The definitions of three‐dimensional landmarks on the human face: an interdisciplinary view

The analysis of shape is a key part of anatomical research and in the large majority of cases landmarks provide a standard starting point. However, while the technology of image capture has developed rapidly and in particular three-dimensional imaging is widely available, the definitions of anatomic...

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Detalles Bibliográficos
Autores: Katina, Stanislav, McNeil, Kathryn, Ayoub, Ashraf, Guilfoyle, Brendan, Khambay, Balvinder, Siebert, Paul, Sukno, Federico Mateo, Rojas, Mario A., Vittert, Liberty, Waddington, John L., Whelan, Paul F., Bowman, Adrian W.
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:10230/58850
Acceso en línea:http://hdl.handle.net/10230/58850
http://dx.doi.org/10.1111/joa.12407
Access Level:acceso abierto
Palabra clave:Curves
Landmarks
Reproducibility
Shape
Descripción
Sumario:The analysis of shape is a key part of anatomical research and in the large majority of cases landmarks provide a standard starting point. However, while the technology of image capture has developed rapidly and in particular three-dimensional imaging is widely available, the definitions of anatomical landmarks remain rooted in their two-dimensional origins. In the important case of the human face, standard definitions often require careful orientation of the subject. This paper considers the definitions of facial landmarks from an interdisciplinary perspective, including biological and clinical motivations, issues associated with imaging and subsequent analysis, and the mathematical definition of surface shape using differential geometry. This last perspective provides a route to definitions of landmarks based on surface curvature, often making use of ridge and valley curves, which is genuinely three-dimensional and is independent of orientation. Specific definitions based on curvature are proposed. These are evaluated, along with traditional definitions, in a study that uses a hierarchical (random effects) model to estimate the error variation that is present at several different levels within the image capture process. The estimates of variation at these different levels are of interest in their own right but, in addition, evidence is provided that variation is reduced at the observer level when the new landmark definitions are used.