What is hemifacial microsomia primarily characterized by?

Hemifacial microsomia is primarily characterized by developmental issues that specifically affect the lower half of the face. This congenital condition often presents as an underdevelopment of structures on one side of the face, particularly affecting the mandible (lower jaw) and associated soft tissues, leading to facial asymmetry. The most common manifestations include anomalies of the ear, mandible, and oral cavity, which can result in functional challenges such as difficulties with eating, speaking, and breathing, as well as aesthetic concerns related to facial symmetry.

The diagnostic criteria for hemifacial microsomia emphasize its impact on the lower facial structures, distinguishing it from other conditions that might affect the upper face or limbs. Understanding this specific focus on the lower half of the face is critical for evaluating and managing the complexities associated with hemifacial microsomia.