Determination of Facial Symmetry in Unilateral Cleft Lip and Palate Patients from Three-Dimensional Data: Technical Report and Assessment of Measurement Errors

Objective To assess measurement errors of a novel technique for the three-dimensional determination of the degree of facial symmetry in patients suffering from unilateral cleft lip and palate malformations. Design Technical report, reliability study. Setting Cleft Lip and Palate Center of the University of Erlangen-Nuremberg, Erlangen, Germany. Patients The three-dimensional facial surface data of five 10-year-old unilateral cleft lip and palate patients were subjected to the analysis. Distances, angles, surface areas, and volumes were assessed twice. Main Outcome Measures Calculations were made for method error, intraclass correlation coefficient, and repeatability of the measurements of distances, angles, surface areas, and volumes. Results The method errors were less than 1 mm for distances and less than 1.5° for angles. The intraclass correlation coefficients showed values greater than .90 for all parameters. The repeatability values were comparable for cleft and noncleft sides. Conclusion The small method errors, high intraclass correlation coefficients, and comparable repeatability values for cleft and noncleft sides reveal that the new technique is appropriate for clinical use.