Cerebral venous sinus expansion in post-lumbar puncture headache.

Cerebrospinal fluid (CSF) leak at the lumbar puncture (LP) site may induce intracranial hypotension, a common cause of post-LP headache (LPH). We present the case of an 18-year-old man who developed a severe and continuous positional headache 24 hours after LP. CT scan and MRI showed abnormal, intense, dural venous sinus enhancement, indicating a compensatory venous expansion. The patient recovered fully within a fortnight. This report supports the hypothesis that venodilation may be involved in the pathogenesis of LPH. Brain MRI, to detect possible dural venous sinus abnormalities, should therefore be performed in patients with severe and prolonged LPH, as this may allow a prompt recognition and treatment of this disturbing condition.