What is CT venography?
What is CT venography?
CT cerebral venography (also known as a CTV head or CT venogram) is a contrast-enhanced examination with an acquisition delay providing an accurate detailed depiction of the cerebral venous system.
How is cerebral sinus thrombosis diagnosed?
How is cerebral venous sinus thrombosis diagnosed?
- MRI scan.
- CT scan.
- Venography.
- Angiography.
- Ultrasound.
- Blood tests.
Where is the sagittal sinus in the brain?
The superior sagittal sinus is one of several endothelial-lined spaces in the brain known collectively as the dural venous sinuses. It lies within the superior convex margin of the falx cerebri which attaches to the internal surface of the calvaria (in the midline).
How is CT venography performed?
Technique
- patient position. supine with their arms by their side.
- scout. CT to the vertex.
- scan extent. CT to the vertex.
- scan direction. caudocranial.
- contrast injection considerations. injection. 75-100 ml of non-ionic iodinated contrast.
- scan delay. 45 seconds (see practical points)
- respiration phase. suspended.
How long does a CT venogram take?
A venogram takes between 30 and 90 minutes to perform. Fluids will be run through your IV to remove the contrast material from your veins. You will also be instructed to drink a lot of fluids for the next day.
What does the sagittal sinus do?
The superior sagittal sinus (also known as the superior longitudinal sinus), within the human head, is an unpaired area along the attached margin of the falx cerebri. It allows blood to drain from the lateral aspects of anterior cerebral hemispheres to the confluence of sinuses.
What is the function of inferior sagittal sinus?
The inferior sagittal sinus (also known as inferior longitudinal sinus), within the human head, is an area beneath the brain which allows blood to drain outwards posteriorly from the center of the head.
When to use contrast for superior sagittal sinus?
With contrast administration, especially with a CT venogram, then a filling defect in a sinus is sought. Multiplayer reformatted CT venography has been reported with a sensitivity of 95% for this diagnosis 4 . When in the superior sagittal sinus it is referred to as the empty delta sign. Signs on contrast CT include:
Can a CT venogram diagnose distal superior sagittal sinus?
a potential pitfall is interpreting the distal superior sagittal sinus as being hyperdense near the torcular herophili With contrast administration, especially with a CT venogram, a filling defect in the sinus is sought. Multiplanar reformatted CT venography has been reported with a sensitivity of 95% for this diagnosis 4 .
What are the signs of superior sagittal sinus thrombosis?
Potential findings include: cord sign. dense vein sign a potential pitfall is interpreting the distal superior sagittal sinus as being hyperdense near the torcular herophili. the walls at this location can be thick, measuring up to 2-3 mm. cerebral edema: secondary to venous hypertension. cortical/cerebral swelling.
How to diagnose sinus thrombosis with contrast?
With contrast administration, especially with a CT venogram, a filling defect in the sinus is sought. Multiplanar reformatted CT venography has been reported with a sensitivity of 95% for this diagnosis 4 .
