Rapid cognitive decline following lumbar puncture in a patient with a dural arteriovenous fistula.

BACKGROUND

Dural arteriovenous fistulas (DAVFs) are frequently accompanied with raised intracranial pressure and clinical findings suggestive of pseudotumor cerebri. However, unlike pseudotumor cerebri, the clinical response to lumbar cerebrospinal fluid (CSF) removal can vary from beneficial to acute clinical deterioration leading to death. The criteria for the safe use of lumbar puncture (LP) in patients with a DAVF are not well established.

METHODS

A 61-year-old man presented with visual difficulty. Magnetic resonance imaging (MRI) and angiography revealed a left transverse sinus DAVF. He underwent multiple embolizations of arterial feeders over 3 years. He was then noted to have cognitive deficits in short term memory, listening, and concentrating. Over several days after an LP he became increasingly lethargic but arousable. Within hours after a repeat LP there was a rapid deterioration in the patient's level of consciousness and he became unarousable.

RESULTS

A brain MRI revealed extensive dilated cortical veins and left temporal lobe venous ischemia without tonsillar herniation. A cerebral angiogram showed an extensive left transverse sinus DAVF with an occluded lateral transverse sinus and increased retrograde venous drainage. Embolization of the arterial feeders in combination with trans-venous coil embolization of the left transverse sinus reversed the patient's neurologic decline. He was discharged neurologically intact except for his chronic visual acuity problems.

CONCLUSION

We speculate that when a DAVF manifests retrograde venous flow sufficient to cause cognitive deficits, lumbar CSF drainage must be undertaken with extreme caution.