Embolotherapy with Onyx for Lower Limb Arteriovenous Malformation in a Child: Case Report

Objective: To explore the efficacy and safety of Onyx embolization in pediatric lower limb arteriovenous malformations (AVMs). Methods: The clinical data of a 3-year-old boy with AVMs were analyzed before and after Onyx embolization. Results: The child slowly developed a soft tissue mass with pain in the lateral left lateral thigh for approximately 2 years and had a history of local ulceration and bleeding 1 year ago. Two-dimensional ultrasound and color Doppler echocardiography showed an irregular soft tissue mass in the subcutaneous tissue of the right thigh, with unclear borders, rich blood flow signals, measurable arterial and venous blood flow. Lower extremity artery CT angiography (CTA) showed an irregular and abnormally enhanced vascular mass in the lateral left thigh with a lesion of about 3.9 cm * 2.4 cm * 1.0 cm, supplied by the deep femoral, popliteal and lateral knee arteries, and drained into the great saphenous vein. The child was confirmed with AVMs of the left lower limb. Under general anesthesia, the Marathon micro-catheter (Medtronic-ev3) was controlled to reach the feeding artery of the arteriovenous malformation of the left thigh. Onyx-18 was injected through the marathon microcatheter (Medtronic-ev3) at a speed of 0.10~0.15ml per minute to fully fill the focal chamber and then backward to fill the end of multiple branches of the feeding arteries. After Onyx embolization, the local swelling of the left lower limb lesion in the child resolved after 2 weeks. After 6 months of clinical follow-up, there was no local pain, ulcers, or bleeding. Conclusion: Onyx embolization is a safe and effective treatment for limb AVMs.