Carotid-Cavernous Fistula

Carotid-Cavernous Fistula
SYMPTOMS Orbital pain/pressure | diplopia | swishing sound | headaches | rarely vision loss
SIGNS Pulsatile proptosis | Horner’s syndrome | EOM restrictions | dilated (corkscrew) conjunctival and episcleral vessels | chemosis | elevated IOP | tortuous retinal veins | vein occlusions | papilledema | retinal hemorrhages
DIRECT carotid-cavernous fistulas (usually high flow and caused by trauma) are more likely to present with signs and symptoms than INDIRECT carotid-cavernous fistulas (usually low flow and occur spontaneously)
WORK-UP Thorough history | Pupils | EOMs | Slit lamp examination | Dilated retinal examination | Exophthalmometry | Check for orbital bruit (Ocular auscultation)
TREATMENT Refer to a neuro-ophthalmologist STAT for additional testing and treatment. Treatment is usually conservative but surgery is an option: surgical resection, radiation therapy, or embolization
FOLLOW-UP Depends on severity. A multi-disciplinary approach is warranted (neurology, oculoplastics, etc.). After seeing neuro-ophthalmogist, patients should be followed every 6-12 months.
ADDITIONAL LAB | TESTS CT | CTA | MRI of the brain and orbits with and without contrast | MRA | Digital Subtraction Angiography (DSA) is the gold standard.
ETIOLOGY Abnormal connections between the carotid artery and venous channels of the cavernous sinus. Can occur spontaneously or secondary to trauma or surgery.
DIFFERENTIAL DX Thyroid eye disease | idiopathic orbital inflammatory syndrome | cavernous sinus thrombosis | superior orbital fissure syndrome | retrobulbar hemorrhage | orbital apex syndrome.
NOTES Improvement in ocular signs and symptoms typically occurs shortly after treatment.
Posted in Ocular Conditions, Orbit