CRANIOFACIAL SKELETAL MEASUREMENTS BASED ON COMPUTED-TOMOGRAPHY .1. ACCURACY AND REPRODUCIBILITY

Computed tomography (CT) is a useful modality for the management of cr aniofacial anomalies. A study was undertaken to assess whether CT meas urements of the upper craniofacial skeleton accurately represent the b ony region imaged. Measurements taken directly from five dry skulls (a pproximate ages: adults, over 18 years; child, 4 years; infant, 6 mont hs) were compared to those from axial CT scans of these skulls. Excell ent agreement was found between the direct (dry skull) and indirect (C T) measurements. The effect of head tilt on the accuracy of these meas urements was investigated. The error was within clinically acceptable limits (less than 5 percent) if the angle was no more than +/- 4-degre es from baseline (0-degrees). objective standardized information gaine d from CT should complement the subjective clinical data usually colle cted for the treatment of craniofacial deformities.