摘要
ASYMMETRIC crying facies （ACF） is characterized by facial asymmetry only when crying. It may present as an exclusive symptom, or be con-comitant with other congenital malformations nd even some fatal birth defects. Clinically, ACF is fea-tured by drooping of the intact corner of the mouth during crying, while the face appears symmetric at rest. The facial nerve function is symmetric, as determined by frowning, forehead wrinkling, eye closure, and nasolabial fold depth. When ACF alone is present, the cause is often compression of the mandibular branch of the facial nerve that is prob-ably due to birth trauma or abnormal fetal posture in utero. ACF with other congenital anomalies is usually caused by hypoplasia of the depressor anguli oris muscle （DAOM） on one side of the mouth.
