Surgical management of a transosseous meningioma with invasion of torcula, superior sagittal sinus, transverse sinus, calvaria, and scalp.

Meningiomas involving both intradural and extradural structures are rare tumors. We report the complete resection of a massive complex transosseous meningioma that had invaded the torcula, superior sagittal sinus, occipital bone, and scalp.A 48-year-old male presented after 3 days of worsening headaches and blurry vision. Preoperative imaging demonstrated an 11 × 5-cm extra-axial mass that avidly enhanced with gadolinium in the region of the torcula. Angiography demonstrated occlusion of the involved portions of the superior sagittal sinus, torcula, and proximal left transverse sinus. Cortical drainage occurred via the veins of Labbι and deep drainage via an occipital sinus. Using image-guided stereotaxy, a wide-excision scalp resection and craniectomy with sinus exploration was planned for complete tumor removal. Parasitized cortical veins were preserved. Occluded portions of the superior sagittal sinus and left transverse sinus were resected along with the invaded parts of the falx and tentorium. The walls of the straight sinus, torcula, and right transverse sinus were repaired primarily to facilitate deep drainage. A latissimus dorsi free flap was used to reconstruct the scalp defect. Routine follow-up magnetic resonance imaging (MRI) at 18 months demonstrated no evidence of recurrence or regrowth.This case illustrates the importance of identifying aberrant venous drainage pathways when considering ligation and resection of major sinuses and discusses the management of calvarial and scalp invasion.