Trigonocephaly vs. Birth Molding
Left picture: The diagnosis of this infant is a synostosis of the frontal suture, also descriptively called ´trigonocephaly´. Right picture: The diagnosis in this newborn is a birth molding in which the bones of the neurocranium slide one on top of the other and may mask a craniosynostosis during the neonatal period; later, there is a spontaneous correction of the deformity, and the autochthonous shape of the skull becomes visible. This course or natural history of birth molding can be illustrated by the pictures at the bottom with an x-ray at birth, and one 2 months later. In synostosis a birth molding is possible only to a limited degree.
On looking semi-obliquely from the side the vertex of the head seems to taper to a point in the infants, as well as in the child just born. Left picture: In the infant the deformity is restricted to the frontal region, if the patient is examined from all sides; striking is a keel-like deformity of the front, and a ridge of the midline. Right picture: The deformity is more generalized, and the head is tower-shaped in the posterior vertical region; all skull bones can be moved against each other.