Supraclinoid direct carotid-cavernous sinus fistula.

Area of Science:

• Neurology
• Vascular Surgery
• Radiology

Background:

• Carotid-cavernous fistulas (CCFs) involve abnormal shunts between the carotid artery and the cavernous sinus.
• Direct CCFs are often linked to head trauma, typically involving tears in the cavernous segment of the internal carotid artery.
• Tears in the supraclinoid segment of the internal carotid artery are an uncommon cause of CCF.

Purpose of the Study:

• To report a rare case of a direct carotid-cavernous fistula.
• To describe an internal carotid artery supraclinoid segment pseudoaneurysm as the source of the fistula.
• To illustrate an atypical mechanism of CCF formation and venous drainage.

Main Methods:

• Case report detailing a patient with a rare vascular anomaly.
• Review of diagnostic imaging findings, likely including angiography.
• Description of the anatomical location and characteristics of the pseudoaneurysm and fistula.

Main Results:

• Identification of a pseudoaneurysm in the supraclinoid segment of the internal carotid artery.
• Demonstration of a direct arteriovenous shunt from the pseudoaneurysm into the cavernous sinus.
• Confirmation of venous drainage into the superior ophthalmic vein.

Conclusions:

• Supraclinoid internal carotid artery pseudoaneurysms can rarely cause direct carotid-cavernous fistulas.
• This case expands the understanding of etiological factors and anatomical variations in CCF.
• Highlights the importance of considering rare arterial pathologies in the diagnosis of CCF.