Introduction: Purely ventral foramen magnum meningiomas are challenging tumors to treat given their location, proximity and relationship to the brainstem, lower cranial nerves and vertebral arteries. Endoscopic endonasal surgery (EES) has recently been introduced as an alternative to traditional approaches in the management of these tumors.
Methods: From May 2008 to October 2013, 5 patients underwent EES for primary ventral foramen magnum meningiomas. We retrospectively reviewed their records to evaluate outcomes.
Results: Three patients presented with long-tract and lower cranial nerves deficits. Gross or near total resection was achieved in every case. Preoperative median Karnofsky score was 80 (range: 40-100) which improved to 100 postoperatively (range: 90-100). Preexisting long-tract and lower cranial nerves deficits improved in every patient and normalized in 2 (66.7 %). Following EES, one patient (20%) developed CSF leak that resulted in meningitis. Other complications included epidural abscess formation in one patient following necrosis of the nasoseptal flap which was surgically treated. Hydrocephalus occurred in 2 patients without long-term deficits after ventriculo-peritoneal shunt insertion. Two patients developed deep venous thrombosis, which resulted in a pulmonary embolism in one of them; they were managed with anticoagulation without further sequelae. No one developed occipito-cervical instability following EES. There were no new lower cranial neuropathies but one patient developed partial abducens nerve palsy. There was no operative mortality.
Conclusions: EES is a competitive alternative to open approaches for the treatment of purely ventral foramen magnum meningiomas with good results when performed by experienced endoscopic skull base surgeons.
Patient Care: The endoscopic endonasal approach to ventral foramen magnum meningiomas represents a safe and efficient technique with good surgical outcomes and low morbidity.
Learning Objectives: Describe endoscopic endonasal surgery as a good alternative to traditional approaches for ventral foramen magnum meningiomas.