Cortical Venous Thrombosis

KEY FACTS

TERMINOLOGY

• Cortical/cerebral venous thrombosis (CVT)

• Dural sinus thrombosis (DST)

• CVT with DST > isolated CVT without DST

IMAGING

• NECT

○ Cord sign (hyperdense vein)

○ Involved veins usually enlarged (distended with clot),

irregular

○ ± petechial parenchymal hemorrhage, edema

• CECT

○ If DST, empty-delta sign (25-30% of cases)

○ CTV: Thrombi may be seen as filling defects

• MR

○ Acute thrombus isointense on T1WI

○ Hypointense on T2WI (can mimic flow void)

○ T2* GRE best (clot usually blooms)

• 2D time of flight MRV

○ Thrombus seen as sinus discontinuity, loss of vascular

flow signal

○ Subacute thrombus T1 hyperintense (mimics patent flow

on maximum intensity projection)

• Imaging recommendations

○ NECT, CECT scans ± CTV

○ If CT negative → MR/MRV with T1WI C+, GRE

○ If MR is equivocal → DSA (gold standard)

TOP DIFFERENTIAL DIAGNOSES

• Normal (circulating blood slightly hyperdense)

• Anatomic variant (hypoplastic segment can mimic DST)

CLINICAL ISSUES

• Most common symptom is headache

• Seizure

DIAGNOSTIC CHECKLIST

• If "convexal" subarachnoid hemorrhage is seen, consider

CVT

(Left) Autopsy case shows

thrombus in several cortical

veins ſt, the pathologic basis

for the cord sign. (Courtesy

E.T. Hedley-Whyte, MD.)

(Right) Axial NECT scan in a

patient with thrombosis of the

superior sagittal sinus shows

dense clot ſt filling and

expanding of the superior

sagittal sinus. Thrombus is

seen in a vein ﬇ over the

cerebral convexity. Most (but

not all) cortical vein thrombi

occur as extension from clot in

an adjacent dural venous

sinus.

(Left) Autopsy case of

transverse sinus thrombosis

﬈ that occluded the vein of

Labbé shows extensive

hemorrhagic venous infarction

of the temporal, parietal, and

occipital lobes ﬇. (Courtesy

R. Hewlett, MD.) (Right) This

23-year-old woman presented

in the ER with "migraine

headache." Initial NECT scan

(L) was called normal. Note

the hyperdense thrombus in

left TS ſt. CT 1 day later

(right) shows vein of Labbé

thrombosis st and a large left

temporal lobe hemorrhagic

venous infarct ﬇.

Brain: Pathology-Based Diagnoses: Malformations,

Trauma, and Stroke

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