C syndrome (also known as Opitz trigonocephaly syndrome) is a rare congenital disorder. Infants affected by this disorder have a malformated triangular shaped head due to premature union of the skull bones (trigonocephaly), a narrow pointed forehead, a flat broad nasal bridge with a short nose, vertical folds over the inner corners of the eyes, an abnormal palate that is deeply furrowed, abnormalities of the ear, crossed eyes (strabismus), joints that are bent or in a fixed position and loose skin.
The mortality rate during the first year of life is high. The disorder is autosomal recessive inherited. “C” is the first letter of the surname of the affected patients first described, hence the name C syndrome.