– Posterior/inferior temporal lobe, adjacent parietal
lobe drained by vein of Labbé to TS
– Insular cortex, parenchyma around sylvian (middle
cerebral) fissure drained by sphenoparietal sinus to CS
– Deep cerebral structures (central/deep white matter,
basal ganglia) drained by medullary/subependymal
veins to ICVs, VofG, SS; medial temporal lobe via
○ Communicate with extracranial veins directly (via diploic
veins in calvarium, emissary veins through basilar
○ Receive venous blood from superficial (cortical) veins,
○ Superficial (cortical) veins lie in SAS, mainly follow sulci
○ Subependymal veins outline ventricles
○ Visualization at DSA varies widely
– Almost always: SSS, SS, TS, sigmoid sinus, IJVs
– Rare/inconstant: CS, sphenoparietal sinus, occipital
sinus, clival (basal) venous plexus
○ Superficial cortical veins almost always seen (number,
○ Deep veins almost always seen on late venous phase of
DSA, only largest (e.g., thalamostriate veins) seen on
○ ICVs, VofG almost always seen on DSA, CTV, MRV
• Obtain source images for MR venogram perpendicular to
main axis of dural sinus (e.g., coronal for SSS)
• MRV, CTV excellent for general overview of dural sinuses,
cerebral veins but DSA best for detailed delineation
• TSs often asymmetric, hypoplastic/atretic segment
common (do not misdiagnose as occlusion)
• Saturation bands on MR disguise flow
• Jugular bulb flow often very asymmetric, turbulent
• Unopacified venous blood streaming into dural sinus on
DSA should not be mistaken for filling defect (thrombus)
normal variant, should not be mistaken for thrombus
• Acute dural sinus, cortical vein thrombi isointense with
brain on T1WI, so T2* (GRE) or T1 C+ imaging very helpful
• Subacute clot is hyperintense on T1WI (do not mistake for
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