POSTCONTRAST DURAL MR ENHANCEMENT AND ACUTE CSF INTRACRANIAL HYPOTENSION

Diffuse abnormal dural enhancement is an increasing finding on MR studies and has a wide differential diagnosis (1). Low-CSF-pressure states are one of the causes, for which the proposed mechanisms are meningeal hyperemia, inflammation, and fibrocollagenous proliferation in the dura. These low-pressure states are either spontaneous or iatrogenic (lumbar puncture, craniotomy, ventricular shunts) and can be asymptomatic (2) or lead to postural headaches (3). In most cases the presence of a persistent leak of CSF or shunt overdrainage leads to a subacute or chronic low-pressure state. The diffuse enhancement pattern found in contrast-enhanced MR studies is probably due to a fibrocollagenous proliferation in the dura that usually disappears slowly after restoration of CSF pressure. We present an unusual case of a patient with an acute low-CSF-pressure state induced by a massive drainage of CSF through a lumbar puncture, in which contrast-enhanced brain MRI showed diffuse dural enhancement that completely disappeared after restoration of CSF pressure. © 1995 Lippincott-Raven Publishers, Philadelphia.