The association of DS with other ocular anomalies and congenital facial, skeletal, or neural abnormalities in 30-50% of patients further substantiates the hypothesis of disturbed embryogenesis. A teratogenic event during the second month of gestation seems to cause most ocular and extraocular abnormalities observed in combination with DS. DRS is present from birth, even if it is not recognized during infancy. An abnormal head posture and strabismus are often visible in old photographs taken in early childhood.