Cranio-orbito-zygomatic measurements from standard CT scans in unoperated Crouzon and Apert infants: comparison with normal controls.

Cranio-orbito-zygomatic measurements taken from standard axial computed tomographic (CT) scans of unoperated patients with Crouzon syndrome (6 males, 14 females) and Apert syndrome (6 males, 10 females) under 1 year of age were compared to each other and to normal controls (40 males, 35 females). Fifteen cranio-orbito-zygomatic variables were measured and repeated. Means and standard deviations were computed for each sex, and means were pooled since they were not significantly different. Correlation coefficients for repeat measures (intra-observer error) of each variable showed good reproducibility. Only the lateral orbital wall angle differed between the syndromes (p = .034), suggesting that upper facial differences (as measured by these variables) do not manifest themselves at this young age. All measurements for both syndromes, except one, were outside the 95 percent confidence range for age-matched controls. Measurements taken from standard CT scans provide an objective comparison between specific syndromes and the normal population.