A Case of Direct Carotid-Cavernous Fistulae Successfully Treated by Bidirectional Double Catheter Technique: A Technical Note

Abstract

Objective: Ruptured carotid-cavernous aneurysms (CCAs) are known to result in direct carotid-cavernous fistula (CCF). Although endovascular treatment is recognized as the first-line treatment for direct CCF, obliteration is sometimes difficult because of the high-flow shunt. In this report, we present a case of a direct CCF treated by the combination of transarterial and transvenous approaches.

Case presentation: A 57-year-old woman presented with conjunctival chemosis, exophthalmos, and tinnitus. Ophthalmological examination revealed increased intraocular pressure. DSA demonstrated a direct CCF due to a right ruptured CCA with retrograde shunted flow through the superior ophthalmic vein (SOV), superficial middle cerebral vein, basal vein of Rosenthal, and middle temporal vein. Two microcatheters were guided into the shunt segment from the internal carotid artery and SOV. In addition, a balloon catheter was placed at the neck of the aneurysm to assist coiling. Coil embolization for the CCF was performed using two microcatheters in the opposite direction, which enabled compact and tight packing of the shunt segment with only six coils. The CCF was eliminated. Two-year-follow-up MRA revealed no recurrence.

Conclusion: The bidirectional double catheter technique is a useful approach to obliterate a shunt in a short segment with minimal coils.

Keywords: direct carotid-cavernous fistula; transarterial embolization; transvenous embolization.

Fig. 1. MRI on admission. Time-of-flight-MRA on admission shows enlargement of the SOV and significant flow signal at the right cavernous sinus. The CCA is indicated by an arrow. CCA: carotid-cavernous aneurysm; SOV: superior ophthalmic vein

Fig. 2. DSA at diagnosis. (A and B) Arterial phase of initial right ICA angiography, anteroposterior (A) and lateral (B) views, showed a high-flow shunt at the cavernous sinus draining into the SOV (black arrow) and SMCV (white arrow). Furthermore, severe stenosis at the curve of an angular vein draining to the facial vein was revealed (white arrowhead). (C) DSA at the working angle to visualize the CCA clearly. The dotted line traces the contour of the aneurysm. White arrows indicate the shunt segment. (D) Late arterial phase on right ICA angiography showing cortical venous reflux with a pseudophlebitic pattern. (E) Early venous phase on right ICA angiography revealed venous drainage to the contralateral basal vein of Rosenthal (white arrowheads) and middle temporal vein (black arrows). CCA: carotid-cavernous aneurysm; ICA: internal carotid artery; SMCV: superficial middle cerebral vein; SOV: superior ophthalmic vein

Fig. 3. Intraoperative angiography. (A and B) Working angle on right ICA angiography during the procedure, viewed from the left cranial projection (LAO 90 degree, Cranial 27 degree). The two microcatheters navigated to the fistula and intracranial balloon catheter (arrow) are shown in (B). Solid line: XT17 from the ICA. Dotted line: SL10 from the SOV. (C) Venous phase at the same working angle. Right ICAG after navigating the distal access catheter and microcatheter through the right SOV (black arrows) revealed sufficient venous drainage via the contralateral SOV (white arrows) to the cavernous sinus (white arrowhead) instead of the stagnant angular vein (black arrowheads). (D) The shunt segment is completely embolized with seven coils. (E) Right IC angiography, anteroposterior (E) and lateral (F) views, showed extirpation of the shunted flow. (G) Follow-up MRA 2 years after the procedure showed no recurrence of the aneurysm or the shunt. IC: internal carotid; ICA: internal carotid artery; ICAG: internal carotid angiography; LAO: left anterior oblique; SOV: superior ophthalmic vein