Congenital hypoplasia of depressor anguli oris muscle (CHDAOM): an uncommon cause of asymmetric crying facies in childhood.

A 2-year-old developmentally normal girl presented to us with a history of deviation of angle of mouth to right only during crying, persisting from neonatal period. She was born at term by normal vaginal delivery to a primigravida mother with a birth weight of 2.2 kg and smooth perinatal transition. Parents noticed asymmetry of face from neonatal period visible only during crying, which disappeared when she was consoled, without any drooling, regurgitation of feeds or poor sucking. There is no history suggestive of any other neurological or systemic abnormality in index case or in family.Local examination revealed thinning of lower lip near left angle of mouth on palpation. There was no facial asymmetry while the child was calm (figure 1A), however, on crying there was deviation of the angle of mouth downwards and towards right side (figure 1B). There was no …