Graft-Free ICA-to-ECA Transposition for a Giant Extracranial Carotid Artery Aneurysm in an Infant: A 13-Year Follow-Up Demonstrating Durable Patency and Growth Compatibility

INTRODUCTION: Extracranial carotid artery aneurysms (ECAAs) are exceedingly rare in children, with only a limited number of cases reported worldwide. Surgical reconstruction in infancy poses unique challenges owing to vascular fragility and the need for long-term growth compatibility. CASE PRESENTATION: We report the case of a 1-year-old boy with a large right ECAA who was treated with graft-free internal-to-external carotid artery (ICA-to-ECA) transposition. The aneurysm was completely resected, the proximal ICA was ligated, and the distal ICA was anastomosed adjacent to the ECA. Microsurgical reconstruction was performed under temporary clipping, with an occlusion time of 22 min. Postoperative angiography confirmed excellent flow through the transposed vessel. Serial imaging over a 13-year follow-up period demonstrated persistent patency without stenosis or proportional diameter growth of the reconstructed ICA, with no neurological complications or ischemic events. The anastomotic segment enlarged proportionally to the patient's cervical growth, indicating successful long-term biological integration. CONCLUSION: This case represents one of the longest documented follow-ups of pediatric ECAA reconstruction using native arterial tissues. Direct ICA-to-ECA transposition provides a durable, infection-free, and growth-adaptive solution superior to prosthetic or vein graft repair. This outcome underscores the central tenet of pediatric neurosurgery: surgical innovation must harmonize with a child's lifelong development.