Cervical MR imaging in postural headache: MR signs and pathophysiological implications.

Abstract

The MR signs of dilatation of the venous plexus, presence of spinal hygromas, and presence of retrospinal fluid collections can help to establish the diagnosis of intracranial hypotension. They are probably the result of decreased CSF volume, with the retrospinal fluid collections being a transudate from the venous plexus rather than frank extravasation. Resolution of these signs parallels resolution of the headache.