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

Abstract

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. The purpose of this paper is to present our experience in the surgery of FMM. Since 1938, numerous series have been published but they are very heterogeneous with high variability of location and surgical approaches. 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. 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. In this paper, we present five cases of operated FMM, describe our approaches, the reason of each approach and propose some surgical remarks.