Relationship of a Metopic Ridge and Anterior Cranial Volume Measured by a Noninvasive Laser Shape Digitizer

Cranial dysmorphology observed in patients with metopic craniosynostosis varies along a spectrum of severity including varying degrees of metopic ridging, bitemporal narrowing, and trigonocephaly. Management has been based upon the subjective clinical impression of presence and severity of trigonocephaly. Severity of cranial dysmorphology does not predict the occurrence or severity of associated abnormal neurodevelopment, as children with mild-to-moderate trigonocephaly may also experience developmental delays. The authors sought to determine the relationship between mild-to-moderate trigonocephaly and anterior cranial volume using a noninvasive laser shape digitizer (STARscanner) in patients with abnormal head shape.An IRB-approved retrospective review of a prospectively maintained database and medical records was performed. Two hundred three patients less than 1 year of age with abnormal head shape were categorized as having a metopic ridge with mild-to-moderate trigonocephaly, metopic ridge without trigonocephaly, or no ridge. Measurements of cranial volume, circumference, and symmetry were calculated by the STARscanner, which quantifies three-dimensional shape of the cranial surface. Measures were analyzed using a series of analyses of variance and post-hoc Tukey honest significant difference.The authors results showed ACV was significantly reduced in patients with mild-to-moderate trigonocephaly compared with those without metopic ridge (P = 0.009), and trended toward significance compared with those with a ridge but without trigonocephaly (P = 0.072). The ratio of anterior-to-posterior cranial volume was significantly reduced in those with mild-to-moderate trigonocephaly compared with those without metopic ridge (P = 0.036).In conclusion, patients with milder anterior cranial deformities demonstrated an association between a metopic ridge with mild-to-moderate trigonocephaly and reduced anterior cranial volume.