Optical coherence tomography angiography in dural carotid-cavernous sinus fistula

Marcus Ang, Chelvin Sng, Dan Milea

Recently, applications of optical coherence tomography angiography (OCTA) have been limited to the retina and posterior segment. Although early studies have described its use for other clinical applications, its role in anterior segment vasculature and optic disc imaging has been limited thus far. We describe a novel clinical application of OCTA in a patient with dural carotid-cavernous sinus fistula (CCF), which was complicated by increased intra-ocular pressure (IOP). In this case report, we used the OCTA to delineate increased epsicleral venous flow in the affected eye with secondary raised IOP. Current measurements of episcleral venous pressure are either invasive or provide highly variable results, thus the OCTA may have the potential to provide a more reliable approach to assess episcleral vasculature. We also describe the use of OCTA to detect early glaucomatous nerve damage, associated with focal reductions in peripapillary retinal perfusion. We present an early report of using OCTA of the anterior segment to allow rapid, non-invasive delineation of abnormal episcleral venous plexus secondary to dural CCF. The OCTA was also useful for detecting early reduction in peripapillary retinal perfusion, which suggests early glaucomatous optic neuropathy. This suggests that OCTA may have a role for determining risk of glaucoma in patients with CCF in future.