Cerebral MR venography: normal anatomy and potential diagnostic pitfalls

Area of Science:

• Radiology
• Neuroimaging
• Vascular Imaging

Background:

• MR venography is a key tool for evaluating the intracranial venous system.
• Dural sinus thrombosis is a significant concern requiring accurate diagnostic methods.

Purpose of the Study:

• To assess MR venography's depiction of normal intracranial venous anatomy and variants.
• To identify potential pitfalls in diagnosing dural venous sinus thrombosis using MR venography.
• To compare MR venography findings with conventional catheter angiography.

Main Methods:

• Review of cerebral MR venograms from 100 individuals with normal MR imaging.
• Assessment for the presence or absence of dural sinuses and major intracranial veins.

Main Results:

• Transverse sinus flow gaps were found in 31% of normal studies, predominantly in nondominant sinuses.
• Superior sagittal and straight sinuses were consistently visualized.
• Occipital sinus visualization was infrequent (10%), while major deep veins like the vein of Galen were always seen.

Conclusions:

• A significant percentage of normal MR venography studies exhibit transverse sinus flow gaps.
• These flow gaps can mimic pathology and should not be mistaken for dural sinus thrombosis.
• Understanding these normal variants is essential for accurate interpretation of MR venography in suspected dural venous sinus thrombosis.