Acute confusional syndrome from a dural arteriovenous fistula

We describe a case of an acute confusional state associated with a right parietal dural arteriovenous fistula. A 67-year-old man in his usual state of health experienced an acute confusion episode preceded by a valsalva maneuver. The episode lasted approximately 60 minutes. Afterward he was able to remember everything that occurred. A magnetic resonance imaging scan suggested a right parietal dural arteriovenous fistula, which was confirmed by angiography. A seizure was ruled out by clinical examination and an electroencephalogram. The patient underwent therapeutic embolization and surgical ligation of the fistula. Feeding vessels to the malformation were cauterized within the leaves of the falx, and the draining vein was clipped with a titanium aneurysm clip and divided. An intraoperative angiogram was then performed, which showed obliteration of the fistula. There was no demonstrable confusion or memory loss noted postoperatively. We propose that venous hypertension from the dural arteriovenous fistula in combination with a valsalva maneuver caused ischemia in the right parietal lobe, eliciting a deficit in attention.