Measuring Symmetry in Children With Cleft Lip. Part 2: Quantification of Nasolabial Symmetry Before and After Cleft Lip Repair.

OBJECTIVE   The first part of this study validated an automated computer-based method of identifying the three-dimensional midfacial plane in children with unrepaired cleft lip. The purpose of this second part is to develop computer-based methods to quantify symmetry and to determine the correlation of these measures to clinical expectations. PARTICIPANTS   A total of 35 infants with unrepaired unilateral cleft lip and 14 infant controls. INTERVENTIONS   Six computer-based methods of quantifying symmetry were developed and applied to the three-dimensional images of infants with unilateral cleft lip before and after cleft lip repair and to those of controls. MAIN OUTCOME MEASURE   Symmetry scores for cleft type, changes with surgery, and individual subjects ranked according to cleft severity were assessed. RESULTS   Significant differences in symmetry scores were found between cleft types and found before and after surgery. Symmetry scores for infants with unilateral cleft lip approached those of controls after surgery, and there was a strong correlation with ranked cleft severity. CONCLUSIONS   Our computer-based three-dimensional analysis of nasolabial symmetry correlated with clinical expectations. Automated processing made measurement convenient. Use of these measures may help to objectively measure cleft severity and treatment outcome.