Meningioma of the foramen magnum: A series of 40 cases

Long-Term Experience of Gamma Knife Radiosurgery for Benign Skull Base Meningiomas

“…1-12 38 The variation of total recurrence rates among the surgical series (from 0% to 17%, median 6.7%) is seemingly caused by the range of the follow up periods. [1][2][3][4][5][6][7][8][9][10][11][12] Furthermore, the recurrence/progression rates increase with the duration of follow up, and also seem to be influenced by tumour site and specific histopathological factors. 3 34 studies, proved that the long term recurrence rates of microsurgically treated meningiomas are often underestimated.…”

“…1 However, microsurgical resection of these tumours is frequently associated with considerable aggravation or new onset of neurological impairment, [1][2][3][4][5][6][7][8][9][10][11][12] and meningioma recurrences are observed even when complete removal has been accomplished. 1 3-6 9 12 13 Therefore, surgery alone cannot be the ideal solution to treat all skull base meningiomas, and less invasive therapeutic options have to be considered not only as adjunctive but as alternative primary treatment.…”

Surgical Experience With Skull Base Approaches for Foramen Magnum Meningioma.

“…2,4,5,10,11,15,16,24,26,27) Meningiomas in the foramen magnum area frequently elude early diagnosis because their ill-defined symptoms mimic cervical spondylosis, multiple sclerosis, syringomyelia, normal pressure hydrocephalus, amyotrophic lateral sclerosis, Chiari type I malformation, cervical disc disease, carpal tunnel syndrome, other intramedullary or extramedullary tumors, and even carotid artery stenosis. 17,20,23,32) Foramen magnum meningioma has been identified in our department since 1983, due to the introduction of CT in 1976 and MR imaging in 1983.…”

“…11) This benign intradural extramedullary tumor occurs infrequently, as about 1% of primary brain tumors according to the Brain Tumor Registry of Japan. 6) Foramen magnum meningioma is often identified only at an advanced stage due to the unusual and unrecognized pathognomonic symptomatology.…”

“…3,9) Total removal of foramen magnum meningioma is difficult and is associated with high rates of complications and recurrence even if performed by experienced surgeons, 18) and may result in high morbidity and mortality or incomplete removal. 4,7,11,22) The surgical management of patients with foramen magnum meningioma has changed over the past decades, because of various factors including improved diagnostic imaging, and advances in microsurgery and skull base techniques. Despite the very large number of reported meningiomas, the evolution of the surgical treatment of foramen magnum meningioma throughout the last three decades is unclear.…”