Hypoplasia or absence of the depressor anguli oris muscle and congenital abnormalities, with special reference to the cardiofacial syndrome.

An asymmetrical crying facies due to hypoplasia or absence of the depressor anguli oris muscle (DAOM) was observed in 23 infants and children. The cases were divided into two groups. Group 1 consisted of 12 patients who had associated cardiac abnormalities. In group 2 were 11 patients who either had other non-cardiac abnormalities (6) or no other abnormalities (5). The associated cardiac anomalies recorded in the literature are reviewed and 2 infants in this series are reported with abnormalities not previously described. The results of chromosomal analysis have generally been found to be normal, although a patient in our series was found to have trisomy E (18). The incidence of hypoplasia of the DAOM in newborn infants in a maternity hospital hospital is assessed and was found to be lower than reported in other studies. It is concluded that a detailed and careful examination for congenital abnormalities should be carried out on every child with an asymmetrical crying facies.