Adaptative Diploic Vein Bypass of the Superior Sagittal Sinus in a Large Falcine Meningioma.

We describe an adaptative bypass at the posterior third of the superior sagittal sinus (SSS) through the parietal diploe veins related to a large falcine meningioma on a 55-year-old lady with progressive headaches and mild left hemiparesis. Cranial imaging revealed a large tumor at the posterior third of the cerebral falx, compatible with meningioma. Imaging also revealed lack of continuity of the superior sagittal sinus at that region. Large diploic veins were seen bypassing the segment of the SSS affected by the tumor. An "L"-shaped modified posterior interhemispheric craniotomy was performed to avoid traversing the diploic veins. Near-total resection of the meningioma was accomplished. Postoperative imaging revealed a small remnant invading the SSS, which was treated with adjuvant radiotherapy. The patient tolerated the procedure well and was discharged to rehabilitation unit on postoperative day 5 with no neurologic deficits.