Introduction: Meningiomas of the foramen magnum occupy between 1.8-3.2% of all intracranial meningiomas. The surgical approach of choice for these tumors remains controversial. The aim of this study is to present our surgical experience with the medial suboccipital approach with reduced lateral suboccipital minicraniectomy with resection of the posterior arch of C1, and C2 hemilaminectomy according to the distal extent of the tumor as a possible management of foramen magnum meningiomas.

Methods: We reviewed a series of 6 cases of patients with meningiomas of the foramen magnum taken to resection with a reduced lateral suboccipital approach between 2015 and 2016 at the National Cancer Institute, Bogotá D.C., Colombia. Demographic, clinical, radiological and surgical variables are described.

Results: Four of them were female; the mean age was 63y (56-67y). The main symptom was occipito-cervical pain. The antero-lateral location to foramen magnum was the most frequent (4 cases). Partial resection of the posterior hemiarcoid of C1 was performed in 5 patients. A resection of the posterior arch of C1 and an hemilaminectomy of C2 with complete resection of the tumor was performed in the other patient. The histopathological diagnoses were 5 meningothelial meningiomas and 1 transitional meningioma. There was resolution of the symptomatology, with complete resections of the lesions, without requirement of complementary management, nor tumor recurrence at 1 year of follow-up.

Conclusions: Reduced lateral suboccipital resection can adequately be used for successful resection foramen magnum meningiomas.

Patient Care: Decrease neurovascular injury in foramen magnum meningiomas resection.

Learning Objectives: Describe a reduced lateral suboccipital apporach for resection of foramen mangum meningioma. Describe the anatomy and the surgical nuances of this approach.

References: 1. Bruneau M, George B. Foramen magnum meningiomas: detailed surgical approaches and technical aspects at Lariboisière Hospital and review of the literature. Neurosurg Rev [Internet]. 2008 Jan [cited 2015 Nov 5];31(1):19–32; discussion 32–3. Available from: http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=2077911&tool=pmcentre z&rendertype=abstract 2. George B, Lot G, Boissonnet H. Meningioma of the foramen magnum: a series of 40 cases. Surg Neurol [Internet]. 1997 Apr [cited 2015 Nov 5];47(4):371– 9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/9122842