Surgical Experience With Skull Base Approaches for Foramen Magnum Meningioma.

Abstract

The surgical treatment of patients with foramen magnum meningioma remains challenging. This study evaluated the outcome of this tumor according to the evolution of surgical approaches during the last 29 years. A retrospective analysis of medical records, operative notes, and neuroimages of 492 meningioma cases from 1972 to 2001 identified seven cases of foramen magnum meningioma (1.4%). All patients showed various neurological symptoms corresponding with foramen magnum syndrome. The tumor locations were anterior in five cases and posterior in two. Surgical removal was performed through a transoral approach in one patient, the suboccipital approach in three, and the transcondylar approach in two. Total removal was achieved in all patients, except for one who refused any surgical treatment. The major complications were tetraparesis and lower cranial nerve paresis for tumors in anterior locations, and minor complications for posterior locations. One patient died of atelectasis and pneumonia after a long hospitalization. The transcondylar approach is recommended for anterior locations, and the standard suboccipital approach for posterior locations.

Foramen magnum meningiomas: surgical treatment in a single public institution in a developing country

“…Complete, subtotal, and partial resections were reported in 77, 16, and 7%, respectively, in a multicentric study 27 , and most recent series reported predominantly complete or subtotal removal of the tumor and, exceptionally, partial removal 2,7,8,9,10,11,12,13,15,16,17,20,21,22,23,24,25,27,28,29,30 . Factors preventing complete resection are tumor adherences to CN/VA and invasiveness of the tumor 3,9,27 .…”

“…In the last two decades transient and permanent morbidity ranged from 0-72.5% 5,9,11,13,14,15,16,17,21,22,24,29 and from 0-30% 2,5,11,12,13,15,16,17,21,22,23,25,26,29,30 , respectively. Permanent morbidity is directed related to the location and extent of the tumor.…”

Foramen Magnum Meningioma: A Rare Case Report

“…The mortality rate is comprised between 0 and 25%. Mortality rates higher than 10% were mainly observed in small series 19 .…”

Foramen Magnum Meningioma: Dysphagia of Atypical Etiology

“…Meningiomas most often occur at the convexities and basal regions of the cerebrum; only 1.4-3.2% of meningiomas arise at the foramen magnum. 31,32 Because of an unusual constellation of symptoms and neurologic signs, foramen magnum tumors are often identified only after they have attained a large size. 6,[32][33][34] In a study of 40 cases of foramen magnum meningiomas, the most common early symptoms were posterior headache followed by paresthesias and motor deficits.…”

“…33 The anatomic proximity of a foramen magnum mass to the cerebellar tonsils, caudal medulla, lower cranial nerves, rostral spinal cord, and upper cervical nerves results in highly variable symptomatology that is commonly misdiagnosed. 6,32 The varied clinical presentation may lead to the initial diagnoses of multiple sclerosis, carpal tunnel syndrome, syringomyelia, and cervical spondylosis, which may delay appropriate therapy. 33 Whereas the most common symptoms are somatic sensory and motor dysfunction, bulbar dysfunction, including dysphagia and dysarthria caused by lower cranial nerve impairment, is known to be associated with foramen magnum meningiomas [31][32][33] .…”