Cerebral Venous Sinus Thrombosis (CVST)

Figure 1: Axial image of the brain shows ill-defined areas of hypoattenuation (stars) in bilateral frontal lobes involving both gray and white matter, in a nonarterial distribution.

Figure 2: A lateral view of CT venography shows occluded anterior 1/3 of the superior sagittal sinus (arrows).

Facts

• 0.5% of all strokes
• Peak incidence in neonates and adults in third decade of life (female:male = 5:1.5)
• Clinical presentation varies widely from relatively mild symptoms to devastating hemorrhage
• Risk factors following Virchow's triad: blood stasis, changes in vessel wall, and changes in blood composition
• Intravenous heparin and subcutaneous low-molecular-weight heparin are primary Rx for acute CVST. Hemorrhage does not preclude the diagnosis.
• Patient prognosis depends on location of CVST (best if in cortical vein, anterior superior sagittal sinus, isolated transverse and isolated sigmoid sinus) and extent of involvement (the more segments of veins involved, the greater complications)

Imaging

• Infarction or hemorrhagic infarction in non-arterial distribution
• Delta sign = filling defect (clot) surrounded by enhanced venous blood in the affected sinus and dural enhancement
• MRI shows T1 hyperintensity and lack of flow void
• Look for potential etiology (and vice versa): paranasal sinus and mastoid infection

References

1. Qureshi AI. Textbook of interventional neurology. 2011

2. Castillo M. Neuroradiology companion: methods, guidelines and imaging fundamentals. 2006

3. Zubkov AY, McBane RD, Brown D, Rabinstein AA. Brain lesions in cerebral venous sinus thrombosis. Stroke 2009;40:1509