Craniosynostosis - Single Suture

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Craniosynostoses

Scaphocephaly

The most common type of synostosis; accounts for half of the incidences of synostosis each year.
There is synostosis of the sagittal suture – the skull is shaped like the narrow hull of a boat (the derivation of its name).
In accordance with Virchow's law, the interruption of brain growth is in perpendicular to the plane of the synostosis – thus the abnormal brain growth is in parallel to the synostosis. The skull elongates (in parallel to the synotic suture) – this results in an elongated, narrow skull.
The term dolichocephaly (elongated head) is either used synonymously scaphocephaly or as a broader catch-all for elongated head.

Brachycephaly

Results from bicoronal synostosis.
The skull cannot develop normally along the sagittal plane and we show, instead, that it manifests with a wide, short skull – again, in accordance with Virchow's law, the skull develops in parallel to the plane of the synostosis.
In unilateral coronal synostosis (as opposed to bilateral), also results in plagiocephaly because, as we can imagine, it results in a twisting/oblique appearance (but here of the frontal calvarium).

Trigonocephaly

Secondary to metopic synostosis, which results in a failure of frontal outward development.
It manifests with a pointed forehead… the eyebrows may appear "pinched."
To help link the name to the shape, we show that trigonocephaly results in a triangular shaped head, when viewed from above.

Lambdoid synostosis

Posterior plagiocephaly (a twisted skull) due to an inability of a side of the occiput to grow outward, thus there is an oblique oblique deformity of the posterior calvarial vault.