Comprehensive understanding of vascular anatomy for endovascular treatment of intractable oronasal bleeding.

Oronasal bleeding that continues despite oronasal packs or recurs after removal of the oronasal packs is referred to as intractable oronasal bleeding, which is refractory to conventional treatments. Severe craniofacial injury or tumor in the nasal or paranasal cavity may cause intractable oronasal bleeding. These intractable cases are subsequently treated with surgical ligation or endovascular embolization of the bleeding arteries. While endovascular embolization has several merits compared to surgical ligation, the procedure needs attention because severe complications such as visual disturbance or cerebral infarction can occur. Therefore, comprehensive understanding of the head and neck vascular anatomy is essential for a more effective and safer endovascular treatment of intractable oronasal bleeding.