Objective: In cavernous sinus dural arteriovenous fistula (CSdAVF), multiple shunt points are often demonstrated on the angiogram. In some cases, shunt points may be located not only at the CS itself but at the part surrounding the CS. We report a rare case of CSdAVF with a shunt at the diploic vein of the orbital roof (DVOR).
Case Presentation: A 64-year-old man presented with exophthalmos, conjunctival injection, and abducens nerve palsy. The shunt points were suspected to be located at the anterior lateral part and posterior medial part of the left CS on the angiogram and the drainage route was the left superior ophthalmic vein (SOV) and the veins of the posterior fossa via the left petrosal vein. We embolized the suspected shunt points in the CS transvenously. Another shunt point was identified anterior to the CS by superselective angiography. By meticulous review of the angioarchitecture, using 3D rotational angiography and multi-planar reconstruction (MPR) images, another shunt point was found at the DVOR fed by branches of the ophthalmic artery and sphenopalatine artery branches.
Conclusion: We report a case of CSdAVF with multiple shunt points including a shunt located at the DVOR. To the best of our knowledge, this is the first case report with CSdAVF with a shunt point at the DVOR. In cases of CSdAVFs, careful analysis of the angioarchitecture using 3D rotational angiography, MPR images, and superselective angiography is necessary to elucidate the presence of shunts in rare locations.
