Sphenoid Bone Structure and Its Influence on the Cranium in Syndromic Versus Nonsyndromic Craniosynostosis

BACKGROUND Little is known about the detailed growth of the sphenoidal and temporal bones, even though they contribute significantly to the cranial base and cranial fossa skeletons. They also serve to connect the cranial vault with facial structure. This study details their morphologic development in isolated bicoronal synostosis and associated syndromes. METHODS Eighty-one CT scans were included (nonsyndromic bicoronal synostosis, n = 28; Apert syndrome associated with bicoronal synostosis, n = 19; Crouzon syndrome associated with bicoronal synostosis, n = 8; and controls, n = 26), and measured using Materialize software. RESULTS Sphenoidal and temporal bone volumes in nonsyndromic bicoronal synostosis are reduced 23% (P = 0.005) and 24%(P = 0.003) at 6 months of age, compared to controls. Apert and Crouzon syndrome patients developed similar reduced volumes. The greater wing of the sphenoid and pterygoid processes in nonsyndromic bicoronal synostosis are initially inferiorly rotated at 2 months of age, by 9.60° (P = 0.002) and 4.33° (P = 0.023), respectively. In Apert syndrome, these rotations were reduced by 4.82° (P = 0.003) and 12.60° (P