TRIPASS XR تري باس

 

– 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

DMCV/BVR to VofG

Anatomy Relationships

• Dural venous sinuses

○ Communicate with extracranial veins directly (via diploic

veins in calvarium, emissary veins through basilar

foramina)

○ Receive venous blood from superficial (cortical) veins,

deep (subependymal) veins

• Cerebral veins

○ Superficial (cortical) veins lie in SAS, mainly follow sulci

○ Subependymal veins outline ventricles

IMAGING ANATOMY

Overview

• Dural venous sinuses

○ Visualization at DSA varies widely

– Almost always: SSS, SS, TS, sigmoid sinus, IJVs

– Sometimes: ISS, SPS/IPS

– Rare/inconstant: CS, sphenoparietal sinus, occipital

sinus, clival (basal) venous plexus

• Cerebral veins

○ Superficial cortical veins almost always seen (number,

configuration vary)

○ Deep veins almost always seen on late venous phase of

DSA, only largest (e.g., thalamostriate veins) seen on

MR/MRV

○ ICVs, VofG almost always seen on DSA, CTV, MRV

ANATOMY IMAGING ISSUES

Imaging Recommendations

• 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

Imaging Pitfalls

• 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

(pseudolesion)

• Unopacified venous blood streaming into dural sinus on

DSA should not be mistaken for filling defect (thrombus)

• "Giant" arachnoid granulations appear as round/ovoid CSFequivalent filling defects in dural sinuses (especially TS), are

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

enhancement)

Trauma, and Stroke

Brain: Pathology-Based Diagnoses: Malformations,

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