SPONTANEOUS HIGH FLOW CAROTID-CAVERNOUS SINUS FISTULA CONFIRMED FROM DIGITAL SUBTRACTION ANGIOGRAPHY: A VERY RARE CASE

Background: Carotid cavernous fistula (CCFs) is characterized by an aberrant channel linking the carotid artery directly to the cavernous sinus. Most of the CCFs are classified as traumatic CCFs, which is occurred following trauma. Meanwhile spontaneous CCFs, which is occurred spontaneously, are very rare. Spontaneous CCFs typically occur in elderly women and are usually classified as low-flow, indirect fistulas of Barrow type D. This study aimed to present a rare case of a spontaneous high-flow CCFs classified as Barrow type A, due to its uncommon occurrence. Case presentation: A 56-years-old woman came fully alert presented with swelling and redness on the right eye since 1-month prior admission. Palpebral edema, episcleral injection, conjunctival chemosis, proptosis, and bruit were found from her right eye. CT-angiography found engorgement on the right cavernous sinus with superior ophthalmic vein (SOV) dilatation. The RICA DSA revealed that the contrast filled the cavernous sinus, SOV, facial vein, and internal jugular vein on the early artery phase, which indicates a high flow CCFs at the C4 with Barrow classification type A. The patient was planned for fistula embolization with coil. Conclusion: Spontaneous high flow CCFs is an extremely rare condition. Accurate history taking and thorough physical examination are essential to identify the classic triad of CCFs symptoms: proptosis, chemosis, and ocular bruit. The definitive diagnostic tool is a cerebral angiogram, which can reveal the presence of a fistula by demonstrating contrast filling of the cavernous sinus.