Abstract
A 17-year-old girl with a congenital, painless right forehead swelling obstructing her visual field was diagnosed with sinus pericranii. Radiological imaging confirmed extracalvarial arteriovenous malformation with serpentine vessels and bony erosion. Endovascular surgery was chosen for management, highlighting the necessity of considering SP in differential diagnosis for scalp swellings. Despite its rarity, awareness of it is essential to prevent complications from injury, misdiagnosis, or invasive procedures.