Benign osteonecrosis of the external ear canal.

Benign osteonecrosis (BON) of the external ear canal (EEC), also termed as focal or circumscribed necrotizing lesion, is an infrequent phenomenon with distinctive features and of an obscure origin. Five patients with BON of the EEC presented with aggressiveness and extension of varying degree including involvement of the middle ear. It seems that the disease might have a self limited course (two patients) though, at times, extensive measures including hyperbarric oxygen therapy (one patient) should be applied.