Intracranial dural AV fistula- An unfolding enigma
An Intracranial dural arteriovenous fistulas (DAVF), is an abnormal direct connection (fistula) between a meningeal artery and a meningeal vein or dural venous sinus &/ cortical vein 1. When there are multiple fistulas they are termed as dural arteriovenous malformations and comprise 10-15% of all intracranial arteriovenous malformations1.
Here we present a case of52yr old patient who presented to our casualty with history of sudden onset of headache, giddiness, and vomiting, followed by loss of consciousness. Neurological examination revealed impairment of consciousness, no verbal response, with left hemiparesis (E2V1M5). Bilaterally, pupils were 5mm and sluggishly reacting to light. Vitals were stable with B.P. recording of 140/80 mm of hg, and a pulse rate of 80 /min. Pre contrast CT scan showed an intraparenchymal haemorrhage with perilesional oedema in the right frontal region.
CT angiography brainshoweda intracranial dural AVF with varix and adjacent intraparenchymal haemorrhage.
D.S.A. revealed a Borden type III & Cognard type IV –midline dural Arteriovenous fistula in the regionofmid superior sagittal sinus and along the cerebral falx, with a large venous ectasia/varix along the anterior cerebral falx.
Management: Patient underwent afronto parietal rectangular craniotomy Right posterior frontal, parasagittal engorged bunch of focal cortical veins was cauterized. Underlying haematoma was evacuated and the underlying venous ectasia/ varix identified. It was found to be thrombosed. A large draining vein was found which was clipped and any consequent brain swelling was looked for, before finally excising it in toto.
Post –op period was uneventful, with the patient gradually improving in sensorium with residual hemiplegia and aphasia.
Although recent developments in catheter interventionhas made it the preferred option in most of the cases, surgery is still preferred in some select cases.
Keywords:Intracranial dural AV fistula, Superior sagittal sinus, Cognard and borden classification, CT andiography, Digital subtraction angiography