Presentation
Presented to the emergency department with confusion. CT done on call. Proceeded to MRI brain.
Patient Data
Widespread enlargement of the cortical veins in both cerebral hemispheres and posterior fossa, best appreciated on the SWI MIP images. Additionally, there is marked enlargement of the external carotid artery branches, particularly of the scalp and meninges.
Large right transverse sinus, outwardly convex suggesting high flow. Hypoplastic left transverse sinus.
The brain appears swollen with patchy high T2 signal. There is, in addition, tonsilar descent and a moderate amount of periventricular high T2 signal. The lateral ventricular bodies are broad probably due to a non-visualized cavum septum pellucidum or maybe an absent septum (in either case, this is incidental).
No diffusion restriction.
Conclusion:
Features are characteristic of a dural AVF with secondary venous hypertension.
Cerebral angiogram performed - images not available.
Cerebral Angiography Report
Under local anesthesia through right femoral approach cerebral angiogram was done after selective cannulation of right and left carotid and right and left vertebral arteries. Selective cannulation of internal and external carotid arteries performed.
This study shows type D dural fistula in the superior sagittal sinus at the vertex being supplied by meningeal and superficial arteries on both sides, parietal branches of the ACA and ophthalmic via the palpebral branches of upper eye lid.
There is another fistula at the torcula with main feeders from the right occipital artery. There are multiple dilated cortical venous radicals with venous ectasia in the brain draining via cavernous sinuses. The circulation time is prolonged to 14.0 seconds with early filling of the sagittal sinus via fistula.
Conclusion: dural arteriovenous fistulas (dAVF)
Case Discussion
The appearances in this case of widespread cortical vein enlargement along with diffuse T2 periventricular high signal change in in keeping with cerebral venous hypertension.
This should prompt the undertaking of a catether angiogram to assess for a dural AV fistula as was identified in this patient.
For a similar case from our institution: https://radiopaedia.org/cases/dural-arteriovenous-fistula-2.