Scalpel sign (spinal cord)

Last revised by Rohit Sharma on 3 Apr 2024

The scalpel sign is described in dorsal thoracic arachnoid web on sagittal MRI spine studies. It relates to focal distortion of the thoracic cord, appearing anteriorly displaced. The enlarged dorsal CSF space mimics the profile of a surgical scalpel.

It is helpful in distinguishing cases where the thoracic cord is focally anteriorly displaced, a finding seen in a couple of other conditions in addition to dorsal thoracic arachnoid web 2, namely ventral cord herniation and the presence of a dorsal arachnoid cyst.

ADVERTISEMENT: Supporters see fewer/no ads

Updating… Please wait.

 Unable to process the form. Check for errors and try again.

 Thank you for updating your details.