Tentorial dural fistulas: endovascular management and description of the medial dural-tentorial branch of the superior cerebellar artery

Abstract

Background and purpose: TDAVFs are uncommon causes of spontaneous intracranial hemorrhage. A retrospective review of their management was performed after repeatedly observing a previously under-recognized medial dural-tentorial branch of the SCA.

Materials and methods: Thirteen patients were diagnosed with TDAVFs by CT/MR imaging and DSA during a 5.8-year period. Seven patients presented after intracranial hemorrhage. Twelve patients were treated endovascularly, and one, surgically.

Results: Eleven TDAVFs were located in the midline (7 at the falx cerebelli and 4 at the torcular), and 2 were petrotentorial. All torcular TDAVFs were associated with sinus thrombosis and showed bidirectional drainage relative to the tentorium. No sinus thrombosis was seen in the falx cerebelli subtype, which drained infratentorially only, except in 1 patient who had had unrelated surgery previously. Venous drainage was directly to cortical veins except for 1 petrotentorial and 2 torcular TDAVFs. A branch of the SCA, the medial dural-tentorial artery, was observed in 5 midline TDAVFs. Its anatomy was defined with selective angiography. Endovascular therapy resulted in a cure in 5 and subtotal occlusion in 6, and staged treatment is ongoing in 1 patient. One patient was cured after surgery.

Conclusions: TDAVFs frequently cause intracranial hemorrhage and therefore warrant treatment. Endovascular therapy proved effective in this series, and arteriography was essential for understanding the various fistula subtypes and for treatment planning. We emphasize the importance of recognizing the medial dural-tentorial artery of the SCA with its characteristic course along the tentorium on angiography. This artery should be included in future anatomic descriptions of the cranial blood supply.

Fig 1.

Sites of TDAVFs: 1 = falx cerebelli, 2 = torcular, and 3 = petrotentorial locations.

Fig 2.

Torcular TDAVF (patient 8). Injections of the right vertebral artery in the lateral (A) and anteroposterior (B) views. Note the medial dural-tentorial branch of the left SCA (white arrow) running below the ADS (black arrow); both arteries are supplying the fistula. Additional supply is seen from the posterior meningeal artery and muscular branches of the extracranial vertebral artery.

Fig 3.

Torcular TDAVF (patient 7). Injections into the left vertebral artery in lateral (A) and the right vertebral artery in lateral-oblique (B) views show the supply to the fistula from the left ADS (black arrows) and the left medial dural-tentorial branch of the SCA (white arrows). There was additional arterial supply from branches of the external carotid artery (not shown).

Fig 4.

Falx cerebelli TDAVF (patient 1). Injections of the left vertebral artery in anteroposterior (A) and lateral (B) views and superselective injection of the ADS (C) and medial dural-tentorial branch of the SCA (D). The fistula supply arises from the left ADS (black arrow) and left medial dural-tentorial branch of the SCA (white arrow). The asterisk marks a connection between these 2 arteries within the tentorium.

Fig 5.

Falx cerebelli TDAVF (patient 2). Injections of the left vertebral artery in lateral (A) and anteroposterior (B) views. Arterial supply to the fistula arises, among others, from the medial dural-tentorial branch of the right SCA (white arrows) and the right posterior meningeal artery (black arrows). Additional supply from branches of the external carotid artery and the marginal tentorial artery are not shown.