Sinus thrombosis probably resulting from a dural arteriovenous fistula development in the superior sagittal sinus

A 59-year-old woman developed speech difficulties and was referred to our hospital the next day. She was conscious but showed speech arrest. Physical examination did not show a neurological abnormality or signs of raised intracranial pressure. Laboratory findings, including data for coagulability, were normal. Computed tomography showed a small subcortical haematoma in the left frontal lobe. Angiography of the left internal carotid did not show a source for haemorrhage but showed poor filling in the frontal area and a filling defect of anterior portion of the superior sagittal sinus (SSS) (Fig. i.a). Angiography of the external carotid showed a dural arteriovenous fistula (DAVF) in the SSS fed by middle meningeal arteries (MMAs) on both sides and draining into the SSS through the left frontal deep medullary and cortical veins (Fig. 1.b). Magnetic resonance imaging (MRI). showed a thrombus in the SSS corresponding to the filling defect seen on angiography. It was inhomogeneous on Tl and hyperintense on T2 weighted imaging (Fig. 1.c, d). A craniotomy was done. We interrupted the feeding MMAs, and widely removed and cauterized the dura near the DAVF, in order to prevent growth of collateral feeding pathways. The symptoms gradually subsided. Angiography was repeated 12 days after the surgery and showed disappearance of the DAVF and improvement of venous return in the left frontal region. She was discharged without deficit. MRI three months later showed persistence of the sinus thrombosis, hypo-intense on both T1 and T2 weighted imaging. She has been followed up uneventfully, for one year.