Surgery of the superior sagittal sinus in parasagittal meningiomas.

The management of 21 parasagittal meningiomas is described; three were located in the anterior third of the sinus, 14 in the middle third, and four in the posterior third. Of these, four meningiomas were attached only to the lateral wall, two invaded the external layer of only one sinus wall, two involved the lateral recess of the sinus, and seven invaded one or two sinus walls. The remaining six tumors invaded the three walls of the sinus, which was completely blocked. There was bilateral meningiomas in four cases. Complete excision of the meningioma with preservation of the venous flow in the sinus and its collateral veins was attempted in each case. In the first eight cases it was possible to preserve the patency of the sinus without graft. In six of the next seven cases the removal of the two invaded walls permitted preservation of the third healthy wall and entailed the repair of the two involved walls by a partial graft, either dural graft (three cases) or venous graft (three cases). In one of the last six cases, a total vein graft was performed after complete excision of the invaded sinus. Two cortical veins were sutured to a collateral branch of the autogenous vein graft. The surgical technique of the partial and the total vein graft is described and clinical results and angiographic controls are discussed.