A case of arteriovenous malformation of the masseter muscle

Arteriovenous malformation (AVM) rarely occurs in the head and neck region. AVM of the masseter muscle is extremely rare. We report a case of AVM of the masseter muscle. The patient was a 54-year-old woman with pain of the left masseter muscle region for about 1 week. She had a movable mass in the left masseter region. On clenching, the mass became erect. Enhanced CT scanning showed a high density region in the masseter muscle. MRI T 1 imaging showed that the tumor was the same signal intensity as muscle. On MRI T 2 images, signal intensity of the mass was greater than that of fat. Color Doppler imaging showed high intensity color flow at the base of the mass. Under the diagnosis of an erectile hemangioma of the masseter muscle, the mass was resected surgically with an Nd: YAG laser via submandibular and preauricular approaches on May 17, 2000. Hemorrhage (20 grams) was controlled by ligation of the feeding artery. Histologically, the mass consisted mainly of cavernous hemangiomatous proliferation of veins with arterialisation and a few structurally deformed arteries. The pathological diagnosis was arteriovenous malformation. The postoperative course was without complications. As of 29 months after operation, there has been no sign of recurrence.