Intramuscular Vascular Malformation of Masseter Muscle–A Rare Entity

Facial vascular malformations can cause dental emergencies that result in fatal or life-threatening and disfiguring situations. A knowledge of vascular malformation, its clinical presentation and its complications can prevent iatrogenically related accidents and minimize potential spontaneous crisis for the patient in the dental clinic. A vascular malformation (VM) is a morphogenetic abnormality of blood and/or lymphatic vessels with normal ultra-structural characteristics and endothelial hyperplasia. It results from a developmental arrest after the endothelial stage of embryologic vascular development contrary to hemangiomas, which appear to be a failure of differentiation at the endothelial stage. VM has a normal endothelial cell growth cycle that affects the veins, the capillaries and lymphatics and they do not involute. Intramuscular vascular malformations are uncommon tumors in the head and neck, although masseter muscle is the most common site, accounting for approximately 5% of all intramuscular vascular malformations in the head and neck region. Because of the rarity of these tumors, their deep location and unfamiliar presentation, inaccurate preoperative diagnosis and inappropriate treatment planning are common problems. The present report describes intramuscular arteriovenous malformation of masseter are presented highlighting the typical clinical presentation with MRI which should alert the dental physician to the possibility of such a lesion.