Another way, perhaps intense-looking, but rational and quite effective, to get into the cavernous sinus when other routes are not looking promising.
Patient presents with proptosis, chemosis and progressive loss of right eye vision. Angiogram shows slow flow right cavernous sinus (white arrows) dural fistula supplied by the right MHT and ILT. Drainage is exclusively into the superior ophthalmic vein (SOV).
Even though the fistula is small and “slow”, the problem is that the SOV does not appear to have adequate drainage. Normally of course SOV drains into the cavernous sinus. Here, the flow is reversed because of fistula-related congestion. However, the usual outflow in such cases into the angular/facial/infraorbital veins is not present. Hence intense venous congestion of the orbit and symptoms despite “slow” fistula. Once again, example of how dural fistulas are nearly always venous congestion diseases.
What to do? Direct puncture of superior ophthalmic vein at the orbital apex, best accomplished from inferior lateral approach, directing the needle inferiorly and walking along the bony orbit until target is reached (remember the disclaimer section). Puncture with any kind of long enough needle that will take an 017 microcatheter. In this case we have a generic 18 gauge “Seldinger” needle.
Roadmap (top) and DSA views of direct injections
A microcatheter is placed into the posterior portion of the cavernous sinus, followed by detachable coil embolization.
(Man buys woman two dresses – red and blue. Next day man sees woman wearing red dress and asks what’s wrong with the pretty blue one. In other words, don’t ask why not Glue or Onyx)
After last coil
Additional literature on this infrequent however so far quite safe and effective approach
See companion case of another slow flow cavernous sinus dural fistula presenting with vision loss, cured by nBCA embolization of the MHT here