Cortical vein sign

The cortical vein sign refers to the presence of superficial cortical veins seen on MRI and CT (particularly with contrast injection) traversing the subarachnoid space that differentiates it from the similar radiological appearance of a subdural hygroma.

Although initially proposed as a method for differentiating cerebral atrophy from subdural hygroma 1, this sign is also valid for differentiating benign enlargement of the subarachnoid spaces in infancy from subdural hygroma (which may be a sign associated with non-accidental injury2,3. In infants, an ultrasound Doppler study of the cranium, instead of brain CT or MRI, can also be used to detect the presence of these cortical veins 2,3.

The mechanism behind this sign is that in global cerebral atrophy or benign enlargement of the subarachnoid spaces in infancy, the cortical veins will still be adjacent to the inner table of the calvarium and thus visible traversing the subarachnoid space with MRI, CT or ultrasound Doppler 1-3. While in a subdural hygroma, the veins are displaced away from the inner table because the arachnoid membrane and subarachnoid space are displaced by the subdural fluid collection 1-3.

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Article information

rID: 54022
Section: Signs
Synonyms or Alternate Spellings:

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Cases and figures

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    Case 1: presence of veins (arrows) in BESSI
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    Subdural Hygroma ...
    Case 2: lack of veins in subdural hygroma
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