3D Nasolabial Morphology In Normal and Cleft Lip/Palate Subjects

Objectives: To measure differences in nasolabial morphology (1) among control subjects within different age groups; and (2) among patients with repaired unilateral and bilateral cleft lip and palate (CL/P) and control subjects.
Methods: Three-dimensional facial images of 184 control subjects (within age groups 5-7, n=36; 8-10, n=49; 11-13, n=53; 14-16, n=46 yrs.) and 42 patients with repaired CL/P (range 5-26 yrs.; mean age 11.9 yrs., S.D.=4.7) were captured using a 3dMDface System. Nasolabial landmarks were digitized on each subject’s ‘at rest’ image . Generalized Procrustes analysis was used to calculate the overall shape mean for the control subjects, and the distance from this mean was computed for each subject using ordinary Procrustes analysis. A “disfigurement score” based on the square root of the normalized Procrustes distance was taken as a measure of how far a subject was from the control mean. Comparisons were made of the nose, upper lip, and lower lip among the control groups; and among these regions between the controls and the patients. Pivotal bootstrap methods were used to test for significant group differences (p<0.001).
Results: There were no significant differences in mean disfigurement scores among the control groups. There were significant differences for the cleft patients. The bilaterals had higher scores for the nose and lower lip while the unilaterals had higher scores for the nose, upper lip, and lower lip; and the unilaterals had a greater range of scores.
Conclusions: The disfigurement of the entire nasolabial region was greater for the unilaterals compared with the bilaterals: The upper lip of the bilaterals was closer to normal. The unilaterals also had greater variation in disfigurement suggesting less uniformity of the surgical results following repair. This method can be used to objectively quantify the degree of nasolabial disfigurement in patients with CL/P compared to controls by means of a single score.