Snapshot A previously healthy 29-year-old female presents with a progressive, diffuse headache and vomiting. She has no active illnesses, takes a multivitamin, and an oral contraceptive. On exam, there is edema on the scalp, papilledema on fundoscopy, and bilateral muscle weakness. Noncontrast head CT shows a hyperdense lesion in a part of the superior sagittal sinus. Overview Introduction Structure reflections in dura matter where meningeal and periosteal layers split Function return blood from cerebral veins to internal jugular vein Main examples superior sagittal sinus superior to falx cerebri tributary of the confluence of sinuses inferior sagittal sinus inferior to falx cerebri tributary to the straight sinus cavernous sinus lateral to the sella turcica tributary of the transverse sinus and sigmoid sinus contains CN III, IV, V1, V2, VI, and internal carotid clinical correlate cavernous sinus thrombosis spread of infection from superficial and deep face to cavernous sinus present with symptoms relating to compression of cranial nerves CN VI usually affected first patient cannot abduct eye Clinical importance venous sinus thrombosis → increases intracranial pressure obstruction → increases venous pressure consequences include: decreases capillary perfusion pressure impairs blood brain barrier → vasogenic edema impairs CSF reabsorption brain parenchymal damage venous hemorrhage causes include: prothrombotic diseases e.g., factor V leiden mutation, protein C or S deficiency, antithrombin deficiency oral contraceptives (OCP) pregnancy malignancy