Dural sinus malformation presenting with proptosis: report and review of a rare entity.

Dural sinus malformation (DSM) is a rare vascular malformation characterized by the dilatation of a dural venous sinus with or without an anomalous jugular bulb. Its presentation with venous-reflux-related secondary proptosis is anecdotal, with only six such cases reported so far. We report a 17-month-old boy who presented with a progressive proptosis of the right eye secondary to a DSM of the transverse sinus and torcula. Following endovascular embolization of the arterio-venous fistula, complete thrombosis of the venous lake and improvement in proptosis was noted at 6-month follow-up. Prognosis of this rare malformation is variable and dependent on specific angio-architectural features.