Unusual Venous-Origin Intraparenchymal Hematoma in the Context of a Post-traumatic Carotid-Cavernous Fistula.

Carotid-cavernous fistulas (CCFs) are abnormal connections between the carotid artery and the cavernous sinus. Due to their proximity to the ophthalmic veins, the primary symptoms typically include proptosis, orbital bruit, and chemosis. However, there are a limited number of cases reported in the literature where the clinical presentation is associated with intracerebral hemorrhage. We present a case of a 59-year-old male who sustained a moderate traumatic brain injury in December 2024, resulting in a right temporal hemorrhagic contusion and encephalomalacia without any clinical sequelae. In February 2025, the patient developed a sudden left hemicranial headache, accompanied by generalized epileptic seizures and altered consciousness, prompting emergency admission. A non-contrast cranial computed tomography (CT) scan revealed an intraparenchymal hematoma in the left anterior lenticular region. A cerebral angiotomography was inconclusive. Given the non-contrast cranial CT scan findings, a cerebral panangiography was performed, which revealed a left CCF. The combination of the clinical history and the imaging findings led to the conclusion of a traumatic origin. The fistula was successfully embolized with coils, and the patient showed neurological improvement during recovery. Cavernous sinus arteriovenous fistulas present significant diagnostic and therapeutic challenges in clinical practice. The classification of these fistulas into high-flow and low-flow types, according to the Barrow system, provides an initial framework for understanding their nature and clinical presentation. The clinical manifestations can vary depending on the type of fistula, underscoring the importance of understanding the pattern of venous drainage. Endovascular treatment, considered safe and effective, includes options such as coil embolization through either transarterial or transvenous approaches, which are crucial for the management of these conditions. Alternative endovascular treatment options include deploying a flow diverter, though its results in the literature are debatable, and the use of liquid embolic agents. Parent artery sacrifice is reserved as a last resort when selective closure attempts fail.