Management of meningiomas en plaque of the sphenoid wing.

OBJECT: The authors present their findings on growth patterns in a large series of surgically treated meningiomas en plaque of the sphenoid wing.

METHODS: A retrospective case analysis was performed in 67 patients (53 of whom were female) harboring meningiomas en plaque originating from the sphenoid wing, who underwent surgery between 1991 and 2002. The standard surgical approach consisted of pterional craniotomy and extradural resection of any infiltrated bone. The intracranial tumor was removed, and the dura mater and bone were reconstructed. The follow-up period ranged from 6 to 118 months (mean 45.7 months). Total macroscopic resection was achieved in 40 patients. Forty-eight meningiomas extended to the orbital roof and/ or the lateral orbital wall, 34 involved the extraconal space, and eight the intraconal space. Fifty-four tumors involved the superior orbital fissure, 46 the optic canal, and 21 the inferior orbital fissure. Twelve tumors infiltrated the cavernous sinus and 27 involved the anterior clinoid process. There were no deaths in this group of patients; the rate of minor morbidity was 11.9% and the rate of major morbidity was 3%. Subtotal resections were performed in 27 patients because there was intraorbital tumor (eight patients), tumor in the cavernous sinus (nine patients), tumor beyond the tentorial notch (three patients), tumor invading the superior orbital fissure (four patients), and tumor of the skull base (three patients). Five patients underwent postoperative three-dimensional conformal radiotherapy, which resulted in stable tumor volume at follow up. Tumor recurrence was identified in seven patients (10.4%) postoperatively (range of follow up 13-47 months).

CONCLUSIONS: The goal of surgery is complete tumor removal without morbidity. An exact analysis of tumor growth and its involvement of different structures is mandatory before performing surgery.