：ABS和SIM分类是选择手术方式和预测FMM难度的客观指标，掌握内容非常重要，与肿瘤的位置关系，以及四个“三角形”中的可变解剖结构，以确保手术成功。
方法：我们回顾性分析了76例FMM患者，并将其分为两个分类，根据FMM与脑干的关系对ABS进行分类,根据FMM与椎动脉(VA)的关系对SIM进行分类。所有患者均采用远外侧入路（54例）或枕下中线入路（22例）。
结果：76例中，47例位于脑干前方（A），16例脑干后部（B），13例位于脑干（S）的侧面。有15例位于VA（S）上方，49例次(I)，12例为混合型(M)。在76例病例中，手术切除71例，Simpson2级（93.42%），3，辛普森3级（3.95％），和2，辛普森四级（2.63%）。我们总结了四个解剖三角形：三角形SOT，VOT,JVV,和TVV。所有患者的平均术后Karnofsky表现评分均得到改善(p<0.05)。然而,发生了一些并发症，包括声音嘶哑和脑脊液漏.
结论：ABS和SIM分类是选择手术方式和预测FMM难度的客观指标，掌握内容非常重要，与肿瘤的位置关系，以及四个“三角形”中的可变解剖结构，以确保手术成功。
