TY - JOUR
T1 - Quantification of facial asymmetry
T2 - A comparative study of landmark-based and surface-based registrations
AU - Verhoeven, Tim
AU - Xi, Tong
AU - Schreurs, Ruud
AU - Bergé, Stefaan
AU - Maal, Thomas
N1 - Publisher Copyright: © 2016 European Association for Cranio-Maxillo-Facial Surgery
PY - 2016
Y1 - 2016
N2 - Objective To compare the validity and reproducibility of four different methods for the quantification of soft tissue facial asymmetry. Material and methods Twenty 3D-photographs were randomly selected from the healthy control database. To assess the validity of the one landmark-based and three surface-based methods for measuring asymmetry, artificial facial asymmetry was created on two 3D photographs. The discrepancy between the artificial facial asymmetry and the asymmetry quantified by different methods was calculated. To evaluate the reproducibility of the methods, they were applied three times by two independent observers. The intraobserver and interobserver variations were calculated. Results The mean absolute differences between the measured asymmetry and the artificial asymmetry for the landmark-based method, forehead method, 5 mm method and 1 mm method were 1.4 mm, 0.3 mm, 0.09 mm and 0.06 mm respectively. The intraobserver and interobserver variations for the forehead, 5 mm and 1 mm methods were between 0.18 mm and 0.34 mm. Conclusion The surface-based methods were valid and highly reproducible in comparison to the landmark-based method for the quantification of soft tissue facial asymmetry. The 1 mm surface-based method can be implemented in a clinical and research setting to quantify facial asymmetry.
AB - Objective To compare the validity and reproducibility of four different methods for the quantification of soft tissue facial asymmetry. Material and methods Twenty 3D-photographs were randomly selected from the healthy control database. To assess the validity of the one landmark-based and three surface-based methods for measuring asymmetry, artificial facial asymmetry was created on two 3D photographs. The discrepancy between the artificial facial asymmetry and the asymmetry quantified by different methods was calculated. To evaluate the reproducibility of the methods, they were applied three times by two independent observers. The intraobserver and interobserver variations were calculated. Results The mean absolute differences between the measured asymmetry and the artificial asymmetry for the landmark-based method, forehead method, 5 mm method and 1 mm method were 1.4 mm, 0.3 mm, 0.09 mm and 0.06 mm respectively. The intraobserver and interobserver variations for the forehead, 5 mm and 1 mm methods were between 0.18 mm and 0.34 mm. Conclusion The surface-based methods were valid and highly reproducible in comparison to the landmark-based method for the quantification of soft tissue facial asymmetry. The 1 mm surface-based method can be implemented in a clinical and research setting to quantify facial asymmetry.
KW - 3D
KW - Asymmetry
KW - Maxillofacial surgery
KW - Registration
KW - Stereophotogrammetry
KW - Symmetry
UR - http://www.scopus.com/inward/record.url?scp=84994225779&partnerID=8YFLogxK
U2 - https://doi.org/10.1016/j.jcms.2016.07.017
DO - https://doi.org/10.1016/j.jcms.2016.07.017
M3 - Article
C2 - 27519663
SN - 1010-5182
VL - 44
SP - 1131
EP - 1136
JO - Journal of Cranio-Maxillofacial Surgery
JF - Journal of Cranio-Maxillofacial Surgery
IS - 9
ER -