[Reconstruction of the venous outflow using a vein graft in dural arteriovenous malformation associated with sinus occlusion].

In some cases of dural arteriovenous malformations (dural AVMs) of the transverse-sigmoid sinuses, the presence of an occlusion or hypoplasia on the sinus contralateral to the affected side may significantly contribute to the development of intracranial hypertension. For these cases, closure of AV shunts or removal of the affected sinus may not be sufficient to improve intracranial hypertension. We encountered 2 cases of intracranial hypertension caused by dural AVMs at the transverse-sigmoid sinuses associated with disturbance of venous outflow contralateral to the lesion. Reconstruction of venous outflow using a saphenous vein graft was performed between the transverse sinus and the subclavian or external jugular vein after the dural AVMs were partially occluded by catheter embolization. Intracranial hypertension was relieved in both cases. In one case dural AVM was obstructed by both embolization and radical surgery after the bypass was confirmed unobstructed several weeks later. The bypass remained patent at the follow-up 4 months later. In the other case, patency of the bypass lasted only for approximately 1 month. In both cases clinical improvements were not remarkable. It is considered that the presence of AV shunt in the case of dural AVM may facilitate the patency of a graft placed between the venous systems. Reconstruction of the venous outflow may deserve further trial for the treatment of intracranial hypertension associated with some types of dural AVM.