[Craniovertebral intradural meningiomas: analysis of postoperative outcomes (a retrospective two-center study)].

Objective: To analyze the postoperative outcomes in patients with craniovertebral meningiomas with preoperative justification of surgical approach depending on tumor localization.

Material and methods: We examined 36 patients with craniovertebral meningiomas. The Karnofsky, Frankel and cranial nerve dysfunction scales were used to assess functional status of patients. Preoperative contrast-enhanced MRI was valuable to verify tumor matrix. MRI and assessment of neurological status were performed 2 weeks and 1 year after surgery.

Results: Mean preoperative Karnofsky score was 65.52±6.41, in postoperative period - 71.71±14.16, after 1 year - 86.9±5.61. Baseline dysfunction of caudal cranial nerves was noted in 22.2% of patients. After 2 postoperative weeks, this value increased to 55.6% (20 patients). After one postoperative year, mild dysfunction of caudal cranial nerves persisted in 9 patients (25%). Patients were divided into 3 groups depending on localization of tumor matrix in sagittal plane: lower third of the clivus - 15 (41.7%) patients, level of foramen magnum - 18 (50%) patients, level of C1-C2 vertebrae - 3 (8.3%) patients. Two groups were distinguished depending on localization of tumor matrix in axial plane: anterior (anterolateral) - 27 patients (75%), posterior (posterolateral) - 9 patients (25%). We analyzed the relationship between tumor volume, localization of matrix and incidence of postoperative complications.

Conclusion: Localization of tumor matrix at the level of the lower third of the clivus is accompanied by larger tumor volume and higher complication rate compared to localization of neoplasm at the level of foramen magnum and C1-C2 vertebrae. Posterolateral approach is optimal for anterior and anterolateral tumors, while median suboccipital approach is advisable for posterior and posterolateral tumors.