Neonatal death is frequent. Patients may have
mental retardation. On examination, the skull has a trilobed appearance with
high forehead, beaked nose, and depressed premaxillary region. Hydrocephalus
is common. Raised intracranial pressure is seen in approximately 45% of patients with
complex craniosynostoses. Other features involve the eyes (marked proptosis,
exophthalmos, corneal ulcerations) and the limbs (elbow ankylosis,
dysostosis multiplex, syndactyly of toes and fingers, restricted joint
mobility). Abnormal vertebral size has occasionally been reported.