46. Radiology Case 9

James Flannery¹ and Joshua K. Aalberg¹

(1)

Department of Emergency Medicine, Wexner Medical Center at The Ohio State University, Columbus, OH, USA

James Flannery

Email: James.flannery@osumc.edu

Joshua K. Aalberg (Corresponding author)

Email: joshua.aalberg@osumc.edu

Keywords

Sagittal venous sinus thrombosisHyperdense cortical veinStroke symptomsPapilledemaEncephalopathyResonance Imaging (MRI)

Indication for the Exam

33 y/o f with a past medical history of blood clots presents with 2 days of headache and generalized weakness.

Diagnosis

Sagittal venous sinus thrombosis

../images/463721_1_En_46_Chapter/463721_1_En_46_Figa_HTML.jpg — Hyperdense dural sinus indicating an acute thrombus in the superior sagittal sinus on a non-contrast head computed tomography (CT)

../images/463721_1_En_46_Chapter/463721_1_En_46_Figb_HTML.jpg — Thrombus surrounded by enhancing dura creates an “empty delta sign” on the venous phase contrast head CT (CTV)

../images/463721_1_En_46_Chapter/463721_1_En_46_Figc_HTML.jpg — A hyperdense cortical vein causes a “cord sign,” indicating an acute thrombosis involving a cortical vein on this non-contrast head CT

../images/463721_1_En_46_Chapter/463721_1_En_46_Figd_HTML.jpg — “Blooming artifact” indicates acute dural and cortical venous thrombosis on this Magnetic Resonance Imaging (MRI) Susceptibility weighted imaging (SWI) sequence

Learning Points

Priming Questions

What will a dural venous thrombosis look like on non-contrasted versus contrasted head CTs?
How do you distinguish true thrombus versus variant anatomy?
What patients are at high risk for dural venous thrombosis?

Introduction/Background

Dural venous thrombosis (or cerebral venous thrombosis, CVT) is an occlusion of the intracranial dural sinuses, which function to drain intracranial venous blood and cerebrospinal fluid. The network of dural venous sinuses is extensive and eventually drains into the internal jugular veins. A CVT can cause a wide range of neurologic symptoms but the most common presentation is headache. Other potential symptoms include seizure, focal neurological deficits which may mimic typical stroke symptoms, papilledema, and encephalopathy.⁸ Dural venous thrombosis accounts for 0.5–1% of all strokes [1].

Pathophysiology/Mechanism

Dural venous thrombus leads to occlusion of the venous drainage and eventually local edema and intracranial hypertension which can progress to ischemia and/or hemorrhage. The clinical course is highly variable, ranging from hours to upwards of 1 month [2]. A risk factor for venous thrombosis is identified in a majority of cases and should raise clinical suspicion if present. There are numerous risk factors, but some of the most commonly encountered include: