Foramen Magnum Meningioma: Some Anatomical and Surgical Remarks through Five Cases.

STUDY DESIGN: Foramen magnum meningioma foramen magnum meningioma (FMM) represents 2% all of meningiomas. The clinical symptomatology is usually insidious and consists of headache, neck pain and hypoesthesia in C2 dermatome. Because of their location, the management is challenging.

PURPOSE: The purpose of this paper is to present our experience in the surgery of FMM.

OVERVIEW OF LITERATURE: Since 1938, numerous series have been published but they are very heterogeneous with high variability of location and surgical approaches.

METHODS: During two years, we operated 5 patients with FMM. All the patients had magnetic resonance imaging (MRI) with angio-MRI to study the relationship between tumour and vertebral artery (VA). In all the cases, we used prone position.

RESULTS: In one case, considering the tumour localization (posterior and pure intradural) the tumour was removed via a midline suboccipital approach with craniotomy and C1-C2 laminectomy. In all other cases, meningiomas were posterolateral (classification of George) with extradural extension in one case. In all cases, VA was surrounded by tumor. So, we opted for a modified postero-lateral approach with inverted L incision, craniotomy and C1-C2 laminectomy without resect occipital condyle. Epidural part of VA was identified and mobilized laterally. Once VA was identified we opened dura mater and began to remove the tumour.

CONCLUSIONS: In this paper, we present five cases of operated FMM, describe our approaches, the reason of each approach and propose some surgical remarks.