Traumatic Dissection, Carotid–Cavernous Fistula & Penetrating Injury

Look Beyond the Initial Hematoma

The TBI outline includes arterial dissection, carotid–cavernous fistula, and penetrating injury. Their important feature is a mismatch between mechanism or examination and a routine noncontrast head CT. A patient can have an injured cervical artery before an infarct becomes visible, or an abnormal fistula causing orbital venous hypertension without a large intraparenchymal hemorrhage. Repeated neurologic and ocular examination therefore remains useful after the initial resuscitation.

Begin with airway, oxygenation, hemorrhage control, cervical stability, and the broader trauma survey. Once immediate threats are addressed, determine whether the mechanism, fractures, wound path, or unexplained deficits warrant CTA or other vascular imaging under the trauma team's screening protocol. Do not assume that a patient without neck pain has intact cervical arteries; coma and sedation may make symptoms unavailable.

Blunt Cerebrovascular Injury

Blunt cerebrovascular injury (BCVI) includes carotid and vertebral injuries after stretching, compression, rotation, or direct impact. An intimal tear can produce mural hematoma, luminal narrowing, intraluminal thrombus, pseudoaneurysm, occlusion, or transection. Stroke may be delayed because embolization or progressive thrombosis occurs after the initial event.

High-risk cervical spine or skull-base injuries, neck trauma, and focal deficits unexplained by the brain imaging can prompt screening. Use a systematic local protocol rather than remembering only a single fracture type. CTA is commonly the first study. Equivocal findings may require repeat imaging or conventional angiography according to the clinical situation.

EAST recommends antithrombotic therapy for diagnosed BCVI when the clinical situation permits. The exact drug and timing depend on hemorrhage stability, other procedures, and competing risks. Antiplatelet therapy and anticoagulation are not interchangeable in every circumstance, but a concurrent TBI does not mean BCVI should automatically remain untreated indefinitely. Discuss the balance among trauma, neurosurgical, and stroke teams. Routine stenting is not recommended for every intermediate-grade injury; selected lesions require individualized intervention and follow-up.

Carotid–Cavernous Fistula

A direct carotid–cavernous fistula can follow traumatic disruption of the intracavernous internal carotid artery into the cavernous sinus. High-pressure arterial flow produces venous congestion. Findings include pulsatile proptosis, chemosis, an orbital bruit, raised intraocular pressure, diplopia, and cranial nerve palsies. The abducens nerve is particularly vulnerable within this region, but the full pattern depends on anatomy and drainage.

CTA or MRA can suggest the lesion; conventional angiography defines the fistula and venous drainage and can support treatment planning. Vision-threatening congestion, cortical venous reflux, or other dangerous features warrant prompt neurovascular and ophthalmic assessment. Management often uses endovascular techniques tailored to preserve necessary arterial flow while closing the abnormal connection. Do not treat an orbital bruit and progressive chemosis as ordinary postoperative swelling without investigating the vascular mechanism.

Distinguish a direct traumatic fistula from lower-flow dural fistulas, cavernous sinus thrombosis, orbital infection, and other causes of proptosis. Fever or systemic infection shifts the differential, while the trauma mechanism and pulsatility support a high-flow connection. Several processes can coexist after a severe facial injury.

Penetrating Brain Injury

Penetrating injury adds risks of vascular disruption, retained material, contamination, infection, CSF fistula, and early seizures. Assess wound trajectory and intracranial involvement with appropriate CT and vascular studies. Some traumatic vascular lesions can evolve or be missed initially, so follow-up imaging may be necessary depending on wound path and initial findings. Metallic fragments also change MRI safety; composition and location must be assessed before entering the scanner.

Do not remove an impaled object casually in the emergency department. It may be tamponading bleeding, and extraction requires a coordinated operative plan. Manage contamination, tetanus status, wound care, antimicrobial prophylaxis where indicated by the specialist protocol, and seizure prevention without inventing one universal regimen for every trajectory. Avoid unnecessary aggressive retrieval of deep fragments when the procedural damage may exceed benefit; surgical decisions depend on accessible devitalized tissue, mass lesions, contamination, and vascular risk.

A useful vignette is delayed hemiparesis after cervical trauma with an initially unchanged head CT. The appropriate next question is whether the neck vessels and cerebral circulation have been assessed. In a separate case, pulsatile orbital congestion after skull-base injury suggests a fistula and calls for neurovascular evaluation rather than empiric osmotherapy alone.

Source checked October 17, 2026: EAST BCVI guideline and ACS TBI guidance.