ABSTRACT
The calvarium develops by intramembranous ossification. Islands of bone develop within the fibrous membrane, which later ossify. When two osteogenic fronts come in close proximity, a cranial suture develops (1). The sutures are essential to allow continuing expansion of the calvarium with age, especially in the first year of postnatal life when brain growth is rapid. The sutures close physiologically with age. The metopic is first to close in early perinatal life (3-9 months). Although normal fusion is thought to occur secondary to the loss of forces of separation created by the underlying brain, the precise cause of premature fusion is unknown.
