Abstract
A 57-year-old male developed sudden severe headache and nausea with right retroocular pain. On admission bruit could not be heard and neurological examination revealed mild nuchal stiffness. Computed tomography scan showed marked subarachnoid hemorrhage with a small intracerebral hematoma in the right temporal lobe. Right and left carotid angiograms showed a dural arteriovenous malformation (dAVM) in the right olfactory groove fed by bilateral anterior and posterior ethmoidal arteries. The right olfactory vein was a drainer with a vascular sac draining into the sinuses. Bifrontal craniotomy was performed. Removal of the nidus was abandoned due to its deeply seated location in the olfactory groove, so coagulation of the nidus and clipping of the drainer were performed. On postoperative carotid angiograms the dAVM was not visualized any more. The patient showed no neurological deficit.
From 21 dAVMs of the anterior cranial fossa, the following features can be seen: 1) dominance in male (75%), 2) frequent intracranial hemorrhage (86%), 3) drainage to the pial vein (90%), and 4) associated vascular sac (90%). All these features could be seen in this patient. The associated vascular sac originating from the dilated pial vein as a drainer in this case was thought to be the source of the hemorrhage, for its location was the same as the small hematoma. A blockade of cortical drainage would be effective to protect against intracranial hemorrhage.
