A case of ultrasound-guided intrasac thrombin injection for iatrogenic femoral artery pseudoaneurysm

We report a case of femoral artery pseudoaneurysm (FAP) following endovascular embolization of a carotid aneurysm, successfully treated with ultrasound-guided percutaneous thrombin injection (UGTI). A 67-year-old woman developed FAP (3.85×3.92×2.64 cm) postoperatively, with initial compression therapy failing to resolve the lesion. Multidisciplinary team consultation led to UGTI, employing thrombin’s coagulation cascade to induce thrombosis, occluding the aneurysm neck. The procedure involved slow tranexamic acid injection under ultrasound guidance, resulting in complete thrombosis (anechoic-to-isoechoic transition) and resolution of blood flow on follow-up imaging. Notably, the pseudoaneurysm regressed significantly (5.02×1.98 cm) within two days, with sustained recovery at one month. This case highlights UGTI’s efficacy as a minimally invasive, rapid-response alternative to surgical repair, particularly for compression-refractory FAPs. The innovative use of real-time ultrasound monitoring ensured precise thrombin delivery while avoiding critical vascular structures, underscoring the technique’s safety and reproducibility. Our findings reinforce UGTI’s role in optimizing post-interventional vascular complication management.