Presentation
83M who presented with orbital congestion
Diagnosis
- Carotid-cavernous fistula of the left internal carotid artery.
- Left post septal cellulitis and myositis causing mild left globe proptosis.
Key Findings
Incidental findings
Discussion
- Time-of-flight (TOF) MRA shows arterial flow signal within the left cavernous sinus and an asymmetrically enlarged left superior ophthalmic vein, consistent with a carotid-cavernous fistula (CCF) most likely arising from the left internal carotid artery.
- Partially visualized smooth pachymeningeal enhancement overlying the left anterior and middle cranial fossa. Possible etiologies include abnormal flow-related enhancement due to ipsilateral CC fistula or less likely meningeal infection/inflammation.
- CCFs can be classified as either direct (usually the result of trauma) or indirect (can be related to Ehlers-Danlos or fibromuscular dysplasia)
- TOF angiography is way to image vessels without the use of contrast An excellent review on the physics of TOF can be found here: youtube.com/watch?v=kBrLUaEJaLU.