Hemifacial Myohyperplasia

Hemifacial myohyperplasia is a rare developmental defect during embryogenesis characterized by unilateral hyperplasia of the facial musculature with no evidence of hyperplasia of bone or other organ systems. It clinically present with dimpling of the skin, ptosis, enophthalmos, narrow palpebral fissure, auricular displacement, smaller nasal vestibule, and nasal and chin deviation on the affected side. Facial paresis of the affected side and mild ipsilateral hypoplasia of the facial skeleton might be present.