Figure 7f. Thrombosis of the superior sagittal sinus and venous infarction in a 25-year-old woman who was 34 weeks pregnant and developed headaches and blurring of vision. (a) Axial CT scan shows high attenuation in the superior sagittal sinus (curved arrows) and focal hemorrhage in the left parietal lobe at the gray-white matter interface (straight arrow). (b–d) Sagittal T1-weighted (b), axial T2-weighted (c), and axial FLAIR (d) MR images show high signal intensity in the superior sagittal sinus (arrow). (e) Axial gadolinium-enhanced T1-weighted MR image shows a filling defect (empty delta sign) (arrow) in the superior sagittal sinus. (f) On a three-dimensional time-of-flight MR venogram, the superior sagittal sinus is not visualized because of extensive thrombosis.