Falx meningiomas: surgical results and lessons learned from 68 cases

Abstract

Objective: The purpose of this study was to review the characteristics of falcine meningioma retrospectively and to identify the parameters associated with tumor recurrence.

Methods: The analysis included; age, sex, extent of resection, and radiologic and pathologic findings. Falcine meningiomas were classified by location as anterior, middle, or posterior as described for parasagittal meningiomas.

Results: Of the 795 meningioma patients treated between 1990 and 2004 at the authors' institution, 68 patients with meningiomas arising from the falx underwent craniotomies. There were 22 male and 46 female patients (1 : 2.1). Mean age was 55 years and ranged from 14 to 77 years. Locations of falcine meningioma were; the anterior third in 33 cases, middle in 20, and posterior in 15. Mean tumor volume was 42 cc and ranged from 4 to 140 cc. In 58 of the 68 patients tumors were totally removed. Additional surgery for recurrence was performed in 6 patients over 15 years. Of these 6 patients, only two patients underwent gross total tumor resection at first operation; the other four underwent subtotal tumor resection. Based on pathologic reports, the largest tumor subtype was transitional. There were four patients with a high grade tumor-three atypical and one anaplastic meningioma. Of the 68 patients, 59 achieved a good outcome (no neurological deficit or recurrence), six had temporary complications, two suffered new permanent postoperative deficits, and the remaining one died due to severe brain swelling despite postoperative intensive care. Extent of surgical resection was found to be significantly related to tumor recurrence.

Conclusion: Falcine meningioma accounted for 8.5% of intracranial meningiomas and the transitional meningioma was the most common subtype of falcine meningioma. Gross total resection of tumor was the single most important predictor of an improved surgical outcome.

Keywords: Falcine meningioma; Histological subtype; Surgical results.

Fig. 1

Magnetic resonance image showing a lobulating mass attached to the falx. Mass with severe peritumoral edema compressing anterior cerebral arteries (ACA) on T2 weighted axial view (A). T1 enhanced sagittal view showing encasement of the ACA by the tumor (B).

Fig. 2

Cerebral angiography showing downward displacement of internal cerebral veins (A). The superior sagittal sinus is almost totally occluded by the tumor (B).

Fig. 3

Magnetic resonance venographs showing compression of a superior sagittal sinus by mass adjacent to the anterior (A) and posterior falx (B), respectively.