Maxillofacial vascular malformations (MFVMs) are formed due to an error of vascular morphogenesis. They generally grow in proportion to the growth of the affected child but may increase in size secondary to various triggering factors such as increased blood flow, arterial occlusion, and venous thrombosis. The development of an individual lesion, especially if it is high flow, may be stimulated by various factors. High flow in an existing MFVM can induce arteriovenous shunting, which, in turn, increases flow demand, cascading enlargement of the malformation. Increased understanding of these additional physiologic variants may help to define their clinical presentation and evolution and assist in designing therapeutic strategies.