Intramuscular hemangiomas on the masseter muscle and orbicularis oris muscle: a report of two cases.

Intramuscular hemangioma (IMH) is a rare vascular disease involving skeletal muscle, comprising only 0.8% of hemangiomas. About 10% to 15% of IMHs occur in the head and neck region, mostly involving the masseter muscle. IMH occurs mostly in childhood, but is often not found until unexpected enlargement, pain, or cosmetic asymmetry occurs in adulthood. Several non-surgical treatments including cryotherapy, sclerosant injection, and arterial ligature have been described, but complete surgical resection is the curative intervention. In this report, we present two rare cases of IMH. One IMH case in a 48-year-old male occurred in the masseter muscle feeding from the transverse facial artery. Embolization of the distal branch of the facial artery was first conducted, and then the buccal mass was removed surgically via the intraoral approach. A second IMH case in a 58-year-old female occurred in the orbicularis oris muscle feeding from the superior labial artery, and the mass was excised surgically without embolization.